com.google.javascript.jscomp.ProcessClosureProvidesAndRequires Maven / Gradle / Ivy
/*
* Copyright 2019 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 com.google.common.annotations.GwtIncompatible;
import com.google.common.base.Preconditions;
import com.google.javascript.rhino.IR;
import com.google.javascript.rhino.JSDocInfo;
import com.google.javascript.rhino.JSDocInfoBuilder;
import com.google.javascript.rhino.JSTypeExpression;
import com.google.javascript.rhino.Node;
import com.google.javascript.rhino.Token;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.annotation.Nullable;
/**
* Replaces goog.provide calls, removes goog.{require,requireType,forwardDeclare} calls and verifies
* that each goog.{require,requireType} has a corresponding goog.provide.
*
* We expect all goog.modules and goog.requires in modules to have been rewritten. This is why
* all remaining require/requireType calls must refer to a goog.provide, although the original JS
* code may contain goog.requires of a goog.module.
*
*
This is designed to work during a hotswap pass, under the assumption that no rewriting has
* been done of goog.provides and definitions other than this pass.
*
*
This also annotates all provided namespace definitions `a.b = {};` with {@link
* Node#IS_NAMESPACE} so that later passes know they refer to a goog.provide'd namespace.
*
*
If modules have not been rewritten, this pass also includes legacy Closure module namespaces
* in the list of {@link ProvidedName}s.
*/
class ProcessClosureProvidesAndRequires implements HotSwapCompilerPass {
// The root Closure namespace
private static final String GOOG = "goog";
private final AbstractCompiler compiler;
private final JSModuleGraph moduleGraph;
// Use a LinkedHashMap because the goog.provides must be processed in a deterministic order.
private final Map providedNames = new LinkedHashMap<>();
private final CheckLevel requiresLevel;
private final PreprocessorSymbolTable preprocessorSymbolTable;
// If this is true, rewriting will not remove any goog.provide or goog.require calls
private final boolean preserveGoogProvidesAndRequires;
private final List requiresToBeRemoved = new ArrayList<>();
// Whether this instance has already rewritten goog.provides, which can only happen once
private boolean hasRewritingOccurred = false;
private final Set forwardDeclaresToRemove = new HashSet<>();
private final Set previouslyProvidedDefinitions = new HashSet<>();
private final TypedScope globalTypedScope;
private final AstFactory astFactory;
ProcessClosureProvidesAndRequires(
AbstractCompiler compiler,
@Nullable PreprocessorSymbolTable preprocessorSymbolTable,
CheckLevel requiresLevel,
boolean preserveGoogProvidesAndRequires,
@Nullable TypedScope globalTypedScope) {
checkArgument(globalTypedScope == null || globalTypedScope.isGlobal());
this.compiler = compiler;
this.preprocessorSymbolTable = preprocessorSymbolTable;
this.moduleGraph = compiler.getModuleGraph();
this.requiresLevel = requiresLevel;
this.preserveGoogProvidesAndRequires = preserveGoogProvidesAndRequires;
this.globalTypedScope = globalTypedScope;
this.astFactory = compiler.createAstFactory();
}
/** When invoked as compiler pass, we rewrite all provides and requires. */
@Override
public void process(Node externs, Node root) {
rewriteProvidesAndRequires(externs, root);
}
@Override
public void hotSwapScript(Node scriptRoot, Node originalRoot) {
// TODO(bashir): Implement a real hot-swap version instead and make it fully
// consistent with the full version.
this.compiler.process(this);
}
/** Collects all goog.provides in the given namespace and warns on invalid code */
Map collectProvidedNames(Node externs, Node root) {
if (this.providedNames.isEmpty()) {
// goog is special-cased because it is provided in Closure's base library.
providedNames.put(GOOG, new ProvidedName(GOOG, null, null, false /* implicit */, false));
NodeTraversal.traverseRoots(compiler, new CollectDefinitions(), externs, root);
}
return this.providedNames;
}
/**
* Rewrites all provides and requires in the given namespace.
*
* Call this instead of {@link #collectProvidedNames(Node, Node)} if you want rewriting.
