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/*
* Copyright 2014 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.common.collect.ImmutableList.toImmutableList;
import static com.google.javascript.jscomp.AstFactory.type;
import static com.google.javascript.jscomp.ClosurePrimitiveErrors.INVALID_FORWARD_DECLARE_NAMESPACE;
import static com.google.javascript.jscomp.ClosurePrimitiveErrors.INVALID_GET_NAMESPACE;
import static com.google.javascript.jscomp.ClosurePrimitiveErrors.INVALID_REQUIRE_DYNAMIC;
import static com.google.javascript.jscomp.ClosurePrimitiveErrors.INVALID_REQUIRE_NAMESPACE;
import static com.google.javascript.jscomp.ClosurePrimitiveErrors.INVALID_REQUIRE_TYPE_NAMESPACE;
import com.google.common.base.MoreObjects;
import com.google.common.base.Strings;
import com.google.common.collect.HashMultimap;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Multimap;
import com.google.common.collect.Sets;
import com.google.javascript.jscomp.CompilerOptions.LanguageMode;
import com.google.javascript.jscomp.parsing.parser.FeatureSet.Feature;
import com.google.javascript.rhino.IR;
import com.google.javascript.rhino.JSDocInfo;
import com.google.javascript.rhino.Node;
import com.google.javascript.rhino.Token;
import com.google.javascript.rhino.jstype.JSType;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Deque;
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 org.jspecify.nullness.Nullable;
/**
* Process aliases in goog.modules.
*
*
* goog.module('foo.Bar');
* var Baz = goog.require('foo.Baz');
* class Bar extends Baz {}
* exports = Bar;
*
*
* becomes
*
*
* class module$contents$foo$Bar_Bar extends module$exports$foo$Baz {}
* var module$exports$foo$Bar = module$contents$foo$Bar_Bar;
*
*
* and
*
*
* goog.loadModule(function(exports) {
* goog.module('foo.Bar');
* var Baz = goog.require('foo.Baz');
* class Bar extends Baz {}
* exports = Bar;
* return exports;
* })
*
*
* becomes
*
*
* class module$contents$foo$Bar_Bar extends module$exports$foo$Baz {}
* var module$exports$foo$Bar = module$contents$foo$Bar_Bar;
*
*/
final class ClosureRewriteModule implements CompilerPass {
static final DiagnosticType INVALID_MODULE_ID_ARG =
DiagnosticType.error(
"JSC_GOOG_MODULE_INVALID_MODULE_ID_ARG",
"goog.module parameter must be a string literal");
static final DiagnosticType INVALID_PROVIDE_NAMESPACE =
DiagnosticType.error(
"JSC_GOOG_MODULE_INVALID_PROVIDE_NAMESPACE",
"goog.provide parameter must be a string literal.");
static final DiagnosticType INVALID_PROVIDE_CALL =
DiagnosticType.error(
"JSC_GOOG_MODULE_INVALID_PROVIDE_CALL", "goog.provide can not be called in goog.module.");
static final DiagnosticType INVALID_GET_ALIAS =
DiagnosticType.error(
"JSC_GOOG_MODULE_INVALID_GET_ALIAS", "goog.module.get should not be aliased.");
static final DiagnosticType INVALID_EXPORT_COMPUTED_PROPERTY =
DiagnosticType.error(
"JSC_GOOG_MODULE_INVALID_EXPORT_COMPUTED_PROPERTY",
"Computed properties are not yet supported in goog.module exports.");
static final DiagnosticType USELESS_USE_STRICT_DIRECTIVE =
DiagnosticType.disabled(
