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/*
* Copyright 2004 The Closure Compiler Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.javascript.jscomp;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
import static com.google.javascript.jscomp.TypeCheck.MULTIPLE_VAR_DEF;
import static com.google.javascript.rhino.jstype.JSTypeNative.ARRAY_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.ARRAY_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.BOOLEAN_OBJECT_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.BOOLEAN_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.DATE_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.FUNCTION_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.GENERATOR_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.GLOBAL_THIS;
import static com.google.javascript.rhino.jstype.JSTypeNative.ITERABLE_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.ITERATOR_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.NULL_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.NUMBER_OBJECT_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.NUMBER_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.OBJECT_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.OBJECT_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.REGEXP_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.REGEXP_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.STRING_OBJECT_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.STRING_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.U2U_CONSTRUCTOR_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.UNKNOWN_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.VOID_TYPE;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Preconditions;
import com.google.common.base.Supplier;
import com.google.common.collect.HashBasedTable;
import com.google.common.collect.HashMultimap;
import com.google.common.collect.HashMultiset;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Iterables;
import com.google.common.collect.LinkedHashMultimap;
import com.google.common.collect.Lists;
import com.google.common.collect.Multimap;
import com.google.common.collect.Multiset;
import com.google.common.collect.Table;
import com.google.javascript.jscomp.CodingConvention.DelegateRelationship;
import com.google.javascript.jscomp.CodingConvention.ObjectLiteralCast;
import com.google.javascript.jscomp.CodingConvention.SubclassRelationship;
import com.google.javascript.jscomp.FunctionTypeBuilder.AstFunctionContents;
import com.google.javascript.jscomp.NodeTraversal.AbstractPostOrderCallback;
import com.google.javascript.jscomp.NodeTraversal.AbstractScopedCallback;
import com.google.javascript.jscomp.ProcessClosureProvidesAndRequires.ProvidedName;
import com.google.javascript.jscomp.modules.Export;
import com.google.javascript.jscomp.modules.Module;
import com.google.javascript.jscomp.modules.ModuleMap;
import com.google.javascript.jscomp.modules.ModuleMetadataMap;
import com.google.javascript.jscomp.modules.ModuleMetadataMap.ModuleMetadata;
import com.google.javascript.rhino.ErrorReporter;
import com.google.javascript.rhino.InputId;
import com.google.javascript.rhino.JSDocInfo;
import com.google.javascript.rhino.Node;
import com.google.javascript.rhino.NominalTypeBuilder;
import com.google.javascript.rhino.QualifiedName;
import com.google.javascript.rhino.StaticSymbolTable;
import com.google.javascript.rhino.Token;
import com.google.javascript.rhino.jstype.EnumType;
import com.google.javascript.rhino.jstype.FunctionParamBuilder;
import com.google.javascript.rhino.jstype.FunctionType;
import com.google.javascript.rhino.jstype.JSType;
import com.google.javascript.rhino.jstype.JSTypeNative;
import com.google.javascript.rhino.jstype.JSTypeRegistry;
import com.google.javascript.rhino.jstype.ObjectType;
import com.google.javascript.rhino.jstype.Property;
import com.google.javascript.rhino.jstype.StaticTypedScope;
import com.google.javascript.rhino.jstype.TemplateType;
import com.google.javascript.rhino.jstype.TemplateTypeMap;
import com.google.javascript.rhino.jstype.TemplateTypeReplacer;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.stream.Collectors;
import javax.annotation.Nullable;
/**
* Creates the symbol table of variables available in the current scope and their types.
*
* Scopes created by this class are very different from scopes created by the syntactic scope
* creator. These scopes have type information, and include some qualified names in addition to
* variables (like Class.staticMethod).
*
*
When building scope information, also declares relevant information about types in the type
* registry.
*/
final class TypedScopeCreator implements ScopeCreator, StaticSymbolTable {
/** A suffix for naming delegate proxies differently from their base. */
static final String DELEGATE_PROXY_SUFFIX = ObjectType.createDelegateSuffix("Proxy");
static final DiagnosticType MALFORMED_TYPEDEF =
DiagnosticType.warning(
"JSC_MALFORMED_TYPEDEF",
"Typedef for {0} does not have any type information");
static final DiagnosticType ENUM_INITIALIZER =
DiagnosticType.warning(
"JSC_ENUM_INITIALIZER_NOT_ENUM",
"enum initializer must be an object literal or an enum");
static final DiagnosticType INVALID_ENUM_KEY =
DiagnosticType.warning(
"JSC_INVALID_ENUM_KEY", "enum key must be a string or numeric literal");
static final DiagnosticType CTOR_INITIALIZER =
DiagnosticType.warning(
"JSC_CTOR_INITIALIZER_NOT_CTOR",
"Constructor {0} must be initialized at declaration");
static final DiagnosticType IFACE_INITIALIZER =
DiagnosticType.warning(
"JSC_IFACE_INITIALIZER_NOT_IFACE",
"Interface {0} must be initialized at declaration");
static final DiagnosticType CONSTRUCTOR_EXPECTED =
DiagnosticType.warning(
"JSC_REFLECT_CONSTRUCTOR_EXPECTED",
"Constructor expected as first argument");
static final DiagnosticType UNKNOWN_LENDS =
DiagnosticType.warning(
"JSC_UNKNOWN_LENDS",
"Variable {0} not declared before @lends annotation.");
static final DiagnosticType LENDS_ON_NON_OBJECT =
DiagnosticType.warning(
"JSC_LENDS_ON_NON_OBJECT",
"May only lend properties to object types. {0} has type {1}.");
static final DiagnosticType INCOMPATIBLE_ALIAS_ANNOTATION =
DiagnosticType.warning(
"JSC_INCOMPATIBLE_ALIAS_ANNOTATION",
"Annotation {0} on {1} incompatible with aliased type.");
static final DiagnosticType DYNAMIC_EXTENDS_WITHOUT_JSDOC =
DiagnosticType.warning(
"JSC_DYNAMIC_EXTENDS_WITHOUT_JSDOC",
"The right-hand side of an extends clause must be a qualified name, or else @extends must"
+ " be specified in JSDoc");
static final DiagnosticType CONFLICTING_GETTER_SETTER_TYPE =
DiagnosticType.warning(
"JSC_CONFLICTING_GETTER_SETTER_TYPE",
"The types of the getter and setter for property ''{0}'' do not match.\n"
+ "getter type is: {1}\n"
+ "setter type is: {2}");
static final DiagnosticGroup ALL_DIAGNOSTICS = new DiagnosticGroup(
DELEGATE_PROXY_SUFFIX,
MALFORMED_TYPEDEF,
ENUM_INITIALIZER,
CTOR_INITIALIZER,
IFACE_INITIALIZER,
CONSTRUCTOR_EXPECTED,
UNKNOWN_LENDS,
LENDS_ON_NON_OBJECT,
INCOMPATIBLE_ALIAS_ANNOTATION,
DYNAMIC_EXTENDS_WITHOUT_JSDOC);
private final AbstractCompiler compiler;
private final ErrorReporter typeParsingErrorReporter;
private final TypeValidator validator;
private final CodingConvention codingConvention;
private final JSTypeRegistry typeRegistry;
private final ModuleMap moduleMap;
private final ModuleMetadataMap metadataMap;
private final ModuleImportResolver moduleImportResolver;
private final boolean processClosurePrimitives;
private final List delegateProxyCtors = new ArrayList<>();
private final Map delegateCallingConventions = new HashMap<>();
private final Map memoized = new LinkedHashMap<>();
// Untyped scopes which contain unqualified names. Populated by FirstOrderFunctionAnalyzer to
// reserve names before the TypedScope is populated.
private final Map untypedScopes = new HashMap<>();
// Set of functions with non-empty returns, for passing to FunctionTypeBuilder.
private final Set functionsWithNonEmptyReturns = new HashSet<>();
// Includes both simple and qualified names.
private final Set escapedVarNames = new HashSet<>();
// Count of how many times each variable is assigned, for marking effectively final.
private final Multiset assignedVarNames = HashMultiset.create();
// For convenience
private final ObjectType unknownType;
// All names imported through goog.requireType. Resolve these after all scopes are created.
private final List weakImports = new ArrayList<>();
private final List deferredSetTypes = new ArrayList<>();
// Set of NAME, GETPROP, and STRING_KEY lvalues which should be treated as const declarations when
// assigned. Treat simple names in this list as if they were declared `const`. E.g. treat `exports
// = class {};` as `const exports = class {};`. Treat GETPROP and STRING_KEY nodes as if they were
// annotated @const.
private final Set undeclaredNamesForClosure = new HashSet<>();
// Maps EXPR_RESULT nodes from goog.provides to all implicitly provided names from the call
private final Multimap providedNamesFromCall = LinkedHashMultimap.create();
private class WeakModuleImport {
private final Node moduleLocalNode;
private final ScopedName scopedImport;
private final TypedScope localModuleScope;
WeakModuleImport(Node moduleLocalNode, ScopedName scopedImport, TypedScope localModuleScope) {
this.moduleLocalNode = moduleLocalNode;
this.scopedImport = scopedImport;
this.localModuleScope = localModuleScope;
}
void resolve() {
TypedScope resolvedScope = memoized.get(scopedImport.getScopeRoot());
// RequiredVar may be null if this is a bad import statement.
TypedVar requiredVar =
resolvedScope != null ? resolvedScope.getSlot(scopedImport.getName()) : null;
localModuleScope.declare(
moduleLocalNode.getString(),
moduleLocalNode,
requiredVar != null ? requiredVar.getType() : unknownType,
compiler.getInput(NodeUtil.getInputId(moduleLocalNode)),
requiredVar == null || requiredVar.isTypeInferred());
if (requiredVar != null && requiredVar.getNameNode().getTypedefTypeProp() != null) {
// Propagate the 'typedef type' from the module export to this variable. Otherwise
// NamedTypes pointing to the imported name fail to resolve.
JSType typedefType = requiredVar.getNameNode().getTypedefTypeProp();
moduleLocalNode.setTypedefTypeProp(typedefType);
typeRegistry.declareType(localModuleScope, moduleLocalNode.getString(), typedefType);
}
}
}
/**
* Defer attachment of types to nodes until all type names have been resolved. Then, we can
* resolve the type and attach it.
*/
private class DeferredSetType {
final Node node;
final JSType type;
DeferredSetType(Node node, JSType type) {
checkNotNull(node);
checkNotNull(type);
this.node = node;
this.type = type;
}
void resolve() {
node.setJSType(type.resolve(typeParsingErrorReporter));
}
}
/** Stores the type and qualified name for a destructuring rvalue. */
private static class RValueInfo {
@Nullable final JSType type;
@Nullable final QualifiedName qualifiedName;
RValueInfo(JSType type, QualifiedName qualifiedName) {
this.type = type;
this.qualifiedName = qualifiedName;
}
static RValueInfo empty() {
return new RValueInfo(null, null);
}
}
TypedScopeCreator(AbstractCompiler compiler) {
this(compiler, compiler.getCodingConvention());
}
TypedScopeCreator(AbstractCompiler compiler, CodingConvention codingConvention) {
this.compiler = compiler;
this.validator = compiler.getTypeValidator();
this.codingConvention = codingConvention;
this.typeRegistry = compiler.getTypeRegistry();
this.typeParsingErrorReporter = typeRegistry.getErrorReporter();
this.unknownType = typeRegistry.getNativeObjectType(UNKNOWN_TYPE);
this.metadataMap =
compiler.getModuleMetadataMap() != null
? compiler.getModuleMetadataMap()
: new ModuleMetadataMap(ImmutableMap.of(), ImmutableMap.of());
this.moduleMap = compiler.getModuleMap();
this.moduleImportResolver =
new ModuleImportResolver(this.moduleMap, getNodeToScopeMapper(), typeRegistry);
this.processClosurePrimitives = !this.metadataMap.getModulesByGoogNamespace().isEmpty();
}
private void report(JSError error) {
compiler.report(error);
}
@Override
public ImmutableList getReferences(TypedVar var) {
return ImmutableList.of(var);
}
@Override
public TypedScope getScope(TypedVar var) {
return var.scope;
}
@Override
public Iterable getAllSymbols() {
List vars = new ArrayList<>();
for (TypedScope s : memoized.values()) {
Iterables.addAll(vars, s.getAllSymbols());
}
return vars;
}
/**
* Returns a function mapping a scope root node to a {@link TypedScope}.
*
* This method mostly exists in lieu of an interface representing root node -> scope.
*/
public Function getNodeToScopeMapper() {
return memoized::get;
}
Collection getAllMemoizedScopes() {
// Return scopes in reverse order of creation so that IIFEs will
// come before the global scope.
return Lists.reverse(ImmutableList.copyOf(memoized.values()));
}
/**
* Removes all scopes with root nodes from a given script file.
*
* @param scriptName the name of the script file to remove nodes for.
*/
void removeScopesForScript(String scriptName) {
memoized.keySet().removeIf(n -> scriptName.equals(NodeUtil.getSourceName(n)));
}
/** Create a scope if it doesn't already exist, looking up in the map for the parent scope. */
TypedScope createScope(Node n) {
TypedScope s = memoized.get(n);
return s != null
? s
: createScope(n, createScope(NodeUtil.getEnclosingScopeRoot(n.getParent())));
}
/**
* Creates a scope with all types declared. Declares newly discovered types
* and type properties in the type registry.
*/
@Override
public TypedScope createScope(Node root, AbstractScope parent) {
checkArgument(parent == null || parent instanceof TypedScope);
TypedScope typedParent = (TypedScope) parent;
TypedScope scope = memoized.get(root);
if (scope != null) {
checkState(typedParent == scope.getParent());
} else {
scope = createScopeInternal(root, typedParent);
memoized.put(root, scope);
}
return scope;
}
private TypedScope createScopeInternal(Node root, TypedScope typedParent) {
// Constructing the global scope is very different than constructing
// inner scopes, because only global scopes can contain named classes that
// show up in the type registry.
TypedScope newScope = null;
AbstractScopeBuilder scopeBuilder = null;
Module module = ModuleImportResolver.getModuleFromScopeRoot(moduleMap, compiler, root);
if (typedParent == null) {
checkState(root.isRoot(), root);
Node externsRoot = root.getFirstChild();
Node jsRoot = root.getSecondChild();
checkState(externsRoot.isRoot(), externsRoot);
checkState(jsRoot.isRoot(), jsRoot);
JSType globalThis = typeRegistry.getNativeObjectType(JSTypeNative.GLOBAL_THIS);
// Mark the main root, the externs root, and the src root
// with the global this type.
root.setJSType(globalThis);
externsRoot.setJSType(globalThis);
jsRoot.setJSType(globalThis);
// Find all the classes in the global scope.
newScope = createInitialScope(root);
} else {
// Because JSTypeRegistry#getType looks up the scope in which a root of a qualified name is
// declared, pre-populate this TypedScope with all qualified name roots. This prevents
// type resolution from accidentally returning a type from an outer scope that is shadowed.