*/
void rewriteProvidesAndRequires(Node externs, Node root) {
checkState(!hasRewritingOccurred, "Cannot call rewriteProvidesAndRequires twice per instance");
hasRewritingOccurred = true;
collectProvidedNames(externs, root);
for (ProvidedName pn : providedNames.values()) {
pn.replace();
}
deleteNamespaceInitializationsFromPreviousProvides();
for (Node closureRequire : requiresToBeRemoved) {
compiler.reportChangeToEnclosingScope(closureRequire);
closureRequire.detach();
}
for (Node forwardDeclare : forwardDeclaresToRemove) {
NodeUtil.deleteNode(forwardDeclare, compiler);
}
}
private class CollectDefinitions implements NodeTraversal.Callback {
@Override
public boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
// Don't recurse into modules, which cannot have goog.provides. We do need to handle legacy
// goog.modules, but we do that quickly here rather than descending all the way into them.
// We completely ignore ES modules and CommonJS modules.
if ((n.isModuleBody() && n.getParent().getBooleanProp(Node.GOOG_MODULE))
|| NodeUtil.isBundledGoogModuleScopeRoot(n)) {
Node googModuleCall = n.getFirstChild();
String closureNamespace = googModuleCall.getFirstChild().getSecondChild().getString();
Node maybeLegacyNamespaceCall = googModuleCall.getNext();
if (maybeLegacyNamespaceCall != null
&& NodeUtil.isGoogModuleDeclareLegacyNamespaceCall(maybeLegacyNamespaceCall)) {
processLegacyModuleCall(closureNamespace, googModuleCall, t.getModule());
}
return false;
}
return !n.isModuleBody();
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
case CALL:
Node left = n.getFirstChild();
if (left.isGetProp()) {
Node name = left.getFirstChild();
if (name.isName() && GOOG.equals(name.getString())) {
// For the sake of simplicity, we report code changes
// when we see a provides/requires, and don't worry about
// reporting the change when we actually do the replacement.
String methodName = name.getNext().getString();
switch (methodName) {
case "require":
case "requireType":
if (isValidPrimitiveCall(t, n)) {
processRequireCall(t, n, parent);
}
break;
case "provide":
if (isValidPrimitiveCall(t, n)) {
processProvideCall(t, n, parent);
}
break;
case "forwardDeclare":
if (isValidPrimitiveCall(t, n)) {
processForwardDeclare(n, parent);
}
break;
}
}
}
break;
case ASSIGN:
case NAME:
// If this is an assignment to a provided name, remove the provided object.
handleCandidateProvideDefinition(t, n, parent);
break;
case EXPR_RESULT:
handleStubDefinition(t, n);
break;
case CLASS:
if (t.inGlobalHoistScope() && !NodeUtil.isClassExpression(n)) {
String name = n.getFirstChild().getString();
ProvidedName pn = providedNames.get(name);
if (pn != null) {
compiler.report(
JSError.make(n, ProcessClosurePrimitives.CLASS_NAMESPACE_ERROR, name));
}
}
break;
case FUNCTION:
// If this is a declaration of a provided named function, this is an
// error. Hoisted functions will explode if they're provided.
if (t.inGlobalHoistScope() && NodeUtil.isFunctionDeclaration(n)) {
String name = n.getFirstChild().getString();
ProvidedName pn = providedNames.get(name);
if (pn != null) {
compiler.report(
JSError.make(n, ProcessClosurePrimitives.FUNCTION_NAMESPACE_ERROR, name));
}
}
break;
default:
break;
}
}
}
private boolean isValidPrimitiveCall(NodeTraversal t, Node n) {
// Ignore invalid primitives if we didn't strip module sugar.
if (compiler.getOptions().shouldPreserveGoogModule()) {
return true;
}
return t.inGlobalHoistScope() && n.getParent().isExprResult();
}
/** Handles a goog.require or goog.requireType call. */
private void processRequireCall(NodeTraversal t, Node n, Node parent) {
Node left = n.getFirstChild();
Node arg = left.getNext();
String method = left.getFirstChild().getNext().getString();
if (verifyLastArgumentIsString(left, arg)) {
String ns = arg.getString();
ProvidedName provided = providedNames.get(ns);
if (provided == null || !provided.isExplicitlyProvided()) {
} else {
JSModule providedModule = provided.explicitModule;
if (!provided.isFromExterns()) {
checkNotNull(providedModule, n);
JSModule module = t.getModule();
// A cross-chunk goog.require must match a goog.provide in an earlier chunk. However, a
// cross-chunk goog.requireType is allowed to match a goog.provide in a later chunk.