"JSC_USELESS_USE_STRICT_DIRECTIVE", "'use strict' is unnecessary in goog.module files.");
static final DiagnosticType IMPORT_INLINING_SHADOWS_VAR =
DiagnosticType.error(
"JSC_IMPORT_INLINING_SHADOWS_VAR",
"Inlining of reference to import \"{1}\" shadows var \"{0}\".");
static final DiagnosticType ILLEGAL_DESTRUCTURING_DEFAULT_EXPORT =
DiagnosticType.error(
"JSC_ILLEGAL_DESTRUCTURING_DEFAULT_EXPORT",
"Destructuring import only allowed for importing module with named exports.\n"
+ "See https://github.com/google/closure-compiler/wiki/goog.module-style");
static final DiagnosticType ILLEGAL_DESTRUCTURING_NOT_EXPORTED =
DiagnosticType.error(
"JSC_ILLEGAL_DESTRUCTURING_NOT_EXPORTED",
"Destructuring import reference to name \"{0}\" was not exported in module {1}");
static final DiagnosticType LOAD_MODULE_FN_MISSING_RETURN =
DiagnosticType.error(
"JSC_LOAD_MODULE_FN_MISSING_RETURN",
"goog.loadModule function should end with 'return exports;'");
static final DiagnosticType ILLEGAL_MODULE_RENAMING_CONFLICT =
DiagnosticType.error(
"JSC_ILLEGAL_MODULE_RENAMING_CONFLICT",
"Internal compiler error: rewritten module global name {0} is already in use.");
private static final String MODULE_EXPORTS_PREFIX = "module$exports$";
private static final String MODULE_CONTENTS_PREFIX = "module$contents$";
// Prebuilt Nodes to speed up Node.matchesQualifiedName() calls
private static final Node GOOG_FORWARDDECLARE = IR.getprop(IR.name("goog"), "forwardDeclare");
private static final Node GOOG_LOADMODULE = IR.getprop(IR.name("goog"), "loadModule");
private static final Node GOOG_MODULE = IR.getprop(IR.name("goog"), "module");
private static final Node GOOG_MODULE_DECLARELEGACYNAMESPACE =
IR.getprop(GOOG_MODULE, "declareLegacyNamespace");
private static final Node GOOG_MODULE_GET = IR.getprop(GOOG_MODULE.cloneTree(), "get");
private static final Node GOOG_PROVIDE = IR.getprop(IR.name("goog"), "provide");
private static final Node GOOG_REQUIRE = IR.getprop(IR.name("goog"), "require");
private static final Node GOOG_REQUIRETYPE = IR.getprop(IR.name("goog"), "requireType");
private static final Node GOOG_REQUIREDYNAMIC = IR.getprop(IR.name("goog"), "requireDynamic");
private static final String GOOG_REQUIREDYNAMIC_NAME = "goog.requireDynamic";
private static final String IMPORT_HANDLER_NAME = "importHandler_";
private final AbstractCompiler compiler;
private final AstFactory astFactory;
private final PreprocessorSymbolTable preprocessorSymbolTable;
private final boolean preserveSugar;
private final LinkedHashMap syntheticExterns = new LinkedHashMap<>();
private @Nullable Scope globalScope =
null; // non-final because it must be set after process() is called
/** Indicates where new nodes should be added in relation to some other node. */
private static enum AddAt {
BEFORE,
AFTER
}
private static enum ScopeType {
EXEC_CONTEXT,
BLOCK
}
/**
* Describes the context of an "unrecognized require" scenario so that it will be possible to
* categorize and report it as either a "not provided yet" or "not provided at all" error at the
* end.
*/
private static final class UnrecognizedRequire {
// A goog.require() call, or a goog.module.get() call.