Scope untypedScope = untypedScopes.get(root);
Set reservedNames = new HashSet<>();
for (Var symbol : untypedScope.getAllSymbols()) {
reservedNames.add(symbol.getName());
}
if (module != null && module.metadata().isGoogModule()) {
// TypedScopeCreator treats default export assignments, like `exports = class {};`, as
// declarations. However, the untyped scope only contains an implicit slot for `exports`.
reservedNames.add("exports");
} else if (root.isFunction() && NodeUtil.isBundledGoogModuleCall(root.getParent())) {
// Pretend that 'exports' is declared in the block of goog.loadModule
// functions, not the function scope. See the above comment for why.
reservedNames.remove("exports");
}
newScope = new TypedScope(typedParent, root, reservedNames);
}
if (module != null) {
initializeModuleScope(root, module, newScope);
}
if (root.isFunction()) {
scopeBuilder = new FunctionScopeBuilder(newScope);
} else if (root.isClass()) {
scopeBuilder = new ClassScopeBuilder(newScope);
} else {
scopeBuilder = new NormalScopeBuilder(newScope, module);
}
scopeBuilder.build();
if (typedParent == null) {
List delegateProxies = new ArrayList<>();
for (FunctionType delegateProxyCtor : delegateProxyCtors) {
delegateProxies.add(
new NominalTypeBuilder(delegateProxyCtor, delegateProxyCtor.getInstanceType()));
}
codingConvention.defineDelegateProxyPrototypeProperties(
typeRegistry, delegateProxies, delegateCallingConventions);
}
if (module != null && module.metadata().isEs6Module()) {
// Declare an implicit variable representing the namespace of this module, then add a property
// for each exported name to that variable's type.
ObjectType namespace = typeRegistry.createAnonymousObjectType(null);
newScope.declare(
Export.NAMESPACE,
root, // Use the given MODULE_BODY as the 'declaration node' for lack of a better option.
namespace,
compiler.getInput(NodeUtil.getInputId(root)),
/* inferred= */ false);
moduleImportResolver.updateEsModuleNamespaceType(namespace, module, newScope);
}
return newScope;
}
/** Builds the beginning of a module-scope. This can be an ES module or a goog.module. */
private void initializeModuleScope(Node moduleBody, Module module, TypedScope moduleScope) {
if (module.metadata().isGoogModule()) {
declareExportsInModuleScope(module, moduleBody, moduleScope);
markGoogModuleExportsAsConst(moduleBody);
} else {
// For now, assume this is an ES module. In the future, it might be a CommonJS module.
checkState(module.metadata().isEs6Module(), "CommonJS module typechecking not supported yet");
Map unresolvedImports =
moduleImportResolver.declareEsModuleImports(
module, moduleScope, compiler.getInput(NodeUtil.getInputId(moduleBody)));
weakImports.addAll(
unresolvedImports.entrySet().stream()
.map(entry -> new WeakModuleImport(entry.getKey(), entry.getValue(), moduleScope))
.collect(Collectors.toList()));
}
}
/**
* Ensures that the name `exports` is declared in goog.module scope.
*
* If a goog.module explicitly assigns to exports, we want to treat that assignment inside the
* scope as if it were a declaration: `const exports = ...`. This method only handles cases where
* we want to treat exports as implicitly declared.
*/
private void declareExportsInModuleScope(
Module googModule, Node moduleBody, TypedScope moduleScope) {
if (!googModule.namespace().containsKey(Export.NAMESPACE)) {
// The goog.module never assigns `exports = ...`, so declare `exports` as an object literal.
moduleScope.declare(
"exports",
googModule.metadata().rootNode(),
typeRegistry.createAnonymousObjectType(null),
compiler.getInput(NodeUtil.getInputId(moduleBody)),
/* inferred= */ false);
}
}
/**
* Adds nodes representing goog.module exports to a list, to treat them as @const.
*
*
This method handles the following styles of exports:
*
*
* - {@code exports = class {}} adds the NAME node `exports`
*
- {@code exports = {Foo};} adds the NAME node `exports` and the STRING_KEY node `Foo`
*
- {@code exports.Foo = Foo;} adds the GETPROP node `exports.Foo`
*
*/
private void markGoogModuleExportsAsConst(Node moduleBody) {
// TODO(lharker): Use the source nodes from the Bindings once we no longer rewrite before
// typechecking. This is not feasible currently because a few places will rewrite exports = ...
for (Node statement : moduleBody.children()) {
if (!NodeUtil.isExprAssign(statement)) {
continue;
}
Node lhs = statement.getFirstFirstChild();
if (lhs.matchesQualifiedName("exports")) {
undeclaredNamesForClosure.add(lhs);
// If this is full of named exports, add all the string key nodes.
if (ClosureRewriteModule.isNamedExportsLiteral(lhs.getNext())) {
for (Node key : lhs.getNext().children()) {
undeclaredNamesForClosure.add(key);
}
}
} else if (lhs.isGetProp() && lhs.getFirstChild().matchesQualifiedName("exports")) {
undeclaredNamesForClosure.add(lhs);
}
}
}
/**
* Gathers all namespaces created by goog.provide and any definitions in code.
*
* This method does not actually declare anything in the scope. In order to accurately report
* redefinition warnings, wait to declare implicit names until the actual goog.provide call.
*
* @param root The global ROOT or a SCRIPT
*/
private void gatherAllProvides(Node root) {
if (!processClosurePrimitives) {
return;
}
Node externs = root.getFirstChild();
Node js = root.getSecondChild();
Map providedNames =
new ProcessClosureProvidesAndRequires(
compiler,
/* preprocessorSymbolTable= */ null,
CheckLevel.OFF,
/* preserveGoogProvidesAndRequires= */ true)
.collectProvidedNames(externs, js);
for (ProvidedName name : providedNames.values()) {
ModuleMetadata metadata = metadataMap.getModulesByGoogNamespace().get(name.getNamespace());
if (name.getCandidateDefinition() != null) {
// This name will be defined eventually. Don't worry about it.
Node firstDefinitionNode = name.getCandidateDefinition();
if (NodeUtil.isExprAssign(firstDefinitionNode)
&& firstDefinitionNode.getFirstFirstChild().isName()) {
// Treat assignments of provided names as declarations.
undeclaredNamesForClosure.add(firstDefinitionNode.getFirstFirstChild());
}
} else if (name.getFirstProvideCall() != null
&& NodeUtil.isExprCall(name.getFirstProvideCall())
&& (metadata == null || !metadata.isLegacyGoogModule())) {
// This name is implicitly created by a goog.provide call; declare it in the scope once
// reaching the provide call. The exception is legacy goog.modules, which are declared
// once leaving the module.
providedNamesFromCall.put(name.getFirstProvideCall(), name);
}
if (metadata != null && metadata.isGoogProvide()) {
typeRegistry.registerLegacyClosureModule(name.getNamespace());
}
}
}
/**
* Patches a given global scope by removing variables previously declared in a script and
* re-traversing a new version of that script.
*
* @param globalScope The global scope generated by {@code createScope}.
* @param scriptRoot The script that is modified.
*/
void patchGlobalScope(TypedScope globalScope, Node scriptRoot) {
// Preconditions: This is supposed to be called only on (named) SCRIPT nodes
// and a global typed scope should have been generated already.
checkState(scriptRoot.isScript());
checkNotNull(globalScope);
checkState(globalScope.isGlobal());
String scriptName = NodeUtil.getSourceName(scriptRoot);
checkNotNull(scriptName);
Predicate inScript = n -> scriptName.equals(NodeUtil.getSourceName(n));
escapedVarNames.removeIf(var -> inScript.test(var.getScopeRoot()));
assignedVarNames.removeIf(var -> inScript.test(var.getScopeRoot()));
functionsWithNonEmptyReturns.removeIf(inScript);
NodeTraversal.traverse(compiler, scriptRoot, new FirstOrderFunctionAnalyzer());
// TODO(bashir): Variable declaration is not the only side effect of last
// global scope generation but here we only wipe that part off.
// Remove all variables that were previously declared in this scripts.
// First find all vars to remove then remove them because of iterator.
List varsToRemove = new ArrayList<>();
for (TypedVar oldVar : globalScope.getVarIterable()) {
if (scriptName.equals(oldVar.getInputName())) {
varsToRemove.add(oldVar);
}
}
for (TypedVar var : varsToRemove) {
// By removing the type here, we're potentially invalidating any files that contain
// references to this type. Those files will need to be recompiled. Ideally, this
// was handled by the compiler (see b/29121507), but in the meantime users of incremental
// compilation will need to manage it themselves (e.g., by recompiling dependent files
// based on the dep graph).
String typeName = var.getName();
globalScope.undeclare(var);
globalScope.getTypeOfThis().toObjectType().removeProperty(typeName);
if (typeRegistry.getType(globalScope, typeName) != null) {
typeRegistry.removeType(globalScope, typeName);
}
}
// Now re-traverse the given script.
NormalScopeBuilder scopeBuilder = new NormalScopeBuilder(globalScope, /* module= */ null);
NodeTraversal.traverse(compiler, scriptRoot, scopeBuilder);
}
/**
* Create the outermost scope. This scope contains native binding such as {@code Object}, {@code
* Date}, etc.
*
* @param root The global ROOT node
*/
@VisibleForTesting
TypedScope createInitialScope(Node root) {
checkArgument(root.isRoot(), root);
// Gather global information used in typed scope creation. Use a memoized scope creator because
// scope-building takes a nontrivial amount of time.
MemoizedScopeCreator scopeCreator =
new MemoizedScopeCreator(new SyntacticScopeCreator(compiler));
new NodeTraversal(compiler, new FirstOrderFunctionAnalyzer(), scopeCreator)
.traverseRoots(root.getFirstChild(), root.getLastChild());
new NodeTraversal(
compiler,
new IdentifyEnumsAndTypedefsAsNonNullable(typeRegistry, codingConvention),
scopeCreator)
.traverse(root);
TypedScope s = TypedScope.createGlobalScope(root);
declareNativeFunctionType(s, ARRAY_FUNCTION_TYPE);
declareNativeFunctionType(s, BOOLEAN_OBJECT_FUNCTION_TYPE);
declareNativeFunctionType(s, DATE_FUNCTION_TYPE);
declareNativeFunctionType(s, FUNCTION_FUNCTION_TYPE);
declareNativeFunctionType(s, GENERATOR_FUNCTION_TYPE);
declareNativeFunctionType(s, ITERABLE_FUNCTION_TYPE);
declareNativeFunctionType(s, ITERATOR_FUNCTION_TYPE);
declareNativeFunctionType(s, NUMBER_OBJECT_FUNCTION_TYPE);
declareNativeFunctionType(s, OBJECT_FUNCTION_TYPE);
declareNativeFunctionType(s, REGEXP_FUNCTION_TYPE);
declareNativeFunctionType(s, STRING_OBJECT_FUNCTION_TYPE);
declareNativeValueType(s, "undefined", VOID_TYPE);
gatherAllProvides(root);
// Memoize the global scope so that module scope creation can access it. See
// AbstractScopeBuilder#shouldTraverse - modules are traversed early, as if they were always
// executed when control flow reaches the module body.
memoized.put(root, s);
return s;
}
private void declareNativeFunctionType(TypedScope scope, JSTypeNative tId) {
FunctionType t = typeRegistry.getNativeFunctionType(tId);
declareNativeType(scope, t.getInstanceType().getReferenceName(), t);
declareNativeType(
scope, t.getPrototype().getReferenceName(), t.getPrototype());
}
private void declareNativeValueType(TypedScope scope, String name,
JSTypeNative tId) {
declareNativeType(scope, name, typeRegistry.getNativeType(tId));
}
private static void declareNativeType(TypedScope scope, String name, JSType t) {
scope.declare(name, null, t, null, false);
}
/** Set the type for a node now, and enqueue it to be updated with a resolved type later. */
void setDeferredType(Node node, JSType type) {
// Other parts of this pass may read the not-yet-resolved type off the node.
// (like when we set the LHS of an assign with a typed RHS function.)
node.setJSType(type);
deferredSetTypes.add(new DeferredSetType(node, type));
}
void resolveTypes() {
// Declare goog.module type requires in scope.
for (WeakModuleImport weakImport : weakImports) {
weakImport.resolve();
}
// Resolve types and attach them to nodes.
for (DeferredSetType deferred : deferredSetTypes) {
deferred.resolve();
}
// Resolve types and attach them to scope slots.
for (TypedScope scope : getAllMemoizedScopes()) {
for (TypedVar var : scope.getVarIterable()) {
var.resolveType(typeParsingErrorReporter);
}
scope.validateCompletelyBuilt();
}
// Tell the type registry that any remaining types are unknown.
typeRegistry.resolveTypes();
}
/** Adds all enums and typedefs to the registry's list of non-nullable types. */
private static class IdentifyEnumsAndTypedefsAsNonNullable extends AbstractPostOrderCallback {
private final JSTypeRegistry registry;
private final CodingConvention codingConvention;
IdentifyEnumsAndTypedefsAsNonNullable(
JSTypeRegistry registry, CodingConvention codingConvention) {
this.registry = registry;
this.codingConvention = codingConvention;
}
@Override
public void visit(NodeTraversal t, Node node, Node parent) {
switch (node.getToken()) {
case LET:
case CONST:
case VAR:
for (Node child = node.getFirstChild(); child != null; child = child.getNext()) {
// TODO(b/116853368): make this work for destructuring aliases as well.
identifyEnumOrTypedefDeclaration(
t, child, child.getFirstChild(), NodeUtil.getBestJSDocInfo(child));
}
break;
case EXPR_RESULT:
Node firstChild = node.getFirstChild();
if (firstChild.isAssign()) {
Node assign = firstChild;
identifyEnumOrTypedefDeclaration(
t, assign.getFirstChild(), assign.getSecondChild(), assign.getJSDocInfo());
} else if (firstChild.isGetProp()) {
identifyEnumOrTypedefDeclaration(
t, firstChild, /* rvalue= */ null, firstChild.getJSDocInfo());
}
break;
default:
break;
}
}
private void identifyEnumOrTypedefDeclaration(
NodeTraversal t, Node nameNode, @Nullable Node rvalue, JSDocInfo info) {
if (!nameNode.isQualifiedName()) {
return;
}
if (info != null && info.hasEnumParameterType()) {
registry.identifyNonNullableName(t.getScope(), nameNode.getQualifiedName());
} else if (info != null && info.hasTypedefType()) {
registry.identifyNonNullableName(t.getScope(), nameNode.getQualifiedName());
} else if (rvalue != null
&& rvalue.isQualifiedName()
&& registry.isNonNullableName(t.getScope(), rvalue.getQualifiedName())
&& NodeUtil.isConstantDeclaration(codingConvention, info, nameNode)) {
registry.identifyNonNullableName(t.getScope(), nameNode.getQualifiedName());
}
}
}
private JSType getNativeType(JSTypeNative nativeType) {
return typeRegistry.getNativeType(nativeType);
}
private abstract class AbstractScopeBuilder implements NodeTraversal.Callback {
/** The scope that we're building. */
final TypedScope currentScope;
/** The current hoist scope. */
final TypedScope currentHoistScope;
/** The current source file that we're in. */
private String sourceName = null;
/** The InputId of the current node. */
private InputId inputId;
/** The Module object for this scope, if any. */
private Module module;
/**
* Some actions need to be deferred, such as analyzing object literals with
* lends annotations, or resolving type-less stubs. These actions are added
* to this map, keyed by the node that should be waited for before running.