// TODO(b/142571318): move this into CheckClosureImports
if (module != providedModule
&& !moduleGraph.dependsOn(module, providedModule)
&& !method.equals("requireType")) {
compiler.report(
JSError.make(
n,
ProcessClosurePrimitives.XMODULE_REQUIRE_ERROR,
ns,
providedModule.getName(),
module.getName()));
}
}
}
maybeAddNameToSymbolTable(left);
maybeAddNameToSymbolTable(arg);
// Requires should be removed before further processing.
// Some clients run closure pass multiple times, first with
// the checks for broken requires turned off. In these cases, we
// allow broken requires to be preserved by the first run to
// let them be caught in the subsequent run.
if (!preserveGoogProvidesAndRequires && (provided != null || requiresLevel.isOn())) {
requiresToBeRemoved.add(parent);
}
}
}
/** Handles a goog.module that is a legacy namespace. */
private void processLegacyModuleCall(String namespace, Node googModuleCall, JSModule module) {
registerAnyProvidedPrefixes(namespace, googModuleCall, module);
providedNames.put(
namespace,
new ProvidedName(
namespace,
googModuleCall,
module,
/* explicit= */ true,
/* fromPreviousProvide= */ false));
}
/** Handles a goog.provide call. */
private void processProvideCall(NodeTraversal t, Node n, Node parent) {
checkState(n.isCall());
Node left = n.getFirstChild();
Node arg = left.getNext();
if (verifyProvide(left, arg)) {
String ns = arg.getString();
maybeAddNameToSymbolTable(left);
maybeAddNameToSymbolTable(arg);
if (providedNames.containsKey(ns)) {
ProvidedName previouslyProvided = providedNames.get(ns);
if (!previouslyProvided.isExplicitlyProvided() || previouslyProvided.isPreviouslyProvided) {
previouslyProvided.addProvide(parent, t.getModule(), true);
}
} else {
registerAnyProvidedPrefixes(ns, parent, t.getModule());
providedNames.put(
ns,
new ProvidedName(
ns, parent, t.getModule(), /* explicit= */ true, /* fromPreviousProvide= */ false));
}
}
}
/**
* Handles a stub definition for a goog.provided name (e.g. a @typedef or a definition from
* externs)
*
* @param n EXPR_RESULT node.
*/
private void handleStubDefinition(NodeTraversal t, Node n) {
if (!t.inGlobalHoistScope()) {
return;
}
JSDocInfo info = n.getFirstChild().getJSDocInfo();
boolean hasStubDefinition = info != null && (n.isFromExterns() || info.hasTypedefType());
if (hasStubDefinition) {
if (n.getFirstChild().isQualifiedName()) {
String name = n.getFirstChild().getQualifiedName();
ProvidedName pn = providedNames.get(name);
if (pn != null) {
n.putBooleanProp(Node.WAS_PREVIOUSLY_PROVIDED, true);
pn.addDefinition(n, t.getModule());
} else if (n.getBooleanProp(Node.WAS_PREVIOUSLY_PROVIDED)) {
// We didn't find it in the providedNames, but it was previously marked as provided.
// This implies we're in hotswap pass and the current typedef is a provided namespace.
ProvidedName provided = new ProvidedName(name, n, t.getModule(), true, true);
providedNames.put(name, provided);
provided.addDefinition(n, t.getModule());
}
}
}
}
/** Handles a candidate definition for a goog.provided name. */
private void handleCandidateProvideDefinition(NodeTraversal t, Node n, Node parent) {
if (t.inGlobalHoistScope()) {
String name = null;
if (n.isName() && NodeUtil.isNameDeclaration(parent)) {
name = n.getString();
} else if (n.isAssign() && parent.isExprResult()) {
name = n.getFirstChild().getQualifiedName();
}
if (name != null) {
if (parent.getBooleanProp(Node.IS_NAMESPACE)) {
// TODO(b/128361464): stop including goog.module exports in this case.
processProvideFromPreviousPass(t, name, parent);
} else {
ProvidedName pn = providedNames.get(name);
if (pn != null) {
pn.addDefinition(parent, t.getModule());
}
}
}
}
}
/**
* Removes duplicate initializations of goog.provided namespaces created by previous passes
*
*
Should be called after calling {@link ProvidedName#replace()} on all provided names..