final Node requireNode;
final String namespaceId;
UnrecognizedRequire(Node requireNode, String namespaceId, boolean mustBeOrdered) {
this.requireNode = requireNode;
this.namespaceId = namespaceId;
}
}
private static final class ExportDefinition {
// Null if the export is a default export (exports = expr)
@Nullable String exportName;
// Null if the export is of a @typedef
@Nullable Node rhs;
// Null if the export is of anything other than a name
@Nullable Var nameDecl;
@Override
public String toString() {
return MoreObjects.toStringHelper(this)
.add("exportName", exportName)
.add("rhs", rhs)
.add("nameDecl", nameDecl)
.omitNullValues()
.toString();
}
private static final ImmutableSet INLINABLE_NAME_PARENTS =
Sets.immutableEnumSet(Token.VAR, Token.CONST, Token.LET, Token.FUNCTION, Token.CLASS);
static ExportDefinition newDefaultExport(NodeTraversal t, Node rhs) {
return newNamedExport(t, null, rhs);
}
static ExportDefinition newNamedExport(NodeTraversal t, @Nullable String name, Node rhs) {
ExportDefinition newExport = new ExportDefinition();
newExport.exportName = name;
newExport.rhs = rhs;
if (rhs != null && (rhs.isName() || rhs.isStringKey())) {
newExport.nameDecl = t.getScope().getVar(rhs.getString());
}
return newExport;
}
String getExportPostfix() {
if (exportName == null) {
return "";
}
return "." + exportName;
}
boolean hasInlinableName(Set exportedNames) {
if (nameDecl == null
|| exportedNames.contains(nameDecl)
|| !INLINABLE_NAME_PARENTS.contains(nameDecl.getParentNode().getToken())
|| NodeUtil.isFunctionDeclaration(nameDecl.getParentNode())) {
return false;
}
Node initialValue = nameDecl.getInitialValue();
if (initialValue == null || !initialValue.isCall()) {
return true;
}
Node method = initialValue.getFirstChild();
if (!method.isGetProp()) {
return true;
}
Node maybeGoog = method.getFirstChild();
if (!maybeGoog.isName() || !maybeGoog.getString().equals("goog")) {
return true;
}
String name = method.getString();
return !name.equals("require") && !name.equals("forwardDeclare") && !name.equals("getMsg");
}
@Nullable String getLocalName() {
return nameDecl != null ? nameDecl.getName() : null;
}
}
private static class AliasName {
final String newName;
final @Nullable String namespaceId; // non-null only if this is an alias of a module itself
AliasName(String newName, @Nullable String namespaceId) {
this.newName = newName;
this.namespaceId = namespaceId;
}
}
private static final class ScriptDescription {
boolean isModule;
boolean declareLegacyNamespace;
String namespaceId; // "a.b.c"
String contentsPrefix; // "module$contents$a$b$c_
final Set topLevelNames = new HashSet<>(); // For prefixed content renaming.
final Deque childScripts = new ArrayDeque<>();
final Map namesToInlineByAlias = new HashMap<>(); // For alias inlining.
/** Transient state. */
boolean willCreateExportsObject;
boolean hasCreatedExportObject;
ExportDefinition defaultExport;
@Nullable String defaultExportLocalName;
final Set namedExports = new HashSet<>();
final Map exportsToInline = new HashMap<>();
// The root of the module. The MODULE_BODY node that contains the module contents.
// For recognizing top level names.
Node rootNode;
public void addChildScript(ScriptDescription childScript) {
childScripts.addLast(childScript);
}
public ScriptDescription removeFirstChildScript() {
return childScripts.removeFirst();
}
// "module$exports$a$b$c" for non-legacy modules
@Nullable String getBinaryNamespace() {
if (!this.isModule || this.declareLegacyNamespace) {
return null;
}
return getBinaryModuleNamespace(namespaceId);
}
@Nullable String getExportedNamespace() {
if (this.declareLegacyNamespace) {
return this.namespaceId;
}
return this.getBinaryNamespace();
}
}
static String getBinaryModuleNamespace(String namespaceId) {
return MODULE_EXPORTS_PREFIX + namespaceId.replace('.', '$');
}
private class ScriptPreprocessor extends NodeTraversal.AbstractPreOrderCallback {
@Override
public boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
case ROOT:
case MODULE_BODY:
return true;
case SCRIPT:
if (NodeUtil.isGoogModuleFile(n)) {
checkAndSetStrictModeDirective(t, n);
}
return true;
case NAME:
preprocessExportDeclaration(t, n);
return true;
default:
// Don't traverse into non-module scripts.