*/
final Multimap deferredActions = HashMultimap.create();
AbstractScopeBuilder(TypedScope scope, Module module) {
this.currentScope = scope;
this.currentHoistScope = scope.getClosestHoistScope();
this.module = module;
}
/** Returns the current compiler input. */
CompilerInput getCompilerInput() {
return compiler.getInput(inputId);
}
/** Traverse the scope root and build it. */
void build() {
new NodeTraversal(compiler, this, ScopeCreator.ASSERT_NO_SCOPES_CREATED)
.traverseAtScope(currentScope);
finishDeclaringGoogModule();
}
private void finishDeclaringGoogModule() {
if (module == null || !module.metadata().isGoogModule()) {
return;
}
TypedVar exportsVar = checkNotNull(currentScope.getSlot("exports"));
if (module.metadata().isLegacyGoogModule()) {
typeRegistry.registerLegacyClosureModule(module.closureNamespace());
QualifiedName moduleNamespace = QualifiedName.of(module.closureNamespace());
currentScope
.getGlobalScope()
.declare(
moduleNamespace.join(),
exportsVar.getNameNode(),
exportsVar.getType(),
exportsVar.getInput(),
exportsVar.isTypeInferred());
if (!moduleNamespace.isSimple()) {
JSType parentType =
currentScope.getGlobalScope().lookupQualifiedName(moduleNamespace.getOwner());
if (parentType != null && parentType.toMaybeObjectType() != null) {
parentType
.toMaybeObjectType()
.defineDeclaredProperty(
moduleNamespace.getComponent(), exportsVar.getType(), exportsVar.getNameNode());
}
}
declareAliasTypeIfRvalueIsAliasable(
module.closureNamespace(),
exportsVar.getNameNode(), // Pretend that 'exports = '... is the lvalue node.
QualifiedName.of("exports"),
exportsVar.getType(),
currentScope,
currentScope.getGlobalScope());
} else {
typeRegistry.registerClosureModule(
module.closureNamespace(), exportsVar.getNameNode(), exportsVar.getType());
}
// Store the type of the namespace on the AST for the convenience of later passes that want
// to access it.
Node rootNode = module.metadata().rootNode();
if (rootNode.isScript()) {
Node moduleBody = rootNode.getFirstChild();
moduleBody.setJSType(exportsVar.getType());
} else {
// For goog.loadModule, give the `exports` parameter the correct type.
Node paramList = NodeUtil.getFunctionParameters(rootNode.getSecondChild());
paramList.getOnlyChild().setJSType(exportsVar.getType());
}
}
@Override
public final boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
inputId = t.getInputId();
if (n.isFunction() || n.isScript() || (parent == null && inputId != null)) {
checkNotNull(inputId);
sourceName = NodeUtil.getSourceName(n);
}
if (parent == null || inCurrentScope(t)) {
visitPreorder(t, n, parent);
return true;
} else if (n.isModuleBody()) {
// Visit modules pre-order. While this doesn't exactly match execution semantics, it
// does match how the compiler rewrites modules into the global scope.
createScope(n, currentScope);
} else if (NodeUtil.isBundledGoogModuleScopeRoot(n)) {
TypedScope functionScope = createScope(parent, currentScope);
createScope(n, functionScope);
}
return false;
}
private boolean inCurrentScope(NodeTraversal t) {
Node traversalScopeRoot = t.getScopeRoot();
// NOTE: we need special handling for SCRIPT nodes, since Compiler.replaceScript causes a
// traversal rooted at a SCRIPT but with the global scope whose root node is the ROOT.
if (traversalScopeRoot.isScript()) {
return currentScope.isGlobal();
}
// Otherwise we're in the current scope as long as the root nodes match up.
return traversalScopeRoot == currentScope.getRootNode();
}
@Override
public final void visit(NodeTraversal t, Node n, Node parent) {
inputId = t.getInputId();
if (parent != null) {
attachLiteralTypes(n);
visitPostorder(t, n, parent);
if (deferredActions.containsKey(n)) { // streams are expensive, only make if needed
deferredActions.removeAll(n).stream().forEach(Runnable::run);
}
} else if (!deferredActions.isEmpty()) {
// Run *all* remaining deferred actions, in case any were missed.
deferredActions.values().stream().forEach(Runnable::run);
}
}
/** Called by shouldTraverse on nodes after ensuring the inputId is set. */
void visitPreorder(NodeTraversal t, Node n, Node parent) {}
/** Called by visit on nodes after updating the inputId. */
void visitPostorder(NodeTraversal t, Node n, Node parent) {}
void attachLiteralTypes(Node n) {
switch (n.getToken()) {
case NULL:
n.setJSType(getNativeType(NULL_TYPE));
break;
case VOID:
n.setJSType(getNativeType(VOID_TYPE));
break;
case STRING:
case TEMPLATELIT_STRING:
n.setJSType(getNativeType(STRING_TYPE));
break;
case NUMBER:
n.setJSType(getNativeType(NUMBER_TYPE));
break;
case TRUE:
case FALSE:
n.setJSType(getNativeType(BOOLEAN_TYPE));
break;
case REGEXP:
n.setJSType(getNativeType(REGEXP_TYPE));
break;
case OBJECTLIT:
JSDocInfo info = n.getJSDocInfo();
if (info != null && info.hasLendsName()) {
// Defer analyzing object literals with a @lends annotation until we
// reach the root of the statement they're defined in.
//
// This ensures that if there are any @lends annotations on the object
// literals, the type on the @lends annotation resolves correctly.
//
// For more information, see http://blickly.github.io/closure-compiler-issues/#314
deferredActions.put(NodeUtil.getEnclosingStatement(n), () -> defineObjectLiteral(n));
} else {
defineObjectLiteral(n);
}
break;
case CLASS:
// NOTE(sdh): We can't handle function nodes here because they need special behavior to
// deal with hoisting. But since classes aren't hoisted, and may need to be handled in
// such places as default method initializers (i.e. in a FunctionScope) or class extends
// clauses (technically part of the ClassScope, but visited instead by the NormalScope),
// they can be handled consistently in all scopes.
defineClassLiteral(n);
break;
// NOTE(johnlenz): If we ever support Array tuples,
// we will need to handle them here as we do object literals
// above.
case ARRAYLIT:
n.setJSType(getNativeType(ARRAY_TYPE));
break;
default:
break;
}
}
private void defineObjectLiteral(Node objectLit) {
// Handle the @lends annotation.
JSType type = null;
JSDocInfo info = objectLit.getJSDocInfo();
if (info != null && info.hasLendsName()) {
String lendsName = info.getLendsName().getRoot().getString();
TypedVar lendsVar = currentScope.getVar(lendsName);
if (lendsVar == null) {
report(JSError.make(objectLit, UNKNOWN_LENDS, lendsName));
} else {
type = lendsVar.getType();
if (type == null) {
type = unknownType;
}
if (!type.isSubtypeOf(typeRegistry.getNativeType(OBJECT_TYPE))) {
report(JSError.make(
objectLit, LENDS_ON_NON_OBJECT, lendsName, type.toString()));
type = null;
} else {
objectLit.setJSType(type);
}
}
}
info = NodeUtil.getBestJSDocInfo(objectLit);
boolean createEnumType = info != null && info.hasEnumParameterType();
if (createEnumType) {
Node lValue = NodeUtil.getBestLValue(objectLit);
String lValueName = NodeUtil.getBestLValueName(lValue);
type = createEnumTypeFromNodes(objectLit, lValueName, lValue, info);
}
if (type == null) {
type = typeRegistry.createAnonymousObjectType(info);
}
setDeferredType(objectLit, type);
// If this is an enum, the properties were already taken care of above.
processObjectLitProperties(
objectLit, ObjectType.cast(objectLit.getJSType()), !createEnumType);
}
/**
* Process an object literal and all the types on it.
* @param objLit The OBJECTLIT node.
* @param objLitType The type of the OBJECTLIT node. This might be a named
* type, because of the lends annotation.
* @param declareOnOwner If true, declare properties on the objLitType as
* well. If false, the caller should take care of this.
*/
void processObjectLitProperties(
Node objLit, ObjectType objLitType,
boolean declareOnOwner) {
for (Node keyNode = objLit.getFirstChild(); keyNode != null; keyNode = keyNode.getNext()) {
if (keyNode.isComputedProp() || keyNode.isSpread()) {
// Don't try defining computed or spread properties on an object. Note that for spread
// type inference will try to determine the properties and types. We cannot do it here as
// we don't have all the type information of the spread object.
continue;
}
Node value = keyNode.getFirstChild();
String memberName = NodeUtil.getObjectLitKeyName(keyNode);
JSDocInfo info = keyNode.getJSDocInfo();
JSType valueType = getDeclaredType(info, keyNode, value, null);
JSType keyType =
objLitType.isEnumType()
? objLitType.toMaybeEnumType().getElementsType()
: TypeCheck.getObjectLitKeyTypeFromValueType(keyNode, valueType);
// Try to declare this property in the current scope if it
// has an authoritative name.
String qualifiedName = NodeUtil.getBestLValueName(keyNode);
if (qualifiedName != null) {
new SlotDefiner()
.forDeclarationNode(keyNode)
.forVariableName(qualifiedName)
.inScope(getLValueRootScope(keyNode))
.withType(keyType)
.allowLaterTypeInference(keyType == null)
.defineSlot();
} else if (keyType != null) {
setDeferredType(keyNode, keyType);
}
if (keyType != null && objLitType != null && declareOnOwner) {
// Declare this property on its object literal.
objLitType.defineDeclaredProperty(memberName, keyType, keyNode);
}
}
}
/**
* Returns the type specified in a JSDoc annotation near a GETPROP, NAME, member function, or
* object literal key.
*
* Extracts type information from the {@code @type} tag.
*/
private JSType getDeclaredTypeInAnnotation(Node node, JSDocInfo info) {
checkArgument(info.hasType());
ImmutableList ownerTypeKeys = ImmutableList.of();
Node ownerNode = NodeUtil.getBestLValueOwner(node);
String ownerName = NodeUtil.getBestLValueName(ownerNode);
ObjectType ownerType = null;
if (ownerName != null) {
TypedVar ownerVar = currentScope.getVar(ownerName);
if (ownerVar != null) {
ownerType = getPrototypeOwnerType(ObjectType.cast(ownerVar.getType()));
if (ownerType != null) {
ownerTypeKeys = ownerType.getTemplateTypeMap().getTemplateKeys();
}
}
}
StaticTypedScope templateScope =
!ownerTypeKeys.isEmpty()
? typeRegistry.createScopeWithTemplates(currentScope, ownerTypeKeys)
: currentScope;
return info.getType().evaluate(templateScope, typeRegistry);
}
/**
* Asserts that it's OK to define this node's name.
* The node should have a source name and be of the specified type.
*/
void assertDefinitionNode(Node n, Token type) {
checkState(sourceName != null);
checkState(n.getToken() == type, n);
}
/**
* Defines a catch parameter.
*/
void defineCatch(Node n) {
assertDefinitionNode(n, Token.CATCH);
// Though almost certainly a terrible idea, it is possible to do destructuring in
// the catch declaration.
// e.g. `} catch ({message, errno}) {`
for (Node catchName : NodeUtil.findLhsNodesInNode(n)) {
JSType type = getDeclaredType(catchName.getJSDocInfo(), catchName, null, null);
new SlotDefiner()
.forDeclarationNode(catchName)
.forVariableName(catchName.getString())
.inScope(currentScope)
.withType(type)
.allowLaterTypeInference(type == null)
.defineSlot();
}
}
/** Defines an assignment to a name as if it were an actual declaration. */
void defineAssignAsIfDeclaration(Node assignment) {
JSDocInfo info = assignment.getJSDocInfo();
Node name = assignment.getFirstChild();
checkArgument(name.isName(), name);
Node rvalue = assignment.getSecondChild();
defineName(name, rvalue, currentScope, info);
}
/** Defines a variable declared with `var`, `let`, or `const`. */
void defineVars(Node n) {
checkState(sourceName != null);
checkState(NodeUtil.isNameDeclaration(n));
JSDocInfo info = n.getJSDocInfo();
// `var` declarations are hoisted, but `let` and `const` are not.
TypedScope scope = n.isVar() ? currentHoistScope : currentScope;
if (n.hasMoreThanOneChild() && info != null) {
report(JSError.make(n, MULTIPLE_VAR_DEF));
}
for (Node child : n.children()) {
defineVarChild(info, child, scope);
}
if (n.hasOneChild() && isValidTypedefDeclaration(n.getOnlyChild(), n.getJSDocInfo())) {
declareTypedefType(n.getOnlyChild(), n.getJSDocInfo());
}
}
/** Defines a variable declared with `var`, `let`, or `const`. */
void defineVarChild(JSDocInfo declarationInfo, Node child, TypedScope scope) {
if (child.isName()) {
if (declarationInfo == null) {
declarationInfo = child.getJSDocInfo();
// TODO(bradfordcsmith): Report an error if both the declaration node and the name itself
// have JSDoc.
}
defineName(child, child.getFirstChild(), scope, declarationInfo);
} else {
checkState(child.isDestructuringLhs(), child);
Node pattern = child.getFirstChild();
Node value = child.getSecondChild();
if (ModuleImportResolver.isGoogModuleDependencyCall(value)) {
// Define destructuring names here, since goog.require destructuring patterns can only
// have one level and require some special handling.
ScopedName defaultImport = moduleImportResolver.getClosureNamespaceTypeFromCall(value);
for (Node key : pattern.children()) {
defineModuleImport(key.getFirstChild(), defaultImport, key.getString());
}
return;
}
defineDestructuringPatternInVarDeclaration(
pattern,
scope,
() ->
// Note that value will be null if we are in an enhanced for loop
// for (const {x, y} of data) {
value != null
? new RValueInfo(
getDeclaredRValueType(/* lValue= */ null, value),
value.getQualifiedNameObject())
: new RValueInfo(unknownType, /* qualifiedName= */ null));
}
}
/**
* Returns information about the qualified name and type of the target, if it exists.
*
* Never returns null, but will return an RValueInfo with null `type` and `qualifiedName`
* slots.
*/
private RValueInfo inferTypeForDestructuredTarget(
DestructuredTarget target, Supplier patternTypeSupplier) {
// Currently we only do type inference for string key nodes in object patterns here, to
// handle aliasing types. e.g
// const {Foo} = ns;
// TypeInference takes care of the rest.
// Note that although DestructuredTarget includes logic for inferring types, we don't use
// it here because we only do some very limited type inference during TypedScopeCreation,
// and only return a non-null type here if we are accessing a declared property on a known
// type.
if (!target.hasStringKey() || target.hasDefaultValue()) {
return RValueInfo.empty();
}
RValueInfo rvalue = patternTypeSupplier.get();
JSType patternType = rvalue.type;
String propertyName = target.getStringKey().getString();
QualifiedName qname =
rvalue.qualifiedName != null ? rvalue.qualifiedName.getprop(propertyName) : null;
if (patternType == null || patternType.isUnknownType()) {
return new RValueInfo(null, qname);
}
if (patternType.hasProperty(propertyName)) {
JSType type = patternType.findPropertyType(propertyName);
return new RValueInfo(type, qname);
}
return new RValueInfo(null, qname);
}
void defineDestructuringPatternInVarDeclaration(
Node pattern, TypedScope scope, Supplier patternTypeSupplier) {
for (DestructuredTarget target :
DestructuredTarget.createAllNonEmptyTargetsInPattern(
typeRegistry, () -> patternTypeSupplier.get().type, pattern)) {
Supplier typeSupplier =
() -> inferTypeForDestructuredTarget(target, patternTypeSupplier);
if (target.getNode().isDestructuringPattern()) {
defineDestructuringPatternInVarDeclaration(target.getNode(), scope, typeSupplier);
} else {
Node name = target.getNode();
checkState(name.isName(), "This method is only for declaring variables: %s", name);
// variable's type
JSType type =
getDeclaredType(name.getJSDocInfo(), name, /* rValue= */ null, typeSupplier);
if (type == null) {
// The variable's type will be inferred.
type = name.isFromExterns() ? unknownType : null;
}
new SlotDefiner()
.forDeclarationNode(name)
.forVariableName(name.getString())
.inScope(scope)
.withType(type)
.allowLaterTypeInference(type == null)
.defineSlot();
}
}
}
/**
* Defines a class literal. Handles any of the following cases:
*
* - Class declarations:
class Foo { ... }
* - Class assignments:
foo.Bar = class { ... }
* - Bleeding names:
foo.Bar = class Baz { ... }
* - Properties:
{foo: class { ... }}
* - Callbacks:
foo(class { ... })
*
*/
void defineClassLiteral(Node n) {
assertDefinitionNode(n, Token.CLASS);
// Determine the name and JSDocInfo and l-value for the class.