*/
private void deleteNamespaceInitializationsFromPreviousProvides() {
for (Node name : previouslyProvidedDefinitions) {
name.detach();
}
}
/**
* Processes the output of processed-provide from a previous pass. This will update our data
* structures in the same manner as if the provide had been processed in this pass.
*
*
TODO(b/128120127): delete this method
*/
private void processProvideFromPreviousPass(NodeTraversal t, String name, Node parent) {
JSModule module = t.getModule();
if (providedNames.containsKey(name)) {
ProvidedName provided = providedNames.get(name);
provided.addDefinition(parent, module);
if (isNamespacePlaceholder(parent)) {
// Remove this later if it is a simple object literal. Replacing the corresponding
// ProvidedName will create a new definition.
// Don't add this as a 'definition' of the provided name to support pushing provides
// into earlier modules.
previouslyProvidedDefinitions.add(parent);
}
} else {
// Record this provide created on a previous pass. This can happen if the previous pass had
// goog.provide('foo.bar');, but all we have now is the rewritten `foo.bar = {};`.
registerAnyProvidedPrefixes(name, parent, module);
ProvidedName provided = new ProvidedName(name, parent, module, true, true);
providedNames.put(name, provided);
provided.addDefinition(parent, module);
}
}
/**
* Verifies that a provide method call has exactly one argument, and that it's a string literal
* and that the contents of the string are valid JS tokens. Reports a compile error if it doesn't.
*
* @return Whether the argument checked out okay
*/
private boolean verifyProvide(Node methodName, Node arg) {
if (!verifyLastArgumentIsString(methodName, arg)) {
return false;
}
if (!NodeUtil.isValidQualifiedName(
compiler.getOptions().getLanguageIn().toFeatureSet(), arg.getString())) {
compiler.report(
JSError.make(
arg,
ProcessClosurePrimitives.INVALID_PROVIDE_ERROR,
arg.getString(),
compiler.getOptions().getLanguageIn().toString()));
return false;
}
return true;
}
/** Marks a goog.forwardDeclare call for removal. */
private void processForwardDeclare(Node n, Node parent) {
CodingConvention convention = compiler.getCodingConvention();
List typeDeclarations = convention.identifyTypeDeclarationCall(n);
if (typeDeclarations != null && typeDeclarations.size() == 1) {
// Forward declaration was recorded and we can remove the call.
Node toRemove = parent.isExprResult() ? parent : parent.getParent();
forwardDeclaresToRemove.add(toRemove);
}
}
/**
* Verifies that a method call has exactly one argument, and that it's a string literal. Reports a
* compile error if it doesn't.
*
* @return Whether the argument checked out okay
*/
private boolean verifyLastArgumentIsString(Node methodName, Node arg) {
return verifyNotNull(methodName, arg)
&& verifyOfType(methodName, arg, Token.STRING)
&& verifyIsLast(methodName, arg);
}
/** @return Whether the argument checked out okay */
private boolean verifyNotNull(Node methodName, Node arg) {
if (arg == null) {
compiler.report(
JSError.make(
methodName,
ProcessClosurePrimitives.NULL_ARGUMENT_ERROR,
methodName.getQualifiedName()));
return false;
}
return true;
}
/** @return Whether the argument checked out okay */
private boolean verifyOfType(Node methodName, Node arg, Token desiredType) {
if (arg.getToken() != desiredType) {
compiler.report(
JSError.make(
methodName,
ProcessClosurePrimitives.INVALID_ARGUMENT_ERROR,
methodName.getQualifiedName()));
return false;
}
return true;
}
/** @return Whether the argument checked out okay */
private boolean verifyIsLast(Node methodName, Node arg) {
if (arg.getNext() != null) {
compiler.report(
JSError.make(
methodName,
ProcessClosurePrimitives.TOO_MANY_ARGUMENTS_ERROR,
methodName.getQualifiedName()));
return false;
}
return true;
}
/**
* Registers ProvidedNames for prefix namespaces if they haven't already been defined. The prefix
* namespaces must be registered in order from shortest to longest.