return !parent.isScript();
}
}
}
private class ScriptRecorder implements NodeTraversal.Callback {
@Override
public boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
case MODULE_BODY:
recordModuleBody(n);
break;
case CALL:
Node method = n.getFirstChild();
if (!method.isGetProp()) {
break;
}
if (method.matchesQualifiedName(GOOG_MODULE)) {
recordGoogModule(t, n);
} else if (method.matchesQualifiedName(GOOG_MODULE_DECLARELEGACYNAMESPACE)) {
recordGoogDeclareLegacyNamespace();
} else if (method.matchesQualifiedName(GOOG_PROVIDE)) {
recordGoogProvide(t, n);
} else if (method.matchesQualifiedName(GOOG_REQUIRE)) {
recordGoogRequire(t, n, /* mustBeOrdered= */ true);
} else if (method.matchesQualifiedName(GOOG_REQUIRETYPE)) {
recordGoogRequireType(t, n);
} else if (method.matchesQualifiedName(GOOG_REQUIREDYNAMIC)) {
recordGoogRequireDynamic(t, n);
} else if (method.matchesQualifiedName(GOOG_FORWARDDECLARE) && !parent.isExprResult()) {
recordGoogForwardDeclare(t, n);
} else if (method.matchesQualifiedName(GOOG_MODULE_GET)) {
recordGoogModuleGet(t, n);
}
break;
case CLASS:
case FUNCTION:
if (isTopLevel(t, n, ScopeType.BLOCK)) {
recordTopLevelClassOrFunctionName(n);
}
break;
case CONST:
case LET:
case VAR:
if (isTopLevel(t, n, n.isVar() ? ScopeType.EXEC_CONTEXT : ScopeType.BLOCK)) {
recordTopLevelVarNames(n);
}
break;
case GETPROP:
if (isExportPropertyAssignment(t, n)) {
recordExportsPropertyAssignment(t, n);
}
break;
case NAME:
maybeRecordExportDeclaration(t, n);
break;
default:
break;
}
return true;
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if (n.isModuleBody()) {
popScript();
}
}
}
private class ScriptUpdater implements NodeTraversal.Callback {
final Deque scriptDescriptions;
ScriptUpdater(Deque scriptDescriptions) {
this.scriptDescriptions = scriptDescriptions;
}
@Override
public boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
case SCRIPT:
ScriptDescription currentDescription = scriptDescriptions.removeFirst();
checkState(currentDescription.rootNode == n);
if (n.isFromExterns() && !NodeUtil.isFromTypeSummary(n)) {
return false;
}
checkState(scriptStack.isEmpty());
pushScript(currentDescription);
// Capture the scope before doing any rewriting to the scope.
t.getScope();
// Capture the global scope for later reference.
if (globalScope == null) {
globalScope = t.getScope().getGlobalScope();
}
break;
case MODULE_BODY:
if (parent.getBooleanProp(Node.GOOG_MODULE)) {
updateModuleBodyEarly(n);
} else {
return false;
}
break;
case CALL:
Node method = n.getFirstChild();
if (!method.isGetProp()) {
break;
}
if (method.matchesQualifiedName(GOOG_MODULE)) {
updateGoogModule(t, n);
} else if (method.matchesQualifiedName(GOOG_MODULE_DECLARELEGACYNAMESPACE)) {
updateGoogDeclareLegacyNamespace(n);
} else if (method.matchesQualifiedName(GOOG_REQUIRE)
|| method.matchesQualifiedName(GOOG_REQUIRETYPE)) {
updateGoogRequire(t, n);
} else if (method.matchesQualifiedName(GOOG_FORWARDDECLARE) && !parent.isExprResult()) {
updateGoogForwardDeclare(t, n);
}
break;
case GETPROP:
if (isExportPropertyAssignment(t, n)) {
updateExportsPropertyAssignment(n, t);
}
break;
default:
break;
}
if (n.getJSDocInfo() != null) {
rewriteJsdoc(n.getJSDocInfo(), t.getScope());
}
return true;
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
case MODULE_BODY:
updateModuleBody(n);
break;
case NAME:
maybeUpdateTopLevelName(t, n);
maybeUpdateExportDeclaration(t, n);
t.getScope(); // Creating the scope here has load-bearing side-effects.
maybeUpdateExportNameRef(t, n);
break;
case SCRIPT:
checkState(currentScript.rootNode == n);
popScript();
break;
default:
break;
}
}
}
/**
* Rewrites JsDoc type references to match AST changes resulting from imported alias inlining,
* module content renaming of top level constructor functions and classes, and module renaming
* from fully qualified legacy namespace to its binary name.