// Any of these may be null.
Node lValue = NodeUtil.getBestLValue(n);
JSDocInfo info = NodeUtil.getBestJSDocInfo(n);
String className = NodeUtil.getBestLValueName(lValue);
// Create the type and assign it on the CLASS node.
FunctionType classType = createClassTypeFromNodes(n, className, info, lValue);
setDeferredType(n, classType);
// Declare this symbol in the current scope iff it's a class
// declaration. Otherwise, the declaration will happen in other
// code paths.
if (NodeUtil.isClassDeclaration(n)) {
checkNotNull(className);
new SlotDefiner()
.forDeclarationNode(n.getFirstChild())
.forVariableName(className)
.inScope(currentScope)
.withType(classType)
.allowLaterTypeInference(classType == null)
.defineSlot();
}
}
/**
* Defines a function literal.
*/
void defineFunctionLiteral(Node n) {
assertDefinitionNode(n, Token.FUNCTION);
// Determine the name and JSDocInfo and l-value for the function.
// Any of these may be null.
Node lValue = NodeUtil.getBestLValue(n);
JSDocInfo info = NodeUtil.getBestJSDocInfo(n);
String functionName = NodeUtil.getBestLValueName(lValue);
FunctionType functionType = createFunctionTypeFromNodes(n, functionName, info, lValue);
// Assigning the function type to the function node
setDeferredType(n, functionType);
// Declare this symbol in the current scope iff it's a function
// declaration. Otherwise, the declaration will happen in other
// code paths.
if (NodeUtil.isFunctionDeclaration(n)) {
new SlotDefiner()
.forDeclarationNode(n.getFirstChild())
.forVariableName(functionName)
.inScope(currentScope)
.withType(functionType)
.allowLaterTypeInference(functionType == null)
.defineSlot();
}
}
/**
* Defines a variable based on the {@link Token#NAME} node passed.
*
* @param name The {@link Token#NAME} node.
* @param value Optionally, the value assigned to the name node.
* @param scope
* @param info the {@link JSDocInfo} information relating to this {@code name} node.
*/
private void defineName(Node name, Node value, TypedScope scope, JSDocInfo info) {
if (ModuleImportResolver.isGoogModuleDependencyCall(value)) {
defineModuleImport(name, moduleImportResolver.getClosureNamespaceTypeFromCall(value), null);
return;
}
JSType type = getDeclaredType(info, name, value, /* declaredRValueTypeSupplier= */ null);
if (type == null) {
// The variable's type will be inferred.
type = name.isFromExterns() ? unknownType : null;
}
new SlotDefiner()
.forDeclarationNode(name)
.forVariableName(name.getString())
.inScope(scope)
.withType(type)
.allowLaterTypeInference(type == null)
.defineSlot();
}
private void defineModuleImport(
Node localNameNode, @Nullable ScopedName exportedName, String optionalProperty) {
if (exportedName == null) {
// We could not find the module defining this import. Just declare the name as unknown.
new SlotDefiner()
.forDeclarationNode(localNameNode)
.forVariableName(localNameNode.getString())
.inScope(currentScope)
.withType(unknownType)
.allowLaterTypeInference(true)
.defineSlot();
return;
}
// Check if this is a goog dependency loading call. If so, find its type.
if (optionalProperty != null) {
exportedName =
ScopedName.of(
exportedName.getName() + "." + optionalProperty, exportedName.getScopeRoot());
}
// Try getting the actual scope. The scope will be null in the following cases:
// - Someone has required a module that does not exist at all.
// - Someone has requireType'd or forwardDeclare'd a module that exists, but does not have
// an associated scope yet.
TypedScope exportScope =
exportedName.getScopeRoot() != null ? memoized.get(exportedName.getScopeRoot()) : null;
// The scope is null for modules that were not visited yet.
if (exportScope != null) {
JSType type = exportScope.lookupQualifiedName(QualifiedName.of(exportedName.getName()));
// The type is null if either the name is inferred or this is an early ref.
if (type != null) {
declareAliasTypeIfRvalueIsAliasable(
localNameNode, QualifiedName.of(exportedName.getName()), type, exportScope);
new SlotDefiner()
.forDeclarationNode(localNameNode)
.forVariableName(localNameNode.getString())
.inScope(currentScope)
.withType(type)
.allowLaterTypeInference(type == null)
.defineSlot();
return;
}
}
// Defer defining this name until after we have visited the entire AST.
weakImports.add(new WeakModuleImport(localNameNode, exportedName, currentScope));
}
/**
* If a variable is assigned a function literal in the global scope,
* make that a declared type (even if there's no doc info).
* There's only one exception to this rule:
* if the return type is inferred, and we're in a local
* scope, we should assume the whole function is inferred.
*/
private boolean shouldUseFunctionLiteralType(
FunctionType type, JSDocInfo info, Node lValue) {
if (info != null) {
return true;
}
if (lValue != null && NodeUtil.mayBeObjectLitKey(lValue)) {
return false;
}
// TODO(johnlenz): consider unifying global and local behavior
return isLValueRootedInGlobalScope(lValue) || !type.isReturnTypeInferred();
}
/**
* Creates a new class type from the given class literal. This function does not need to worry
* about stubs and aliases because they are handled by createFunctionTypeFromNodes instead.
*/
private FunctionType createClassTypeFromNodes(
Node clazz, @Nullable String name, @Nullable JSDocInfo info, @Nullable Node lvalueNode) {
checkArgument(clazz.isClass(), clazz);
FunctionTypeBuilder builder =
new FunctionTypeBuilder(name, compiler, clazz, currentScope)
.usingClassSyntax()
.setContents(new AstFunctionContents(clazz))
.setDeclarationScope(
lvalueNode != null ? getLValueRootScope(lvalueNode) : currentScope)
.inferKind(info)
.inferTemplateTypeName(info, null);
Node extendsClause = clazz.getSecondChild();
// Look at the extends clause and/or JSDoc info to find a super class. Use generics from the
// JSDoc to supplement the extends type when available.
ObjectType baseType = findSuperClassFromNodes(extendsClause, info);
builder.inferInheritance(info, baseType);
// Look for an explicit constructor.
Node constructor = NodeUtil.getEs6ClassConstructorMemberFunctionDef(clazz);
if (constructor != null) {
constructor = constructor.getOnlyChild(); // We want the FUNCTION, not the member.
}
if (constructor != null) {
// Note: constructor should have the following structure:
// MEMBER_FUNCTION_DEF [jsdoc_info]
// FUNCTION
// NAME
// PARAM_LIST ...
// BLOCK ...
// NodeUtil.getFirstPropMatchingKey returns the FUNCTION node.
JSDocInfo ctorInfo = NodeUtil.getBestJSDocInfo(constructor);
builder.inferConstructorParameters(constructor.getSecondChild(), ctorInfo);
} else if (extendsClause.isEmpty()) {
// No explicit constructor and no superclass: constructor is no-args.
builder.inferImplicitConstructorParameters(new Node(Token.PARAM_LIST));
} else {
// No explicit constructor, but we have a superclass. If we know its type, then copy its
// constructor arguments (and templates). If not, make the constructor arguments unknown.
// TODO(sdh): consider allowing attaching constructor @param annotations somewhere else?
FunctionType extendsCtor = baseType != null ? baseType.getConstructor() : null;
if (extendsCtor != null) {
// Known superclass: copy the parameters node.
builder.inferImplicitConstructorParameters(extendsCtor.getParametersNode().cloneTree());
} else {
// Unresolveable extends clause: suppress typechecking.
builder.inferImplicitConstructorParameters(
typeRegistry.createParametersWithVarArgs(
typeRegistry.getNativeType(JSTypeNative.UNKNOWN_TYPE)));
}
}
// TODO(sdh): Handle template parameters. The constructor should store all parameters,
// while the instance type should only have the class-level parameters?
// Add the type for the "constructor" property.
FunctionType classType = builder.buildAndRegister();
if (classType.isConstructor()) {
// NOTE: This logic is similar to the goog.inherits handling in
// ClosureCodingConvention#applySubclassRelationship. If this logic is modified
// it is likely that code needs to be modified as well.
// Notice that constructor functions do not need to be covariant on the superclass.
// So if G extends F, new G() and new F() can accept completely different argument
// types, but G.prototype.constructor needs to be covariant on F.prototype.constructor.
// To get around this, we just turn off type-checking on arguments and return types
// of G.prototype.constructor.
// NOTE: For final classes we could do better here and retain the parameter types.
FunctionType qmarkCtor = classType.forgetParameterAndReturnTypes();
ObjectType classPrototypeType = classType.getPrototypeProperty();
classPrototypeType.defineDeclaredProperty("constructor", qmarkCtor, constructor);
}
if (classType.hasInstanceType()) {
Property classPrototype = classType.getSlot("prototype");
// SymbolTable users expect the class prototype and actual class to have the same
// declaration node.
classPrototype.setNode(lvalueNode != null ? lvalueNode : classPrototype.getNode());
}
return classType;
}
/**
* Look at the {@code extends} clause to find the instance type being extended.
* Returns {@code null} if there is no such clause, and unknown if the type cannot
* be determined.
*/
@Nullable
private ObjectType findSuperClassFromNodes(Node extendsNode, @Nullable JSDocInfo info) {
if (extendsNode.isEmpty()) {
// No extends clause: return null.
return null;
}
JSType ctorType = extendsNode.getJSType();
if (ctorType == null) {
if (extendsNode.isQualifiedName()) {
// Look up qualified names in the scope (types won't be set on the AST until inference).
TypedVar var = currentScope.getVar(extendsNode.getQualifiedName());
if (var != null) {
ctorType = var.getType();
}
// If that doesn't work, then fall back on the registry
if (ctorType == null) {
return ObjectType.cast(
typeRegistry.getType(
currentScope,
extendsNode.getQualifiedName(),
extendsNode.getSourceFileName(),
extendsNode.getLineno(),
extendsNode.getCharno()));
}
} else {
// Anything TypedScopeCreator can infer has already been read off the AST. This is likely
// a CALL or GETELEM, which are unknown until TypeInference. Instead, ignore it for now,
// require an @extends tag in the JSDoc, and verify correctness in TypeCheck.
if (info == null || !info.hasBaseType()) {
report(JSError.make(extendsNode, DYNAMIC_EXTENDS_WITHOUT_JSDOC));
}
}
}
if (ctorType != null) {
if (ctorType.isConstructor() || ctorType.isInterface()) {
return ctorType.toMaybeFunctionType().getInstanceType();
} else if (ctorType.isUnknownType()) {
// The constructor could have an unknown type for cases where it is dynamically
// created or passed in from elsewhere.
// e.g. with a mixin pattern
// function mixinSomething(ctor) {
// return class extends ctor { ... };
// }
// In that case consider the super class instance type to be unknown.
return ctorType.toMaybeObjectType();
}
}
// We couldn't determine the type, so for TypedScope creation purposes we will treat it as if
// there were no extends clause. TypeCheck will give a more precise error later.
return null;
}
/**
* Creates a new function type, based on the given nodes.
*
* This handles two cases that are semantically very different, but
* are not mutually exclusive:
* - A function literal that needs a type attached to it (called from
* defineClassLiteral with a non-null FUNCTION node for rValue).
* - An assignment expression with function-type info in the JsDoc
* (called from getDeclaredType on a stub (rValue == null) or alias
* (rValue is a qualified name).
*
* All parameters are optional, and we will do the best we can to create
* a function type.
*
* This function will always create a function type, so only call it if
* you're sure that's what you want.
*
* @param rValue The function node.
* @param name the function's name
* @param info the {@link JSDocInfo} attached to the function definition
* @param lvalueNode The node where this function is being
* assigned. For example, {@code A.prototype.foo = ...} would be used to
* determine that this function is a method of A.prototype. May be
* null to indicate that this is not being assigned to a qualified name.
*/
private FunctionType createFunctionTypeFromNodes(
@Nullable Node rValue,
@Nullable String name,
@Nullable JSDocInfo info,
@Nullable Node lvalueNode) {
// Check for an alias.
if (rValue != null && rValue.isQualifiedName() && lvalueNode != null) {
TypedVar var = currentScope.getVar(rValue.getQualifiedName());
if (var != null && var.getType() != null && var.getType().isFunctionType()) {
FunctionType aliasedType = var.getType().toMaybeFunctionType();
if (aliasedType.isConstructor() || aliasedType.isInterface()) {
// TODO(nick): Remove this. This should already be handled by normal type resolution.
if (name != null) {
typeRegistry.declareType(currentScope, name, aliasedType.getInstanceType());
}
checkFunctionAliasAnnotations(lvalueNode, aliasedType, info);
return aliasedType;
}
}
}
// No alias: look for an explicit @type in JSDocInfo.
if (info != null && info.hasType()) {
JSType type = info.getType().evaluate(currentScope, typeRegistry);
// Known to be not null since we have the FUNCTION token there.
type = type.restrictByNotNullOrUndefined();
if (type.isFunctionType()) {
FunctionType functionType = type.toMaybeFunctionType();
functionType.setJSDocInfo(info);
return functionType;
}
}
// No alias or explicit @type, so look for a function literal, or @param/@return.
Node errorRoot = rValue == null ? lvalueNode : rValue;
boolean isFnLiteral = rValue != null && rValue.isFunction();
Node fnRoot = isFnLiteral ? rValue : null;
Node parametersNode = isFnLiteral ? rValue.getSecondChild() : null;
// If this function is being assigned as a property on a type, try finding the owner type
// and the property name.
// This is easy to do for class members because the owner type is on the CLASS node and
// the property name is the MEMBER_FUNCTION_DEF/GETTER_DEF/SETTER_DEF string.
// For other functions, we rely on NodeUtil.getBestLValueOwner.
Node classRoot =
lvalueNode != null && lvalueNode.getParent().isClassMembers()
? lvalueNode.getGrandparent()
: null;
Node ownerNode = NodeUtil.getBestLValueOwner(lvalueNode);
ObjectType ownerType = null;
String propName = null;
if (classRoot != null) {
// Static members are owned by the constructor, non-statics are owned by the prototype.
ownerType = JSType.toMaybeFunctionType(classRoot.getJSType());
if (!lvalueNode.isStaticMember() && ownerType != null) {
ownerType = ((FunctionType) ownerType).getPrototype();
}
propName = lvalueNode.isComputedProp() ? null : lvalueNode.getString();
} else {
String ownerName = NodeUtil.getBestLValueName(ownerNode);
TypedVar ownerVar = ownerName != null ? currentScope.getVar(ownerName) : null;
if (ownerVar != null) {
ownerType = ObjectType.cast(ownerVar.getType());
}
if (ownerName != null && name != null) {
// TODO(b/111621092): Use the AST rather than manipulating strings here.
checkState(
name.startsWith(ownerName), "Expected \"%s\" to start with \"%s\"", name, ownerName);
propName = name.substring(ownerName.length() + 1);
}
}
ObjectType prototypeOwner = getPrototypeOwnerType(ownerType);
TemplateTypeMap prototypeOwnerTypeMap = null;
if (prototypeOwner != null && prototypeOwner.getTypeOfThis() != null) {
prototypeOwnerTypeMap = prototypeOwner.getTypeOfThis().getTemplateTypeMap();
}
// Find the type of any overridden function.