*
* @param ns The namespace whose prefixes may need to be provided.
* @param node The EXPR of the provide call.
* @param module The current module.
*/
private void registerAnyProvidedPrefixes(String ns, Node node, JSModule module) {
int pos = ns.indexOf('.');
while (pos != -1) {
String prefixNs = ns.substring(0, pos);
pos = ns.indexOf('.', pos + 1);
if (providedNames.containsKey(prefixNs)) {
providedNames.get(prefixNs).addProvide(node, module, /* explicit= */ false);
} else {
providedNames.put(
prefixNs,
new ProvidedName(
prefixNs, node, module, /* explicit= */ false, /* fromPreviousProvide= */ false));
}
}
}
// -------------------------------------------------------------------------
/**
* Stores information about a Closure namespace created by a goog.provide
*
* There are three ways that we find these namespaces in the AST:
*
*
* - An explicit goog.provide. `goog.provide('a.b.c');` creates a ProvidedName for 'a.b.c'.
*
- An implicit parent namespace. `goog.provide('a.b.c');` creates a ProvidedName for 'a.b'.
*
- A provide definition processed by an earlier run. `a.b.c = {};` when annotated
* IS_NAMESPACE
*
*/
class ProvidedName {
// The Closure namespace this name represents, e.g. `a.b` for `goog.provide('a.b');`
private final String namespace;
// The first node in the AST that creates this ProvidedName.
// This is always a goog.provide('a.b'), null (for implicit namespaces and 'goog'), or an
// assignment or declaration for a 'previously provided' name or parent namespace of such.
// This should only be used for source info and a place to hang namespace definitions.
private final Node firstNode;
// The module where this namespace was first goog.provided, if modules exist. */
private final JSModule firstModule;
// The node where the call was explicitly goog.provided. Null if the namespace is implicit.
// If this is previously provided, this will instead be the expression or declaration marked
// as IS_NAMESPACE.
private Node explicitNode = null;
// The JSModule of explicitNode, null if this is not explicit or there are no input modules.
private JSModule explicitModule = null;
// Whether there are child namespaces of this one.
private boolean hasAChildNamespace = false;
// The candidate definition for this namespace. For example, given
// goog.provide('a.b');
// /** @constructor * /
// a.b = function() {};
// the 'candidate definition' of 'a.b' is the GETPROP 'a.b' from the constructor declaration.
private Node candidateDefinition = null;
// The minimum module where the provide namespace definition must appear. If child namespaces of
// this provide appear in multiple modules, this module must be earlier than all child
// namespace's modules.
private JSModule minimumModule = null;
// The replacement declaration. Null until replace() has been called.
private Node replacementNode = null;
// Whether this comes not from a goog.provide, but from a leftover rewritten goog.provide from a
// previous pass run. Implies this is during a hotswap pass.
private final boolean isPreviouslyProvided;
/**
* Initializes a ProvidedName with some basic information, potentially to be updated later.
*
* @param node Can be null (for GOOG or an implicit name), an EXPR_RESULT for a goog.provide, or
* an EXPR_RESULT or name declaration for a previously provided name.
* @param explicit Whether this came from an actual goog.provide('a.b.c'); call
* @param fromPreviousProvide Whether this came from a namespace created by a previous iteration
*/
ProvidedName(
String namespace,
Node node,
JSModule module,
boolean explicit,
boolean fromPreviousProvide) {
Preconditions.checkArgument(
node == null
|| NodeUtil.isExprCall(node)
|| ((fromPreviousProvide || !explicit)
&& (NodeUtil.isExprAssign(node)
|| NodeUtil.isNameDeclaration(node)
|| node.isExprResult() && node.getFirstChild().isQualifiedName())),
node);
this.namespace = namespace;
this.firstNode = node;
this.firstModule = module;
this.isPreviouslyProvided = fromPreviousProvide;
addProvide(node, module, explicit);
}
/**
* Adds an implicit or explicit provide.
*
* Every provided name can have multiple implicit provides but a maximum of one explicit
* provide.
*
*
We may also consider a namespace definition leftover from a previous pass to be a
* 'provide' if in hotswap mode.