*/
private void rewriteJsdoc(JSDocInfo info, Scope scope) {
ReplaceJsDocRefs replacer = new ReplaceJsDocRefs(scope);
for (Node typeNode : info.getTypeNodes()) {
NodeUtil.visitPreOrder(typeNode, replacer);
}
}
/**
* Rewrites JsDoc type references to match AST changes resulting from imported alias inlining,
* module content renaming of top level constructor functions and classes, and module renaming
* from fully qualified legacy namespace to its binary name.
*/
private final class ReplaceJsDocRefs implements NodeUtil.Visitor {
private final Scope scope;
ReplaceJsDocRefs(Scope scope) {
this.scope = scope;
}
@Override
public void visit(Node typeRefNode) {
if (!typeRefNode.isStringLit()) {
return;
}
// A type name that might be simple like "Foo" or qualified like "foo.Bar".
final String typeName = typeRefNode.getString();
int dot = typeName.indexOf('.');
String rootOfType = dot == -1 ? typeName : typeName.substring(0, dot);
Var rootVar = this.scope.getVar(rootOfType);
if (rootVar != null
&& !rootVar.getScope().getClosestHoistScope().isGlobal()
&& !rootVar.getScope().isModuleScope()) {
// this is a variable inside a local scope, not a module local or imported alias.
return;
}
// Rewrite the type node if any of the following hold, in priority order:
// - the root of the type name is in our set of aliases to inline
// - the root of the type name is a name defined in the module scope
// - a prefix of the type name matches a Closure namespace
// AND the following is false:
// - the root of the type name is defined in an inner scope
// If the name is an alias for an imported namespace rewrite from
// "{Foo}" to
// "{module$exports$bar$Foo}" or
// "{bar.Foo}"
if (currentScript.namesToInlineByAlias.containsKey(rootOfType)) {
if (preprocessorSymbolTable != null) {
// Jsdoc type node is a single STRING node that spans the whole type. For example
// STRING node "bar.Foo". When rewriting modules potentially replace only "module"
// part of the type: "bar.Foo" => "module$exports$bar$Foo". So we need to remember
// that "bar" as alias. To do that we clone type node and make "bar" node from it.
Node moduleOnlyNode = typeRefNode.cloneNode();
safeSetString(moduleOnlyNode, rootOfType);
moduleOnlyNode.setLength(rootOfType.length());
maybeAddAliasToSymbolTable(moduleOnlyNode, currentScript.namespaceId);
}
String aliasedNamespace = currentScript.namesToInlineByAlias.get(rootOfType).newName;
String remainder = dot == -1 ? "" : typeName.substring(dot);
safeSetString(typeRefNode, aliasedNamespace + remainder);
} else if (currentScript.isModule && currentScript.topLevelNames.contains(rootOfType)) {
// If this is a module and the type name is the name of a top level var/function/class
// defined in this script then that var will have been previously renamed from Foo to
// module$contents$Foo_Foo. Update the JsDoc reference to match.
safeSetString(typeRefNode, currentScript.contentsPrefix + typeName);
} else if (currentScript.isModule && rootOfType.equals("exports")) {
// rewrite a type reference to the implicit "exports" variable
// e.g. /** @type {exports.Foo} */ -> /** @type {module$exports$my$mod.Foo} */
String namespace = currentScript.getBinaryNamespace();
String remainder = dot == -1 ? "" : typeName.substring(dot);
safeSetString(typeRefNode, namespace + remainder);
} else {
rewriteIfClosureNamespaceRef(typeName, typeRefNode);
}
}
/**
* Tries to match the longest possible prefix of this type to a Closure namespace
*
* If the longest prefix match is a legacy module or provide, this is a no-op. If the longest
* prefix match is a non-legacy module, this method rewrites the type node.