FunctionType overriddenType = null;
if (ownerType != null && propName != null) {
// the type of the property this overrides, not necessarily a function.
JSType overriddenPropType =
findOverriddenProperty(ownerType, propName, prototypeOwnerTypeMap);
if (overriddenPropType != null) {
// Overridden getters and setters need special handling because we declare
// getters/setters as simple properties with their respective return/parameter type. This
// causes a split during inference where left and right sides of a getter/setter
// declaration will be inferred to have different types; if the left side has type `T`,
// the right side will be some function type involving `T`.
if (lvalueNode.isGetterDef()) {
// Convert `number` to `function(): number`
overriddenType = typeRegistry.createFunctionType(overriddenPropType);
} else if (lvalueNode.isSetterDef()) {
// Convert `number` to `function(number): undefined`
overriddenType =
typeRegistry.createFunctionType(getNativeType(VOID_TYPE), overriddenPropType);
} else if (overriddenPropType.isFunctionType()) {
// for cases where we override a non-method (e.g. a number) with a method, don't put the
// non-method type (e.g. number) on the function.
// Instead do some basic inference to create a function type.
// we will warn during typechecking for an invalid override, but we don't want to put a
// non-function type on this function because that will interfere with type inference
// inside the function.
overriddenType = overriddenPropType.toMaybeFunctionType();
}
}
}
AstFunctionContents contents = fnRoot != null ? new AstFunctionContents(fnRoot) : null;
if (functionsWithNonEmptyReturns.contains(fnRoot)) {
contents.recordNonEmptyReturn();
}
FunctionTypeBuilder builder =
new FunctionTypeBuilder(name, compiler, errorRoot, currentScope)
.setContents(contents)
.setDeclarationScope(
lvalueNode != null ? getLValueRootScope(lvalueNode) : currentScope)
.inferFromOverriddenFunction(overriddenType, parametersNode)
.inferKind(info)
.inferClosurePrimitive(info)
.inferTemplateTypeName(info, prototypeOwner)
.inferInheritance(info, null);
if (info == null || !info.hasReturnType()) {
// when there is no @return annotation, look for inline return type declaration
if (rValue != null && rValue.isFunction() && rValue.getFirstChild() != null) {
JSDocInfo nameDocInfo = rValue.getFirstChild().getJSDocInfo();
builder.inferReturnType(nameDocInfo, true);
}
} else {
builder.inferReturnType(info, false);
}
// Infer the context type.
JSType fallbackReceiverType = null;
if (ownerType != null
&& ownerType.isFunctionPrototypeType()
&& ownerType.getOwnerFunction().hasInstanceType()) {
fallbackReceiverType = ownerType.getOwnerFunction().getInstanceType();
} else if (ownerType != null
&& ownerType.isFunctionType()
&& ownerType.toMaybeFunctionType().hasInstanceType()
&& lvalueNode != null
&& lvalueNode.isStaticMember()) {
// Limit this case to members of ctors and interfaces decalared using `static`. Most
// namespaces, like object literals, are assumed to declare free functions, so we exclude
// them. Additionally, methods *assigned* to a ctor, especially an ES5 ctor, were never
// designed with static polymorphism in mind, so excluding them preserves their assumptions.
fallbackReceiverType = ownerType;
} else if (ownerNode != null && ownerNode.isThis()) {
fallbackReceiverType = currentScope.getTypeOfThis();
}
FunctionType fnType =
builder
.inferThisType(info, fallbackReceiverType)
.inferParameterTypes(parametersNode, info)
.buildAndRegister();
// Do some additional validation for constructors and interfaces.
if (fnType.hasInstanceType() && lvalueNode != null) {
Property prototypeSlot = fnType.getSlot("prototype");
// We want to make sure that the function and its prototype are declared at the same node.
// This consistency is helpful to users of SymbolTable, because everything gets declared at
// the same place.
prototypeSlot.setNode(lvalueNode);
}
return fnType;
}
/**
* Checks that the annotations in {@code info} are compatible with the aliased {@code type}.
* Any errors will be reported at {@code n}, which should be the qualified name node.
*/
private void checkFunctionAliasAnnotations(Node n, FunctionType type, JSDocInfo info) {
if (info == null) {
return;
}
String annotation = null;
if (info.usesImplicitMatch()) {
if (!type.isStructuralInterface()) {
annotation = "@record";
}
} else if (info.isInterface()) {
if (!type.isInterface()) {
annotation = "@interface";
}
} else if (info.isConstructor() && !type.isConstructor()) {
annotation = "@constructor";
}
// TODO(sdh): consider checking @template, @param, @return, and/or @this.
if (annotation != null
// TODO(sdh): Remove this extra check once TypeScript stops passing us duplicate
// conflicting externs. In particular, TS considers everything an interface, but Closure
// externs mark most things as @constructor. The load order is not always the same, so
// the error can show up in either the generated TS externs file or in our own extern.
&& (!n.isFromExterns() || annotation.equals("@record"))) {
report(JSError.make(n, INCOMPATIBLE_ALIAS_ANNOTATION, annotation, n.getQualifiedName()));
}
}
private ObjectType getPrototypeOwnerType(ObjectType ownerType) {
if (ownerType != null && ownerType.isFunctionPrototypeType()) {
return ownerType.getOwnerFunction();
}
return null;
}
/**
* Find the property that's being overridden on this type, if any.
*
* Said property could be a method, field, getter, or setter. We don't distinguish between
* these when looking up a property type.
*/
private JSType findOverriddenProperty(
ObjectType ownerType, String propName, TemplateTypeMap typeMap) {
JSType result = null;
// First, check to see if the property is implemented
// on a superclass.
JSType propType = ownerType.getPropertyType(propName);
if (propType != null && !propType.isUnknownType()) {
result = propType;
} else {
// If it's not, then check to see if it's implemented
// on an implemented interface.
for (ObjectType iface : ownerType.getCtorImplementedInterfaces()) {
propType = iface.getPropertyType(propName);
if (propType != null && !propType.isUnknownType()) {
result = propType;
break;
}
}
}
if (result != null && typeMap != null && !typeMap.isEmpty()) {
result = result.visit(TemplateTypeReplacer.forPartialReplacement(typeRegistry, typeMap));
}
return result;
}
/**
* Creates a new enum type, based on the given nodes.
*
*
This handles two cases that are semantically very different, but are not mutually
* exclusive: (1) An object literal that needs an enum type attached to it. (2) An assignment
* expression with an enum tag in the JsDoc.
*
*
This function will always create an enum type, so only call it if you're sure that's what
* you want.
*
* @param rValue The right-hand side of the enum, or null if none.
* @param lValue The left-hand side of the enum.
* @param name The qualified name of the enum
* @param info The {@link JSDocInfo} attached to the enum definition.
*/
private EnumType createEnumTypeFromNodes(
@Nullable Node rValue, @Nullable String name, Node lValue, JSDocInfo info) {
checkNotNull(info);
checkState(info.hasEnumParameterType());
checkState(
lValue != null || rValue != null,
"An enum initializer should come from either an lvalue or rvalue");
EnumType enumType = null;
if (rValue != null && rValue.isQualifiedName()) {
// Handle an aliased enum. Note that putting @enum on an enum alias is optional. If the
// rValue is not an enum, then this assignment errors during TypeCheck.
TypedVar var = currentScope.getVar(rValue.getQualifiedName());
if (var != null && var.getType() != null && var.getType().isEnumType()) {
enumType = var.getType().toMaybeEnumType();
}
}
if (enumType == null) {
JSType elementsType = info.getEnumParameterType().evaluate(currentScope, typeRegistry);
enumType = typeRegistry.createEnumType(name, rValue, elementsType);
if (rValue != null && rValue.isObjectLit()) {
// collect enum elements
Node key = rValue.getFirstChild();
while (key != null) {
if (key.isComputedProp()) {
report(JSError.make(key, INVALID_ENUM_KEY));
key = key.getNext();
continue;
}
String keyName = key.getString();
Preconditions.checkNotNull(keyName, "Invalid enum key: %s", key);
enumType.defineElement(keyName, key);
key = key.getNext();
}
}
}
if (name != null) {
typeRegistry.declareType(currentScope, name, enumType.getElementsType());
}
if (rValue == null || !(rValue.isObjectLit() || rValue.isQualifiedName())) {
report(JSError.make(lValue != null ? lValue : rValue, ENUM_INITIALIZER));
}
return enumType;
}
/** Responsible for defining typed variable "slots". */
class SlotDefiner {
Node declarationNode;
String variableName;
TypedScope scope;
// default is no type and a type may be inferred later
JSType type = null;
boolean allowLaterTypeInference = true;
// TODO(bradfordcsmith): Once all the logic needed for ES_2017 features has been added,
// make the API to this class more restrictive to avoid accidental misuse.
// e.g. There will probably always be a declarationNode, so make it a constructor
// parameter.
/** @param declarationNode the defining NAME or GETPROP or object literal key node. */
SlotDefiner forDeclarationNode(Node declarationNode) {
this.declarationNode = declarationNode;
return this;
}
SlotDefiner readVariableNameFromDeclarationNode() {
// Only qualified name nodes can use this method to get the variable name
// Object literal keys will have to compute their names themselves.
// TODO(bradfordcsmith): Clean up these checks of the parent.
Node parent = declarationNode.getParent();
if (declarationNode.isName()) {
checkArgument(
parent.isFunction()
|| parent.isClass()
|| NodeUtil.isNameDeclaration(parent)
|| parent.isParamList()
|| (parent.isRest() && parent.getParent().isParamList())
|| parent.isCatch());
} else {
checkArgument(
declarationNode.isGetProp() && (parent.isAssign() || parent.isExprResult()));
}
variableName = declarationNode.getQualifiedName();
return this;
}
// TODO(bradfordcsmith): maybe change to withVariableName(). Need to make these names more
// consistent.
SlotDefiner forVariableName(String variableName) {
this.variableName = variableName;
return this;
}
/**
* Sets the scope in which the variable should be declared.
*
*
If the given name is a qualified name, this scope should be the scope in which the root
* of the name is (or will later be) declared.
*/
SlotDefiner inScope(TypedScope scope) {
this.scope = checkNotNull(scope);
return this;
}
SlotDefiner withType(@Nullable JSType type) {
this.type = type;
return this;
}
SlotDefiner allowLaterTypeInference(boolean allowLaterTypeInference) {
this.allowLaterTypeInference = allowLaterTypeInference;
return this;
}
/**
* Define the slot and do related work.
*
*
At minimum the declaration node and variable name must have been set.
*/
void defineSlot() {
checkNotNull(declarationNode, "declarationNode not set");
checkNotNull(variableName, "variableName not set");
checkState(allowLaterTypeInference || type != null, "null type but inference not allowed");
checkState(!variableName.isEmpty());
checkNotNull(scope);
Node parent = declarationNode.getParent();
TypedScope scopeToDeclareIn = scope;
boolean isGlobalVar = declarationNode.isName() && scopeToDeclareIn.isGlobal();
boolean shouldDeclareOnGlobalThis = isGlobalVar && (parent.isVar() || parent.isFunction());
// TODO(sdh): Remove this special case. It is required to reproduce the original
// non-block-scoped behavior, which is depended on in several places including
// https://github.com/angular/tsickle/issues/761. But it's more correct to always
// declare on the owner scope. Once all the bugs are fixed, this should be removed.
// We may be able to get by with checking a "declared" function's source for jsdoc.
if (scopeToDeclareIn != currentHoistScope
&& scopeToDeclareIn.isGlobal()
&& scopeToDeclareIn.hasOwnSlot(variableName)) {
scopeToDeclareIn = currentHoistScope;
}
// The input may be null if we are working with a AST snippet. So read
// the extern info from the node.
// declared in closest scope?
CompilerInput input = compiler.getInput(inputId);
if (!scopeToDeclareIn.canDeclare(variableName)) {
TypedVar oldVar = scopeToDeclareIn.getVar(variableName);
validator.expectUndeclaredVariable(
sourceName, input, declarationNode, parent, oldVar, variableName, type);
} else {
if (type != null) {
setDeferredType(declarationNode, type);
}
declare(
scopeToDeclareIn,
variableName,
declarationNode,
type,
input,
allowLaterTypeInference);
}
// We need to do some additional work for constructors and interfaces.
FunctionType fnType = JSType.toMaybeFunctionType(type);
if (fnType != null
// We don't want to look at empty function types.
&& !type.isEmptyType()) {
// We want to make sure that when we declare a new instance type
// (with @constructor) that there's actually a ctor for it.
// This doesn't apply to structural constructors (like
// function(new:Array). Checking the constructed type against
// the variable name is a sufficient check for this.
if (fnType.isConstructor() || fnType.isInterface()) {
finishConstructorDefinition(
declarationNode, variableName, fnType, scopeToDeclareIn, input);
}
}
if (shouldDeclareOnGlobalThis) {
ObjectType globalThis = typeRegistry.getNativeObjectType(GLOBAL_THIS);
if (allowLaterTypeInference) {
globalThis.defineInferredProperty(
variableName,
type == null ? getNativeType(JSTypeNative.NO_TYPE) : type,
declarationNode);
} else {
globalThis.defineDeclaredProperty(variableName, type, declarationNode);
}
}
if (isGlobalVar
&& "Window".equals(variableName)
&& type != null
&& type.isFunctionType()
&& type.isConstructor()) {
FunctionType globalThisCtor =
typeRegistry.getNativeObjectType(GLOBAL_THIS).getConstructor();
globalThisCtor.getInstanceType().clearCachedValues();
globalThisCtor.getPrototype().clearCachedValues();
globalThisCtor.setPrototypeBasedOn((type.toMaybeFunctionType()).getInstanceType());
}
}
}
/**
* Declares a variable with the given {@code name} and {@code type} on the given {@code scope},
* returning the newly-declared {@link TypedVar}. Additionally checks the {@link
* #escapedVarNames} and {@link #assignedVarNames} maps (which were populated during the {@link
* FirstOrderFunctionAnalyzer} and marks the result as escaped or assigned exactly once if
* appropriate.
*/
private TypedVar declare(
TypedScope scope, String name, Node n, JSType type, CompilerInput input, boolean inferred) {
TypedVar var = scope.declare(name, n, type, input, inferred);
ScopedName scopedName = ScopedName.of(name, scope.getRootNode());
if (escapedVarNames.contains(scopedName)) {
var.markEscaped();
}
if (assignedVarNames.count(scopedName) == 1) {
var.markAssignedExactlyOnce();
}
return var;
}
private void finishConstructorDefinition(
Node declarationNode,
String variableName,
FunctionType fnType,
TypedScope scopeToDeclareIn,
CompilerInput input) {
// Declare var.prototype in the scope chain.
FunctionType superClassCtor = fnType.getSuperClassConstructor();
Property prototypeSlot = fnType.getSlot("prototype");
String prototypeName = variableName + ".prototype";
// There are some rare cases where the prototype will already
// be declared. See TypedScopeCreatorTest#testBogusPrototypeInit.
// Fortunately, other warnings will complain if this happens.