*
* @param node the EXPR_RESULT representing this provide or possible a VAR for a previously
* provided name. null if implicit.
*/
void addProvide(Node node, JSModule module, boolean explicit) {
if (explicit) {
// goog.provide('name.space');
checkState(explicitNode == null || isPreviouslyProvided);
checkArgument(
node.isExprResult() || (NodeUtil.isNameDeclaration(node) && isPreviouslyProvided),
node);
explicitNode = node;
explicitModule = module;
} else {
// goog.provide('name.space.some.child');
hasAChildNamespace = true;
}
updateMinimumModule(module);
}
/** Whether there existed a `goog.provide('a.b');` for this name 'a.b' */
boolean isExplicitlyProvided() {
return explicitNode != null;
}
boolean isFromExterns() {
return explicitNode.isFromExterns();
}
private boolean hasCandidateDefinitionNotFromPreviousPass() {
// Exclude 'candidate definitions' that were added by previous pass runs because when
// rewriting provides, we can erase definitions that the compiler itself added, but not
// definitions that a user added.
return candidateDefinition != null
&& !previouslyProvidedDefinitions.contains(candidateDefinition);
}
/**
* Returns the `goog.provide` or legacy namespace `goog.module` call that created this name, if
* any, or otherwise the first 'previous provide' assignment that created this name.
*/
Node getFirstProvideCall() {
return firstNode;
}
/**
* Returns the definition of this provided namespace in the input code, if any, or null.
*
*
For example, this returns `a.b = class {};` given 'a.b' in
*
*
* goog.provide('a.b');
* a.b = class {};
*
*
* Note: this method will only return candidate definitions that count towards provide
* rewriting. If a name is defined, then provided, the candidate definition will not be the
* early definition. This doesn't completely mimic uncompiled behavior, but supports some legacy
* code. Externs definitions never count.
*/
Node getCandidateDefinition() {
return candidateDefinition;
}
/** Returns the Closure namespace of this provide, e.g. "a.b" for `goog.provide('a.b');` */
String getNamespace() {
return namespace;
}
/**
* Records function declaration, variable declarations, and assignments that refer to this
* provided namespace.
*
* This pass gives preference to declarations. If no declaration exists, records a reference
* to an assignment so it can be repurposed later into a declaration.
*/
private void addDefinition(Node node, JSModule module) {
Preconditions.checkArgument(
node.isExprResult() // assign
|| node.isFunction()
|| NodeUtil.isNameDeclaration(node));
checkArgument(explicitNode != node || isPreviouslyProvided);
if ((candidateDefinition == null) || !node.isExprResult()) {
candidateDefinition = node;
updateMinimumModule(module);
}
}
private void updateMinimumModule(JSModule newModule) {
if (minimumModule == null) {
minimumModule = newModule;
} else if (moduleGraph.getModuleCount() > 1) {
minimumModule = moduleGraph.getDeepestCommonDependencyInclusive(minimumModule, newModule);
} else {
// If there is no module graph, then there must be exactly one
// module in the program.
checkState(newModule == minimumModule, "Missing module graph");
}
}
/**
* Replace the provide statement.
*
*
If we're providing a name with no definition, then create one. If we're providing a name
* with a duplicate definition, then make sure that definition becomes a declaration.
*/
private void replace() {
if (firstNode == null) {
// Don't touch the base case ('goog').
replacementNode = candidateDefinition;
return;
}
// Handle the case where there is a duplicate definition for an explicitly
// provided symbol.
if (hasCandidateDefinitionNotFromPreviousPass() && explicitNode != null) {
JSDocInfo info;
if (candidateDefinition.isExprResult()) {
info = candidateDefinition.getFirstChild().getJSDocInfo();
} else {
info = candidateDefinition.getJSDocInfo();
}
// Validate that the namespace is not declared as a generic object type.
if (info != null) {
JSTypeExpression expr = info.getType();
if (expr != null) {
Node n = expr.getRoot();
if (n.getToken() == Token.BANG) {
n = n.getFirstChild();
}
if (n.isString()
&& !n.hasChildren() // templated object types are ok.