TypedVar prototypeVar = scopeToDeclareIn.getVar(prototypeName);
if (prototypeVar != null && prototypeVar.scope == scopeToDeclareIn) {
scopeToDeclareIn.undeclare(prototypeVar);
}
scopeToDeclareIn.declare(
prototypeName,
declarationNode,
prototypeSlot.getType(),
input,
// declared iff there's an explicit supertype
superClassCtor == null
|| superClassCtor.getInstanceType().isEquivalentTo(getNativeType(OBJECT_TYPE)));
}
/** Check if the given node is a property of a name in the global scope. */
private boolean isLValueRootedInGlobalScope(Node n) {
return getLValueRootScope(n).isGlobal();
}
/** Return the scope for the name of the given node. */
private TypedScope getLValueRootScope(Node n) {
Node root = NodeUtil.getBestLValueRoot(n);
if (root != null) {
if (root.isName()) {
Node nameParent = root.getParent();
switch (nameParent.getToken()) {
case VAR:
return currentHoistScope;
case LET:
case CONST:
case CLASS:
case FUNCTION:
case PARAM_LIST:
case CATCH:
return currentScope;
case ITER_REST:
case OBJECT_REST:
// TODO(bradfordcsmith): Handle array destructuring REST
checkState(nameParent.getParent().isParamList(), nameParent);
return currentScope;
default:
if (isGoogModuleExports(root)) {
// Ensure that 'exports = class {}' in a goog.module returns the module scope.
return currentScope;
}
TypedVar var = currentScope.getVar(root.getString());
if (var != null) {
return var.getScope();
}
}
} else if (root.isThis() || root.isSuper()) {
// We want the enclosing function scope, or the global scope if not in a function.
return currentHoistScope.getScopeOfThis();
}
}
return currentHoistScope.getGlobalScope();
}
/**
* Look for a type declaration on a property assignment (in an ASSIGN or an object literal key).
*
* @param info The doc info for this property.
* @param lValue The l-value node.
* @param rValue The node that {@code n} is being initialized to, or {@code null} if this is a
* stub declaration.
* @param declaredRValueTypeSupplier A supplier for the declared type of the rvalue, used for
* destructuring declarations where we have to do additional work on the rvalue.
*/
JSType getDeclaredType(
JSDocInfo info,
Node lValue,
@Nullable Node rValue,
@Nullable Supplier declaredRValueTypeSupplier) {
if (info != null && info.hasType()) {
return getDeclaredTypeInAnnotation(lValue, info);
} else if (rValue != null
&& rValue.isFunction()
&& shouldUseFunctionLiteralType(
JSType.toMaybeFunctionType(rValue.getJSType()), info, lValue)) {
return rValue.getJSType();
} else if (rValue != null && rValue.isClass()) {
return rValue.getJSType();
} else if (info != null) {
if (info.hasEnumParameterType()) {
if (rValue != null && rValue.isObjectLit()) {
return rValue.getJSType();
} else {
return createEnumTypeFromNodes(rValue, lValue.getQualifiedName(), lValue, info);
}
} else if (info.isConstructorOrInterface()) {
FunctionType fnType =
createFunctionTypeFromNodes(rValue, lValue.getQualifiedName(), info, lValue);
if (rValue == null && !lValue.isFromExterns()) {
report(
JSError.make(
lValue,
fnType.isConstructor() ? CTOR_INITIALIZER : IFACE_INITIALIZER,
lValue.getQualifiedName()));
}
return fnType;
}
}
// Check if this is constant, and if it has a known type.
if (NodeUtil.isConstantDeclaration(compiler.getCodingConvention(), info, lValue)
|| isGoogModuleExports(lValue)) {
if (rValue != null) {
JSType rValueType = getDeclaredRValueType(lValue, rValue);
declareAliasTypeIfRvalueIsAliasable(
lValue, rValue.getQualifiedNameObject(), rValueType, currentScope);
if (rValueType != null) {
return rValueType;
}
} else if (declaredRValueTypeSupplier != null) {
RValueInfo rvalueInfo = declaredRValueTypeSupplier.get();
if (rvalueInfo != null) {
declareAliasTypeIfRvalueIsAliasable(
lValue, rvalueInfo.qualifiedName, rvalueInfo.type, currentScope);
if (rvalueInfo.type != null) {
return rvalueInfo.type;
}
}
}
}
if (info != null && FunctionTypeBuilder.isFunctionTypeDeclaration(info)) {
String fnName = lValue.getQualifiedName();
return createFunctionTypeFromNodes(null, fnName, info, lValue);
}
if (isValidTypedefDeclaration(lValue, info)) {
return getNativeType(JSTypeNative.NO_TYPE);
}
return null;
}
/**
* For a const alias, like `const alias = other.name`, this may declare `alias` as a type name,
* depending on what other.name is defined to be.
*
* This method recognizes three kinds of type aliases: @typedefs, @constructor/@interface
* types, and @enums.
*
*
Given any of those three types, this method redeclares the aliasing name in the
* typeRegistry. For @typedefs and global @enums, this method also marks the qualified name
* referring to the type as non-nullable by default.
*/
private void declareAliasTypeIfRvalueIsAliasable(
Node lValue,
@Nullable QualifiedName rValue,
@Nullable JSType rValueType,
TypedScope rValueLookupScope) {
declareAliasTypeIfRvalueIsAliasable(
lValue.getQualifiedName(), lValue, rValue, rValueType, rValueLookupScope, currentScope);
}
/**
* For a const alias, like `const alias = other.name`, this may declare `alias` as a type name,
* depending on what other.name is defined to be.
*
*
NOTE: in most cases, call the version with fewer arguments. This version only exists to
* handle goog.declareLegacyNamespace, which is strange compared to normal type aliasing because
* 1) there's no GETPROP node representing the lvalue and 2) the type is declared in the global
* scope, not the current module-local scope.
*
* @param lValueName the fully qualified lValue name, if any. If null, all this method will do
* is propagate the @typedef Node annotation to actualLvalueNode.
* @param aliasDeclarationScope The scope in which to declare the alias name. In most cases,
* this should just be the {@link #currentScope}.
*/
private void declareAliasTypeIfRvalueIsAliasable(
@Nullable String lValueName,
@Nullable Node actualLvalueNode,
@Nullable QualifiedName rValue,
@Nullable JSType rValueType,
TypedScope rValueLookupScope,
TypedScope aliasDeclarationScope) {
// NOTE: this allows some strange patterns such allowing instance properties
// to be aliases of constructors, and then creating a local alias of that to be
// used as a type name. Consider restricting this.
if (rValue == null) {
return;
}
// Look for a @typedef annotation on the definition node
Node definitionNode = getDefinitionNode(rValue, rValueLookupScope);
if (definitionNode != null) {
JSType typedefType = definitionNode.getTypedefTypeProp();
if (typedefType != null) {
// Propagate typedef type to typedef aliases.
actualLvalueNode.setTypedefTypeProp(typedefType);
if (lValueName != null) {
typeRegistry.identifyNonNullableName(aliasDeclarationScope, lValueName);
typeRegistry.declareType(aliasDeclarationScope, lValueName, typedefType);
}
return;
}
}
if (lValueName == null) {
return;
}
// Check if the provided rValueType indicates that we should declare this type
// Note that we only look for enums and constructors/interfaces here: this step cannot work
// for @typedefs. The 'type' of the TypedVar representing a @typedef'd name is the None type,
// not the @typedef'd type.
if (rValueType != null
&& rValueType.isFunctionType()
&& rValueType.toMaybeFunctionType().hasInstanceType()) {
// Look for @constructor/@interface by checking if the RHS has an instance type
FunctionType functionType = rValueType.toMaybeFunctionType();
typeRegistry.declareType(aliasDeclarationScope, lValueName, functionType.getInstanceType());
return;
}
if (rValueType != null && rValueType.isEnumType()) {
// Look for cases where the rValue is an Enum namespace
typeRegistry.declareType(
aliasDeclarationScope, lValueName, rValueType.toMaybeEnumType().getElementsType());
typeRegistry.identifyNonNullableName(aliasDeclarationScope, lValueName);
}
}
/** Whether this lvalue is either `exports`, `exports.x`, or a string key in `exports = {x}`. */
boolean isGoogModuleExports(Node lValue) {
if (module == null) {
return false;
}
if (undeclaredNamesForClosure.contains(lValue)) {
return true;
}
return lValue.isStringKey()
&& lValue.getParent().isObjectLit()
&& lValue.getGrandparent().isAssign()
&& undeclaredNamesForClosure.contains(lValue.getParent().getPrevious());
}
/** Returns the AST node associated with the definition, if any. */
private Node getDefinitionNode(QualifiedName qname, TypedScope scope) {
if (qname.isSimple()) {
TypedVar var = scope.getVar(qname.getComponent());
return var != null ? var.getNameNode() : null;
}
ObjectType parent = ObjectType.cast(scope.lookupQualifiedName(qname.getOwner()));
return parent != null ? parent.getPropertyDefSite(qname.getComponent()) : null;
}
/**
* Check for common idioms of a typed R-value assigned to a const L-value.
*
*
Normally, we would only want this sort of propagation to happen under type inference. But
* we want a declared const to be nameable in a type annotation, so we need to figure out the
* type before we try to resolve the annotation.
*
* @param lValue is the lvalue node if this is a simple assignment, null for destructuring
*/
private JSType getDeclaredRValueType(@Nullable Node lValue, Node rValue) {
// If rValue has a type-cast, we use the type in the type-cast.
JSDocInfo rValueInfo = rValue.getJSDocInfo();
if (rValue.isCast() && rValueInfo != null && rValueInfo.hasType()) {
return rValueInfo.getType().evaluate(currentScope, typeRegistry);
}
// Check if the type has already been computed during scope-creation.
// This is mostly useful for literals like BOOLEAN, NUMBER, STRING, and
// OBJECT_LITERAL
JSType type = rValue.getJSType();
if (type != null && !type.isUnknownType()) {
return type;
}
// If rValue is a name, try looking it up in the current scope.
if (rValue.isQualifiedName()) {
return currentScope.lookupQualifiedName(rValue.getQualifiedNameObject());
}
// Check for simple invariant operations, such as "!x" or "+x" or "''+x"
if (NodeUtil.isBooleanResult(rValue)) {
return getNativeType(BOOLEAN_TYPE);
}
if (NodeUtil.isNumericResult(rValue)) {
return getNativeType(NUMBER_TYPE);
}
if (NodeUtil.isStringResult(rValue)) {
return getNativeType(STRING_TYPE);
}
if (rValue.isNew() && rValue.getFirstChild().isQualifiedName()) {
JSType targetType =
currentScope.lookupQualifiedName(rValue.getFirstChild().getQualifiedNameObject());
if (targetType != null) {
FunctionType fnType = targetType.restrictByNotNullOrUndefined().toMaybeFunctionType();
if (fnType != null && fnType.hasInstanceType()) {
return fnType.getInstanceType();
}
}
}
// Check for a very specific JS idiom:
// var x = x || TYPE;
// This is used by Closure's base namespace for esoteric
// reasons, so we only really care about that case.
if (rValue.isOr()) {
Node firstClause = rValue.getFirstChild();
Node secondClause = firstClause.getNext();
boolean namesMatch =
firstClause.isName()
&& lValue != null
&& lValue.isName()
&& firstClause.getString().equals(lValue.getString());
if (namesMatch) {
type = secondClause.getJSType();
if (type != null && !type.isUnknownType()) {
return type;
}
}
}
return null;
}
/**
* Look for class-defining calls.
* Because JS has no 'native' syntax for defining classes,
* this is often very coding-convention dependent and business-logic heavy.
*/
void checkForClassDefiningCalls(Node n) {
SubclassRelationship relationship =
codingConvention.getClassesDefinedByCall(n);
if (relationship != null) {
ObjectType superClass =
TypeValidator.getInstanceOfCtor(
currentScope.lookupQualifiedName(QualifiedName.of(relationship.superclassName)));
ObjectType subClass =
TypeValidator.getInstanceOfCtor(
currentScope.lookupQualifiedName(QualifiedName.of(relationship.subclassName)));
if (superClass != null && subClass != null) {
// superCtor and subCtor might be structural constructors
// (like {function(new:Object)}) so we need to resolve them back
// to the original ctor objects.
FunctionType superCtor = superClass.getConstructor();
FunctionType subCtor = subClass.getConstructor();
if (superCtor != null && subCtor != null) {
codingConvention.applySubclassRelationship(
new NominalTypeBuilder(superCtor, superClass),
new NominalTypeBuilder(subCtor, subClass),
relationship.type);
}
}
}
String singletonGetterClassName = codingConvention.getSingletonGetterClassName(n);
if (singletonGetterClassName != null) {
ObjectType objectType = ObjectType.cast(
typeRegistry.getType(currentScope, singletonGetterClassName));
if (objectType != null) {
FunctionType functionType = objectType.getConstructor();
if (functionType != null) {
FunctionType getterType = typeRegistry.createFunctionType(objectType);
codingConvention.applySingletonGetter(
new NominalTypeBuilder(functionType, objectType), getterType);
}
}
}
DelegateRelationship delegateRelationship = codingConvention.getDelegateRelationship(n);
if (delegateRelationship != null) {
applyDelegateRelationship(delegateRelationship);
}
ObjectLiteralCast objectLiteralCast = codingConvention.getObjectLiteralCast(n);
if (objectLiteralCast != null) {
if (objectLiteralCast.diagnosticType == null) {
ObjectType type = ObjectType.cast(
typeRegistry.getType(currentScope, objectLiteralCast.typeName));
if (type != null && type.getConstructor() != null) {
setDeferredType(objectLiteralCast.objectNode, type);
objectLiteralCast.objectNode.putBooleanProp(Node.REFLECTED_OBJECT, true);
} else {
report(JSError.make(n, CONSTRUCTOR_EXPECTED));
}
} else {
report(JSError.make(n, objectLiteralCast.diagnosticType));
}
}
}
/**
* Apply special properties that only apply to delegates.
*/
private void applyDelegateRelationship(
DelegateRelationship delegateRelationship) {
ObjectType delegatorObject =
ObjectType.cast(typeRegistry.getType(currentScope, delegateRelationship.delegator));
ObjectType delegateBaseObject =
ObjectType.cast(typeRegistry.getType(currentScope, delegateRelationship.delegateBase));
ObjectType delegateSuperObject =
ObjectType.cast(
typeRegistry.getType(currentScope, codingConvention.getDelegateSuperclassName()));
if (delegatorObject != null
&& delegateBaseObject != null
&& delegateSuperObject != null) {
FunctionType delegatorCtor = delegatorObject.getConstructor();
FunctionType delegateBaseCtor = delegateBaseObject.getConstructor();
FunctionType delegateSuperCtor = delegateSuperObject.getConstructor();
if (delegatorCtor != null && delegateBaseCtor != null && delegateSuperCtor != null) {
FunctionParamBuilder functionParamBuilder = new FunctionParamBuilder(typeRegistry);
functionParamBuilder.addRequiredParams(getNativeType(U2U_CONSTRUCTOR_TYPE));
FunctionType findDelegate =
typeRegistry.createFunctionType(
typeRegistry.createNullableType(delegateBaseObject),
functionParamBuilder.build());
FunctionType delegateProxy =
typeRegistry.createConstructorType(
delegateBaseObject.getReferenceName() + DELEGATE_PROXY_SUFFIX /* name */,
null /* source */,
null /* parameters */,
null /* returnType */,
null /* templateKeys */,
false /* isAbstract */);
delegateProxy.setPrototypeBasedOn(delegateBaseObject);
codingConvention.applyDelegateRelationship(
new NominalTypeBuilder(delegateSuperCtor, delegateSuperObject),
new NominalTypeBuilder(delegateBaseCtor, delegateBaseObject),
new NominalTypeBuilder(delegatorCtor, delegatorObject),
(ObjectType) delegateProxy.getTypeOfThis(),
findDelegate);
delegateProxyCtors.add(delegateProxy);
}
}
}
/**
* Declare the symbol for a qualified name in the global scope.
*
* @param info The doc info for this property.
* @param n A top-level GETPROP node (it should not be contained inside
* another GETPROP).
* @param parent The parent of {@code n}.
* @param rhsValue The node that {@code n} is being initialized to,
* or {@code null} if this is a stub declaration.
*/
void maybeDeclareQualifiedName(NodeTraversal t, JSDocInfo info,
Node n, Node parent, Node rhsValue) {
boolean isTypedef = isValidTypedefDeclaration(n, info);
if (isTypedef) {
declareTypedefType(n, info);
}
Node ownerNode = n.getFirstChild();
String ownerName = ownerNode.getQualifiedName();
String qName = n.getQualifiedName();
String propName = n.getLastChild().getString();
checkArgument(qName != null && ownerName != null);
// Precedence of type information on GETPROPs:
// 1) @type annotation / @enum annotation
// 2) ASSIGN to FUNCTION literal
// 3) @param/@return annotation (with no function literal)
// 4) ASSIGN to something marked @const
// 5) ASSIGN to anything else
//
// 1, 3, and 4 are declarations, 5 is inferred, and 2 is a declaration iff
// the function has JsDoc or has not been declared before.
//
// FUNCTION literals are special because TypedScopeCreator is very smart
// about getting as much type information as possible for them.
// Determining type for #1 + #2 + #3 + #4
JSType valueType = getDeclaredType(info, n, rhsValue, null);
if (valueType == null && rhsValue != null) {
// Determining type for #5
valueType = rhsValue.getJSType();
}
// Function prototypes are special.
// It's a common JS idiom to do:
// F.prototype = { ... };
// So if F does not have an explicitly declared super type,
// allow F.prototype to be redefined arbitrarily.
if ("prototype".equals(propName)) {
TypedVar qVar = currentScope.getVar(qName);
if (qVar != null) {
// If the programmer has declared that F inherits from Super,
// and they assign F.prototype to an object literal,
// then they are responsible for making sure that the object literal's
// implicit prototype is set up appropriately. We just obey
// the @extends tag.
ObjectType qVarType = ObjectType.cast(qVar.getType());
if (qVarType != null && rhsValue != null && rhsValue.isObjectLit()) {
typeRegistry.resetImplicitPrototype(
rhsValue.getJSType(), qVarType.getImplicitPrototype());
} else if (!qVar.isTypeInferred()) {
// If the programmer has declared that F inherits from Super,
// and they assign F.prototype to some arbitrary expression,
// there's not much we can do. We just ignore the expression,
// and hope they've annotated their code in a way to tell us
// what props are going to be on that prototype.
return;
}
qVar.getScope().undeclare(qVar);
}
}
if (valueType == null) {
if (parent.isExprResult()) {
// t is mutable so make sure to capture the current state before the lambda.
boolean isExtern = t.getInput() != null && t.getInput().isExtern();
deferredActions.put(
currentScope.getRootNode(), () -> resolveStubDeclaration(n, isExtern, ownerName));
}
return;
}
boolean inferred = isQualifiedNameInferred(qName, n, info, rhsValue, valueType);
if (!inferred) {
ObjectType ownerType = getObjectSlot(ownerName);
if (ownerType != null) {
// need ownernode - is it always just first child of n?
declarePropertyIfNamespaceType(t, ownerType, n, valueType);
}
// If the property is already declared, the error will be
// caught when we try to declare it in the current scope.
new SlotDefiner()
.forDeclarationNode(n)
.forVariableName(qName)
.inScope(getLValueRootScope(n))
.withType(valueType)
.allowLaterTypeInference(inferred)
.defineSlot();
}
}
/**
* Determines whether a qualified name is inferred.
* NOTE(nicksantos): Determining whether a property is declared or not
* is really really obnoxious.
*
* The problem is that there are two (equally valid) coding styles:
*
* (function() {
* /* The authoritative definition of goog.bar. /
* goog.bar = function() {};
* })();
*
* function f() {
* goog.bar();
* /* Reset goog.bar to a no-op. /
* goog.bar = function() {};
* }
*
* In a dynamic language with first-class functions, it's very difficult
* to know which one the user intended without looking at lots of
* contextual information (the second example demonstrates a small case
* of this, but there are some really pathological cases as well).
*
* The current algorithm checks if either the declaration has
* JsDoc type information, or @const with a known type,
* or a function literal with a name we haven't seen before.
*/
private boolean isQualifiedNameInferred(
@Nullable String qName,
Node n,
@Nullable JSDocInfo info,
@Nullable Node rhsValue,
JSType valueType) {
// Prototypes of constructors and interfaces are always declared.
if (qName != null && qName.endsWith(".prototype")) {
String className = qName.substring(0, qName.lastIndexOf(".prototype"));
TypedVar slot = currentScope.getVar(className);
JSType classType = slot == null ? null : slot.getType();
if (classType != null && (classType.isConstructor() || classType.isInterface())) {
return false;
}
}
// If the jsdoc or RHS specifies a concrete type, it's not inferred.
if (info != null
&& (info.hasType()
|| info.hasEnumParameterType()
|| isValidTypedefDeclaration(n, info)
|| isConstantDeclarationWithKnownType(info, n, valueType)
|| FunctionTypeBuilder.isFunctionTypeDeclaration(info)
|| (rhsValue != null && rhsValue.isFunction()))) {
return false;
}
// If this is a typed goog.module export, it's not inferred.
if (valueType != null && !valueType.isUnknownType() && isGoogModuleExports(n)) {
return false;
}
// At this point, we're pretty sure it's inferred, since there's neither
// useful jsdoc info, nor a useful const or doc'd function RHS. But
// there's still one case where it may still not be: if the RHS is a
// class or function that is not
// (1) a scoped qualified name (i.e. this.b.c or super.b.c),
// (2) already declared in a scope,
// (3) assigned in a conditional block, or
// (4) escaped to a closure,
// then we treat it as if it is declared, rather than inferred.
// Stubs and other values are always considered inferred at this point.
if (rhsValue == null || (!rhsValue.isFunction() && !rhsValue.isClass())) {
return true;
}
// "Scoped" qualified names (e.g. this.b.c or super.d) are inferred.
if (!n.isUnscopedQualifiedName()) {
return true;
}
// If this qname is already declared then treat this definition as inferred.
TypedScope ownerScope = getLValueRootScope(n);
if (ownerScope != null && ownerScope.hasOwnSlot(qName)) {
return true;
}
// Check if this is in a conditional block.
// Functions assigned in conditional blocks are inferred.
if (hasControlStructureAncestor(n.getParent())) {
return true;
}
// Check if this is assigned in an inner scope.
// Functions assigned in inner scopes are inferred.
if (ownerScope != null
&& escapedVarNames.contains(ScopedName.of(qName, ownerScope.getRootNode()))) {
return true;
}
return false;
}
/**
* Given a `goog.provide()` or legacy `goog.module()` call and implicit ProvidedName, declares
* the name in the global scope.
*/
void declareProvidedNs(Node provideCall, ProvidedName providedName) {
// Redefine this name if we haven't already added a provide definition.
// Note: in some cases, this will cause a redefinition error.
ObjectType anonymousObjectType = typeRegistry.createAnonymousObjectType(null);
new SlotDefiner()
.inScope(currentScope.getGlobalScope())
.allowLaterTypeInference(false)
.forVariableName(providedName.getNamespace())
.forDeclarationNode(provideCall)
.withType(anonymousObjectType)
.defineSlot();
QualifiedName namespace = QualifiedName.of(providedName.getNamespace());
if (!namespace.isSimple()) {
JSType ownerType = currentScope.lookupQualifiedName(namespace.getOwner());
if (ownerType != null && ownerType.isObjectType()) {
ownerType
.toMaybeObjectType()
.defineDeclaredProperty(namespace.getComponent(), anonymousObjectType, provideCall);
}
}
}
private boolean isConstantDeclarationWithKnownType(JSDocInfo info, Node n, JSType valueType) {
return NodeUtil.isConstantDeclaration(compiler.getCodingConvention(), info, n)
&& valueType != null
&& !valueType.isUnknownType();
}
private boolean hasControlStructureAncestor(Node n) {
while (!(n.isScript() || n.isFunction())) {
if (NodeUtil.isControlStructure(n)) {
return true;
}
n = n.getParent();
}
return false;
}
/**
* Find the ObjectType associated with the given slot.
* @param slotName The name of the slot to find the type in.
* @return An object type, or null if this slot does not contain an object.
*/
private ObjectType getObjectSlot(String slotName) {
TypedVar ownerVar = currentScope.getVar(slotName);
if (ownerVar != null) {
JSType ownerVarType = ownerVar.getType();
return ObjectType.cast(
ownerVarType == null ? null : ownerVarType.restrictByNotNullOrUndefined());
}
return null;
}
/**
* When a class has a stub for a property, and the property exists on a super interface,
* use that type.
*/
private JSType getInheritedInterfacePropertyType(ObjectType obj, String propName) {
if (obj != null && obj.isFunctionPrototypeType()) {
FunctionType f = obj.getOwnerFunction();
for (ObjectType i : f.getImplementedInterfaces()) {
if (i.hasProperty(propName)) {
return i.getPropertyType(propName);
}
}
}
return null;
}
/**
* Resolve any type-less stub declarations to unknown types if we could not find types for them
* during traversal. This method is only called as a deferred action after the root node is
* visted.
*/
void resolveStubDeclaration(Node n, boolean isExtern, String ownerName) {
String qName = n.getQualifiedName();
String propName = n.getLastChild().getString();
// TODO(b/111216910): should this be getLValueRoot(n).hasOwnSlot(qName)?
if (currentScope.hasOwnSlot(qName)) {
return;
}
// If we see a stub property, make sure to register this property
// in the type registry.
ObjectType ownerType = getObjectSlot(ownerName);
JSType inheritedType = getInheritedInterfacePropertyType(ownerType, propName);
JSType stubType = inheritedType == null ? unknownType : inheritedType;
new SlotDefiner()
.forDeclarationNode(n)
.readVariableNameFromDeclarationNode()
.inScope(getLValueRootScope(n))
.withType(stubType)
.allowLaterTypeInference(true)
.defineSlot();
if (ownerType != null && (isExtern || ownerType.isFunctionPrototypeType())) {
// If this is a stub for a prototype, just declare it
// as an unknown type. These are seen often in externs.
ownerType.defineInferredProperty(
propName, stubType, n);
} else {
typeRegistry.registerPropertyOnType(
propName, ownerType == null ? stubType : ownerType);
}
}
/**
* Returns whether this is a valid declaration of a @typedef.
*
* @param candidate A qualified name node.
* @param info JSDoc comments.
*/
private boolean isValidTypedefDeclaration(Node candidate, @Nullable JSDocInfo info) {
if (info == null || !info.hasTypedefType()) {
return false;
}
return candidate.isQualifiedName();
}
/** Declares a typedef'd name in the {@link JSTypeRegistry}. */
void declareTypedefType(Node candidate, JSDocInfo info) {
String typedef = candidate.getQualifiedName();
// TODO(nicksantos|user): This is a terrible, terrible hack
// to bail out on recursive typedefs. We'll eventually need
// to handle these properly.
typeRegistry.declareType(currentScope, typedef, unknownType);
JSType realType = info.getTypedefType().evaluate(currentScope, typeRegistry);
if (realType == null) {
report(JSError.make(candidate, MALFORMED_TYPEDEF, typedef));
} else {
candidate.setTypedefTypeProp(realType);
}
typeRegistry.overwriteDeclaredType(currentScope, typedef, realType);
}
void declarePropertyIfNamespaceType(
NodeTraversal t, ObjectType ownerType, Node getpropNode, JSType valueType) {
checkState(getpropNode.isGetProp());
String propName = getpropNode.getLastChild().getString();
// Only declare this as an official property if it has not been
// declared yet.
if (ownerType.hasOwnProperty(propName) && !ownerType.isPropertyTypeInferred(propName)) {
return;
}
// Define the property if any of the following are true:
// (1) it's a non-native extern type. Native types are excluded here because we don't
// want externs of the form "/** @type {!Object} */ var api = {}; api.foo;" to
// cause a property "foo" to be declared on Object.
// (2) it's a non-instance type. This primarily covers static properties on
// constructors (which are FunctionTypes, not InstanceTypes).
// (3) it's an assignment to 'this', which covers instance properties assigned in
// constructors or other methods.
boolean isNonNativeExtern =
t.getInput() != null && t.getInput().isExtern() && !ownerType.isNativeObjectType();
if (isNonNativeExtern
|| !ownerType.isInstanceType()
|| getpropNode.getFirstChild().isThis()) {
// If the property is undeclared or inferred, declare it now.
ownerType.defineDeclaredProperty(propName, valueType, getpropNode);
}
}
} // end AbstractScopeBuilder
/** A shallow traversal of the global scope to build up all classes, functions, and methods. */
private final class NormalScopeBuilder extends AbstractScopeBuilder {
NormalScopeBuilder(TypedScope scope, @Nullable Module module) {
super(scope, module);
}
@Override
void visitPreorder(NodeTraversal t, Node n, Node parent) {
// Handle hoisted functions ahead of time, when preorder-visiting their enclosing block.
if (NodeUtil.isStatementParent(n) || n.isExport()) {
for (Node child = n.getFirstChild(); child != null; child = child.getNext()) {
if (NodeUtil.isHoistedFunctionDeclaration(child)) {
defineFunctionLiteral(child);
}
}
}
// Create any child block scopes "pre-order" as we see them.
//
// This is required because hoisted or qualified names defined in earlier blocks might be
// referred to later outside the block. This isn't a big deal in most cases since a NamedType
// will be created and resolved later, but if a NamedType is used for a superclass, we lose a
// lot of valuable checking. Recursing into child blocks immediately prevents this from being
// a problem.
//
// We don't traverse into CLASSes because we haven't yet have created the class-type on which
// to assign members. We'll do this on the way back up (post-order) instead, after the
// class-type has been attached to the AST.
if (parent != null && NodeUtil.createsBlockScope(n) && !n.isClass()) {
createScope(n, currentScope);
}
// All other functions (and classes, etc) are handled when we see the actual function node.
if (n.isFunction() && !NodeUtil.isHoistedFunctionDeclaration(n)) {
defineFunctionLiteral(n);
}
}
@Override
void visitPostorder(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
case CALL:
checkForClassDefiningCalls(n);
break;
case ASSIGN:
// Handle initialization of properties.
// We only allow qualified name declarations of the form
// /** @type {number} */ a.b.c = rhs;
// TODO(b/77597706): Ensure that CheckJSDoc warns for JSDoc on assignments not to
// qualified names, e.g.
// /** @type {number} */ [a.b.c] = someArr;
Node firstChild = n.getFirstChild();
if (firstChild.isGetProp() && firstChild.isQualifiedName()) {
maybeDeclareQualifiedName(t, n.getJSDocInfo(), firstChild, n, firstChild.getNext());
} else if (undeclaredNamesForClosure.contains(firstChild)) {
defineAssignAsIfDeclaration(n);
}
break;
case CATCH:
defineCatch(n);
break;
case VAR:
case LET:
case CONST:
defineVars(n);
break;
case GETPROP:
codingConvention.checkForCallingConventionDefinitions(n, delegateCallingConventions);
// Handle stubbed properties.
if (parent.isExprResult() && n.isQualifiedName()) {
maybeDeclareQualifiedName(t, n.getJSDocInfo(), n, parent, null);
}
break;
case CLASS:
// Analyse CLASS child-scopes now because later code in this scope may assign
// properties to these class-types. We want to ensure declarations within the CLASS have
// priority.
createScope(n, currentScope);
break;
case EXPR_RESULT:
Collection names = providedNamesFromCall.get(n);
if (names != null) {
for (ProvidedName name : names) {
declareProvidedNs(n, name);
}
}
break;
case EXPORT:
if (n.getBooleanProp(Node.EXPORT_DEFAULT)) {
JSType declaredType = n.getOnlyChild().getJSType();
currentScope.declare(
Export.DEFAULT_EXPORT_NAME,
n,
declaredType,
compiler.getInput(NodeUtil.getInputId(n)),
/* inferred= */ declaredType == null);
}
break;
default:
break;
}
}
} // end NormalScopeBuilder
/**
* Scope builder subclass for function scopes, which only contain bleeding function names and
* parameter names. The main function body is handled by the a NormalScopeBuilder on the function
* block.