&& n.getString().equals("Object")) {
compiler.report(
JSError.make(candidateDefinition, ProcessClosurePrimitives.WEAK_NAMESPACE_TYPE));
}
}
}
// Does this need a VAR keyword?
replacementNode = candidateDefinition;
if (candidateDefinition.isExprResult()) {
Node exprNode = candidateDefinition.getOnlyChild();
if (exprNode.isAssign()) {
Node nameNode = exprNode.getFirstChild();
if (nameNode.isName()) {
// In the case of a simple name, `name = value;`, we need to ensure the name is
// actually declared with `var`.
convertProvideAssignmentToVarDeclaration(exprNode, nameNode);
} else {
// `some.provided.namespace = value;`
// We don't need to change the definition, but mark it as 'IS_NAMESPACE' so that
// future passes know this was originally provided.
candidateDefinition.putBooleanProp(Node.IS_NAMESPACE, true);
}
} else {
// /** @typedef {something} */ name.space.Type;
checkState(exprNode.isQualifiedName(), exprNode);
// If this namespace has child namespaces, we still need to add an object to hang them
// on to avoid creating broken code.
// We must cast the type of the literal to unknown, because the type checker doesn't
// expect the namespace to have a value.
if (hasAChildNamespace) {
createNamespaceInitialization(
createDeclarationNode(
astFactory.createCastToUnknown(
astFactory.createObjectLit(), createUnknownTypeJsDocInfo(exprNode))));
}
}
}
} else {
// Handle the case where there's not an existing definition.
createNamespaceInitialization(createDeclarationNode(astFactory.createObjectLit()));
}
// Remove the `goog.provide('a.b.c');` call.
if (explicitNode != null && !isPreviouslyProvided) {
if (preserveGoogProvidesAndRequires) {
return;
}
compiler.reportChangeToEnclosingScope(explicitNode);
explicitNode.detach();
}
}
private void convertProvideAssignmentToVarDeclaration(Node assignNode, Node nameNode) {
// Convert `providedName = value;` into `var providedName = value;`.
checkArgument(assignNode.isAssign(), assignNode);
checkArgument(nameNode.isName(), nameNode);
Node valueNode = nameNode.getNext();
assignNode.removeChild(nameNode);
assignNode.removeChild(valueNode);
Node varNode = IR.var(nameNode, valueNode).useSourceInfoFrom(candidateDefinition);
varNode.setJSDocInfo(assignNode.getJSDocInfo());
varNode.putBooleanProp(Node.IS_NAMESPACE, true);
candidateDefinition.replaceWith(varNode);
replacementNode = varNode;
compiler.reportChangeToEnclosingScope(varNode);
}
/** Adds an assignment or declaration to this namespace to the AST, using the provided value */
private void createNamespaceInitialization(Node replacement) {
replacementNode = replacement;
if (firstModule == minimumModule) {
firstNode.getParent().addChildBefore(replacementNode, firstNode);
} else {
// In this case, the name was implicitly provided by two independent
// modules. We need to move this code up to a common module.
int indexOfDot = namespace.lastIndexOf('.');
if (indexOfDot == -1) {
// Any old place is fine.
compiler.getNodeForCodeInsertion(minimumModule).addChildToBack(replacementNode);
} else {
// Add it after the parent namespace.
ProvidedName parentName = providedNames.get(namespace.substring(0, indexOfDot));
checkNotNull(parentName);
checkNotNull(parentName.replacementNode);
parentName
.replacementNode
.getParent()
.addChildAfter(replacementNode, parentName.replacementNode);
}
}
compiler.reportChangeToEnclosingScope(replacementNode);
}
/**
* Create the declaration node for this name, without inserting it into the AST.
*
* @param value the object literal namespace, possibly in a CAST
*/
private Node createDeclarationNode(Node value) {
checkArgument(value.isObjectLit() || value.isCast(), value);
if (namespace.indexOf('.') == -1) {
return makeVarDeclNode(value);
} else {
return makeAssignmentExprNode(value);
}
}
/** Creates a simple namespace variable declaration (e.g. var foo = {};). */
private Node makeVarDeclNode(Node value) {
Node name = IR.name(namespace);
name.addChildToFront(value);
if (globalTypedScope != null) {
TypedVar typedVar = checkNotNull(globalTypedScope.getVar(namespace), namespace);
name.setJSType(typedVar.getType());
}
Node decl = IR.var(name);
decl.putBooleanProp(Node.IS_NAMESPACE, true);
if (compiler.getCodingConvention().isConstant(namespace)) {
name.putBooleanProp(Node.IS_CONSTANT_NAME, true);
}
if (!hasCandidateDefinitionNotFromPreviousPass()) {
decl.setJSDocInfo(NodeUtil.createConstantJsDoc());
}
checkState(isNamespacePlaceholder(decl));
setSourceInfo(decl);
return decl;
}
/** Creates a dotted namespace assignment expression (e.g. foo.bar = {};). */
private Node makeAssignmentExprNode(Node value) {
Node lhs = astFactory.createQName(globalTypedScope, namespace).srcrefTree(firstNode);
Node decl = IR.exprResult(astFactory.createAssign(lhs, value));
decl.putBooleanProp(Node.IS_NAMESPACE, true);
if (!hasCandidateDefinitionNotFromPreviousPass()) {
decl.getFirstChild().setJSDocInfo(NodeUtil.createConstantJsDoc());
}
checkState(isNamespacePlaceholder(decl));
setSourceInfo(decl);
// This function introduces artifical nodes and we don't need them for indexing.
// Marking all but the last one as non-indexable. So if this function adds:
// foo.bar.baz = {};
// then we mark foo and bar as non-indexable.
lhs.getFirstChild().makeNonIndexableRecursive();
return decl;
}
/** Copy source info to the new node. */
private void setSourceInfo(Node newNode) {
Node provideStringNode = getProvideStringNode();
int offset = provideStringNode == null ? 0 : getSourceInfoOffset();
Node sourceInfoNode = provideStringNode == null ? firstNode : provideStringNode;
newNode.useSourceInfoIfMissingFromForTree(sourceInfoNode);
if (offset != 0) {
newNode.setSourceEncodedPositionForTree(sourceInfoNode.getSourcePosition() + offset);
// Given namespace "foo.bar.baz" we create node for "baz" here and need to calculate
// length of the last component which is "baz".
int lengthOfLastComponent = namespace.length() - (namespace.lastIndexOf(".") + 1);
newNode.setLengthForTree(lengthOfLastComponent);
}
}
/** Get the offset into the provide node where the symbol appears. */
private int getSourceInfoOffset() {
int indexOfLastDot = namespace.lastIndexOf('.');
// +1 for the opening quote
// +1 for the dot
// if there's no dot, then the -1 index cancels it out
// so elegant!
return 2 + indexOfLastDot;
}
private Node getProvideStringNode() {
return (firstNode.hasChildren() && NodeUtil.isExprCall(firstNode))
? firstNode.getFirstChild().getLastChild()
: null;
}
@Override
@GwtIncompatible("Unnecessary") // This is just for debugging in an IDE.
public String toString() {
String explicitOrImplicit = isExplicitlyProvided() ? "explicit" : "implicit";
return String.format("ProvidedName: %s, %s", namespace, explicitOrImplicit);
}
}
private JSDocInfo createUnknownTypeJsDocInfo(Node sourceNode) {
JSDocInfoBuilder castToUnknownBuilder = new JSDocInfoBuilder(true);
castToUnknownBuilder.recordType(
new JSTypeExpression(
new Node(Token.QMARK).srcref(sourceNode), ""));
return castToUnknownBuilder.build();
}
/**
* Returns whether the node initializes a goog.provide'd namespace (e.g. `a.b = {};`) with a
* simple namespace object literal (e.g. not `a.b = class {}`;)
*/
private static boolean isNamespacePlaceholder(Node n) {
if (!n.getBooleanProp(Node.IS_NAMESPACE)) {
return false;
}
Node value = null;
if (n.isExprResult()) {
Node assign = n.getFirstChild();
value = assign.getLastChild();
} else if (n.isVar()) {
Node name = n.getFirstChild();
value = name.getFirstChild();
}
if (value == null) {
return false;
}
if (value.isCast()) {
// There may be a cast to unknown type wrapped around the value.
value = value.getOnlyChild();
}
return value.isObjectLit() && !value.hasChildren();
}
/** Add the given qualified name node to the symbol table. */
private void maybeAddNameToSymbolTable(Node name) {
if (preprocessorSymbolTable != null) {
preprocessorSymbolTable.addReference(name);
}
}
}