*/
private final class FunctionScopeBuilder extends AbstractScopeBuilder {
FunctionScopeBuilder(TypedScope scope) {
super(scope, null);
}
@Override
void visitPreorder(NodeTraversal t, Node n, Node parent) {
if (parent == null) {
handleFunctionInputs();
} else if (n.isFunction()) {
defineFunctionLiteral(n);
}
}
/** Handle bleeding functions and function parameters. */
void handleFunctionInputs() {
// Handle bleeding functions. These are defined as function expressions which have a non-empty
// name, which we declare in the FUNCTION scope. Function declarations are hoisted and are
// already declared in the containing scope; ignore those.
Node fnNode = currentScope.getRootNode();
Node fnNameNode = fnNode.getFirstChild();
String fnName = fnNameNode.getString();
if (!fnName.isEmpty() && NodeUtil.isFunctionExpression(fnNode)) {
new SlotDefiner()
.forDeclarationNode(fnNameNode)
.forVariableName(fnName)
.inScope(currentScope)
.withType(fnNode.getJSType())
.allowLaterTypeInference(false)
.defineSlot();
}
declareParameters(fnNode);
}
/** Declares all of a function's parameters inside the function's scope. */
void declareParameters(Node functionNode) {
if (NodeUtil.isBundledGoogModuleCall(functionNode.getParent())) {
// Skip declaring 'exports' for a goog.loadModule(function(exports) {.
// We pretend that any assignments to 'exports' in the body are actually declarations.
return;
}
Node astParameters = functionNode.getSecondChild();
Node iifeArgumentNode = null;
if (NodeUtil.isInvocationTarget(functionNode)) {
iifeArgumentNode = functionNode.getNext();
}
FunctionType functionType = JSType.toMaybeFunctionType(functionNode.getJSType());
if (functionType != null) {
Node jsDocParameters = functionType.getParametersNode();
if (jsDocParameters != null) {
Node jsDocParameter = jsDocParameters.getFirstChild();
for (Node astParameter : astParameters.children()) {
if (iifeArgumentNode != null && iifeArgumentNode.isSpread()) {
// don't try inferring types from spreads in iifes because we don't know how
// many items are in the iterable.
iifeArgumentNode = null;
}
JSType declaredType = jsDocParameter == null ? unknownType : jsDocParameter.getJSType();
declareNamesInPositionalParameter(astParameter, declaredType, iifeArgumentNode);
if (jsDocParameter != null) {
jsDocParameter = jsDocParameter.getNext();
}
if (iifeArgumentNode != null) {
iifeArgumentNode = iifeArgumentNode.getNext();
}
}
}
// Also add template params to the scope so that JSTypeRegistry can find them (they
// were already registered by FunctionTypeBuilder).
JSDocInfo info = NodeUtil.getBestJSDocInfo(functionNode);
if (info != null) {
Iterable templateNames =
Iterables.concat(info.getTemplateTypeNames(), info.getTypeTransformations().keySet());
if (!Iterables.isEmpty(templateNames)) {
CompilerInput input = getCompilerInput();
JSType voidType = typeRegistry.getNativeType(VOID_TYPE);
// Declare any template names in the function scope. This means that if someone shadows
// an outer variable FOO with a @template FOO and refers to FOO inside the method, we
// will treat it as undefined, rather than the correct type, which could lead to weird
// errors. Ideally we'd have a "don't use me" type that gives an error at use.
for (String name : templateNames) {
if (!currentScope.canDeclare(name)) {
validator.expectUndeclaredVariable(
NodeUtil.getSourceName(functionNode),
input,
functionNode,
functionNode.getParent(),
currentScope.getVar(name),
name,
voidType);
}
currentScope.declare(name, functionNode, voidType, input, /* inferred= */ false);
}
}
}
}
} // end declareParameters
/**
* Declares the name(s) in a positional AST parameter in the scope.
*
* @param astParameter the positional parameter node
* @param declaredParameterType the declared parameter type, or the unknown type if there is
* none
* @param iifeArgumentNode the corresponding argument from the iife, if in an iife. e.g. for
* `(function (x) {}(3);` this would be `3`.
*/
private void declareNamesInPositionalParameter(
Node astParameter, JSType declaredParameterType, @Nullable Node iifeArgumentNode) {
JSType paramType = declaredParameterType;
boolean isInferred = paramType.equals(unknownType);
if (iifeArgumentNode != null && isInferred) {
String argumentName = iifeArgumentNode.getQualifiedName();
TypedVar argumentVar =
argumentName == null || currentScope.getParent() == null
? null
: currentScope.getParent().getVar(argumentName);
if (argumentVar != null && !argumentVar.isTypeInferred()) {
paramType = argumentVar.getType();
}
}
if (paramType == null) {
paramType = unknownType;
}
switch (astParameter.getToken()) {
case NAME: // function f(x) {}
declareSingleParameterName(isInferred, astParameter, paramType);
break;
case ITER_REST: // function f(...x) {}
// rest parameter is actually an array of the type specified in the JSDoc
Node param = astParameter.getFirstChild();
ObjectType arrayType = typeRegistry.getNativeObjectType(ARRAY_TYPE);
JSType restParamType = typeRegistry.createTemplatizedType(arrayType, paramType);
if (param.isName()) {
declareSingleParameterName(isInferred, astParameter.getFirstChild(), restParamType);
} else {
// function f(...{length}) {}
declareDestructuringParameter(isInferred, param, restParamType);
}
break;
case DEFAULT_VALUE: // function f(x = 3) {} or function f([x] = []) {}
Node actualParam = astParameter.getFirstChild();
if (actualParam.isName()) {
declareSingleParameterName(isInferred, actualParam, paramType);
} else {
declareDestructuringParameter(isInferred, actualParam, paramType);
}
break;
case ARRAY_PATTERN: // function f([x]) {}
case OBJECT_PATTERN: // function f({x}) {}
declareDestructuringParameter(isInferred, astParameter, paramType);
break;
default:
throw new IllegalStateException("Unexpected function parameter node " + astParameter);
}
}
/**
* Declares all names inside a destructuring pattern in a parameter list in the scope if we can
* find a non-unknown type for them.
*
* Unknown typed parameters are always treated as inferred, not declared. TypeInference may
* later give them a better inferred type than unknown, but they will never become declared.
*
*
NOTE: currently, there are some less-than-ideal aspects to how we do this. If the pattern
* type is an unresolved NamedType, then we can't lookup properties on it (to find the
* individual parameter types) until after name resolution. The current state is to defer to
* TypeInference to type those parameters, with the drawback that they are 'inferred', not
* 'declared', and so any type can be assigned to them. In the future we will just enforce
* typing each parameter individually: relevant issue
*/
private void declareDestructuringParameter(
boolean isInferred, Node pattern, JSType patternType) {
for (DestructuredTarget target :
DestructuredTarget.createAllNonEmptyTargetsInPattern(
typeRegistry, patternType, pattern)) {
JSType parameterType = target.inferTypeWithoutUsingDefaultValue();
if (target.getNode().isDestructuringPattern()) {
declareDestructuringParameter(isInferred, target.getNode(), parameterType);
} else {
Node paramName = target.getNode();
checkState(paramName.isName(), "Expected all parameters to be names, got %s", paramName);
if (parameterType == null || parameterType.isUnknownType()) {
JSDocInfo paramJSDoc = paramName.getJSDocInfo();
if (paramJSDoc != null && paramJSDoc.hasType()) {
// see if the parameter has its own inline JSDoc, and use that unless we already have
// a type from @param JSDoc.
// TODO(b/112651122): this should happen inside FunctionTypeBuilder, so that we can
// check that calls to the function match the inline JSDoc.
// TODO(b/111523967): we should also report a
// warning if the inline and non-inline JSDoc conflict.
parameterType =
typeRegistry.evaluateTypeExpression(paramJSDoc.getType(), currentScope);
isInferred = false;
} else {
// note - these parameters may get better types during TypeInference
isInferred = true;
}
}
declareSingleParameterName(isInferred, paramName, parameterType);
}
}
}
private void declareSingleParameterName(boolean isInferred, Node name, JSType type) {
new SlotDefiner()
.forDeclarationNode(name)
.forVariableName(name.getString())
.inScope(currentScope)
.withType(type)
.allowLaterTypeInference(isInferred)
.defineSlot();
}
} // end FunctionScopeBuilder
/**
* Scope builder subclass for class scopes, which only contain a bleeding class name. Methods
* are handled by FunctionScopeBuilder and NormalScopeBuilder for the bodies.
*/
private final class ClassScopeBuilder extends AbstractScopeBuilder {
private Table getterSetterTypes = null;
ClassScopeBuilder(TypedScope scope) {
super(scope, null);
}
@Override
void visitPreorder(NodeTraversal t, Node n, Node parent) {
// These are not descended into, so must be done preorder
if (!n.isFunction()) {
return;
}
if (NodeUtil.isEs6Constructor(n)) {
// Constructor has already been analyzed, so pull that here.
setDeferredType(n, currentScope.getRootNode().getJSType());
} else {
defineFunctionLiteral(n);
}
}
@Override
void visitPostorder(NodeTraversal t, Node n, Node parent) {
if (n.isName()
&& parent == currentScope.getRootNode()
&& NodeUtil.isClassExpression(parent)) {
// Declare bleeding class name in scope. Pull the type off the AST.
checkState(!n.getString().isEmpty()); // anonymous classes have EMPTY nodes, not NAME
new SlotDefiner()
.forDeclarationNode(n)
.readVariableNameFromDeclarationNode()
.inScope(currentScope)
.withType(parent.getJSType())
.allowLaterTypeInference(false)
.defineSlot();
} else if (NodeUtil.isEs6ConstructorMemberFunctionDef(n)) {
// Ignore "constructor" since it has special handling in `createClassTypeFromNodes()`.
} else if (n.isMemberFunctionDef()) {
defineMemberFunction(n);
} else if (n.isGetterDef() || n.isSetterDef()) {
defineGetterSetter(n);
}
}
void defineMemberFunction(Node n) {
ObjectType ownerType = determineOwnerTypeForClassMember(n);
ownerType.defineDeclaredProperty(n.getString(), n.getLastChild().getJSType(), n);
}
void defineGetterSetter(Node n) {
// GETTER_DEF -> CLASS_MEMBERS -> CLASS
if (getterSetterTypes == null) {
this.getterSetterTypes = HashBasedTable.create();
}
FunctionType methodType = n.getLastChild().getJSType().toMaybeFunctionType();
JSType propertyType =
n.isGetterDef()
? determineGetterType(methodType)
: Iterables.getFirst(methodType.getParameterTypes(), null);
propertyType = propertyType != null ? propertyType : unknownType;
String name = n.getString();
JSType previousType =
getterSetterTypes.get(name, n.isGetterDef() ? Token.SETTER_DEF : Token.GETTER_DEF);
if (previousType != null && !previousType.equals(propertyType)) {
// TODO(sdh): make this not an error - instead, store the getter and setter types separately
report(
JSError.make(
n,
CONFLICTING_GETTER_SETTER_TYPE,
name,
n.isGetterDef() ? propertyType.toString() : previousType.toString(),
n.isGetterDef() ? previousType.toString() : propertyType.toString()));
} else if (previousType == null) {
ObjectType ownerType = determineOwnerTypeForClassMember(n);
ownerType.defineDeclaredProperty(name, propertyType, n);
getterSetterTypes.put(name, n.getToken(), propertyType);
}
}
/**
* Returns the owner type for a class member function, getter, or setter.
*
* For a member on class C, this is either `C` for a static member or `C.prototype` for a
* nonstatic member.
*/
private ObjectType determineOwnerTypeForClassMember(Node member) {
// MEMBER_FUNCTION_DEF -> CLASS_MEMBERS -> CLASS or
// GETTER_DEF -> CLASS_MEMBERS -> CLASS
Node ownerNode = member.getGrandparent();
checkState(ownerNode.isClass());
ObjectType ownerType = ownerNode.getJSType().toMaybeFunctionType();
if (!member.isStaticMember()) {
ownerType = ((FunctionType) ownerType).getPrototype();
}
return ownerType;
}
/** Returns the type of the getter, falling back on unknown if the return type was inferred. */
private JSType determineGetterType(FunctionType methodType) {
// TODO(sdh): consider only falling back on unknown if the function body is empty? But we
// need to not report a conflicting type error if there's different unknowns.
return !methodType.isReturnTypeInferred() ? methodType.getReturnType() : unknownType;
}
} // end ClassScopeBuilder
/**
* Does a first-order function analysis that just looks at simple things like what variables are
* escaped, and whether 'this' is used.
*
*
The syntactic scopes created in this traversal are also stored for later use.
*/
private class FirstOrderFunctionAnalyzer extends AbstractScopedCallback {
@Override
public void enterScope(NodeTraversal t) {
Scope scope = t.getScope();
Node root = scope.getRootNode();
untypedScopes.put(root, scope);
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if (t.inGlobalScope()) {
// The first-order function analyzer looks at two types of variables:
//
// 1) Local variables that are assigned in inner scopes ("escaped vars")
//
// 2) Local variables that are assigned more than once.
//
// We treat all global variables as escaped by default, so there's
// no reason to do this extra computation for them.
return;
}
Scope containerScope = (Scope) t.getClosestContainerScope();
// Record function with returns or arrow functions without bodies
if ((n.isReturn() && n.hasChildren())
|| (NodeUtil.isBlocklessArrowFunctionResult(n))) {
functionsWithNonEmptyReturns.add(containerScope.getRootNode());
}
// Be careful of bleeding functions, which create variables
// in the inner scope, not the scope where the name appears.
if (n.isName() && NodeUtil.isLValue(n) && !NodeUtil.isBleedingFunctionName(n)) {
String name = n.getString();
Scope scope = t.getScope();
Var var = scope.getVar(name);
// TODO(sdh): consider checking hasSameHoistScope instead of container scope here and
// below. This will detect function(a) { a.foo = bar } as an escaped qualified name,
// which seems like the right thing to do (but could possibly break things?)
// Doing so will allow removing the warning on TypeCheckTest#testIssue1024b.
if (var != null) {
Scope ownerScope = var.getScope();
if (ownerScope.isLocal()) {
ScopedName scopedName = ScopedName.of(name, ownerScope.getRootNode());
assignedVarNames.add(scopedName);
if (!containerScope.hasSameContainerScope(ownerScope)) {
escapedVarNames.add(scopedName);
}
}
}
} else if (n.isGetProp() && n.isUnscopedQualifiedName() && NodeUtil.isLValue(n)) {
String name = NodeUtil.getRootOfQualifiedName(n).getString();
Scope scope = t.getScope();
Var var = scope.getVar(name);
if (var != null) {
Scope ownerScope = var.getScope();
if (ownerScope.isLocal() && !containerScope.hasSameContainerScope(ownerScope)) {
escapedVarNames.add(ScopedName.of(n.getQualifiedName(), ownerScope.getRootNode()));
}
}
}
}
}
@Override
public boolean hasBlockScope() {
return true;
}
}