*/
private void rewriteIfClosureNamespaceRef(String typeName, Node typeRefNode) {
// Tries to rename progressively shorter type prefixes like "foo.Bar.Baz", then "foo.Bar",
// then "foo".
String prefixTypeName = typeName;
String suffix = "";
while (true) {
String binaryNamespaceIfModule = rewriteState.getBinaryNamespace(prefixTypeName);
if (legacyScriptNamespacesAndPrefixes.contains(prefixTypeName)
&& binaryNamespaceIfModule == null) {
// This thing is definitely coming from a legacy script and so the fully qualified
// type name will always resolve as is.
return;
}
// If the typeName is a reference to a fully qualified legacy namespace like
// "foo.bar.Baz" of something that is actually a module then rewrite the JsDoc reference
// to "module$exports$Bar".
// Note: we may want to ban this pattern in the future. See b/133501660.
if (binaryNamespaceIfModule != null) {
safeSetString(typeRefNode, binaryNamespaceIfModule + suffix);
return;
}
if (prefixTypeName.contains(".")) {
prefixTypeName = prefixTypeName.substring(0, prefixTypeName.lastIndexOf('.'));
suffix = typeName.substring(prefixTypeName.length());
} else {
break;
}
}
}
}
// Per script state needed for rewriting.
private final Deque scriptStack = new ArrayDeque<>();
private @Nullable ScriptDescription currentScript = null;
// Global state tracking an association between the dotted names of goog.module()s and whether
// the goog.module declares itself as a legacy namespace.
// Allows for detecting duplicate goog.module()s and for rewriting fully qualified
// JsDoc type references to goog.module() types in legacy scripts.
private static final class GlobalRewriteState {
private final Map scriptDescriptionsByGoogModuleNamespace =
new HashMap<>();
private final Multimap namespaceIdsByScriptNode = HashMultimap.create();
private final Set providedNamespaces = new HashSet<>();
boolean containsModule(String namespaceId) {
return scriptDescriptionsByGoogModuleNamespace.containsKey(namespaceId);
}
boolean isLegacyModule(String namespaceId) {
checkArgument(containsModule(namespaceId));
return scriptDescriptionsByGoogModuleNamespace.get(namespaceId).declareLegacyNamespace;
}
@Nullable String getBinaryNamespace(String namespaceId) {
ScriptDescription script = scriptDescriptionsByGoogModuleNamespace.get(namespaceId);
return script == null ? null : script.getBinaryNamespace();
}
/** Returns the type of a goog.require of the given goog.module, or null if not a module. */
@Nullable JSType getGoogModuleNamespaceType(String namespaceId) {
ScriptDescription googModule = scriptDescriptionsByGoogModuleNamespace.get(namespaceId);
return googModule == null ? null : googModule.rootNode.getJSType();
}
private @Nullable String getExportedNamespaceOrScript(String namespaceId) {
if (providedNamespaces.contains(namespaceId)) {
return namespaceId;
}
ScriptDescription script = scriptDescriptionsByGoogModuleNamespace.get(namespaceId);
return script == null ? null : script.getExportedNamespace();
}
}
private final GlobalRewriteState rewriteState = new GlobalRewriteState();
// All prefix namespaces from goog.provides and legacy goog.modules.
private final Set legacyScriptNamespacesAndPrefixes = new HashSet<>();
private final List unrecognizedRequires = new ArrayList<>();
private final ArrayList googModuleGetCalls = new ArrayList<>();
private final ArrayList googRequireDynamicCalls = new ArrayList<>();
private final TypedScope globalTypedScope;
ClosureRewriteModule(
AbstractCompiler compiler,
PreprocessorSymbolTable preprocessorSymbolTable,
@Nullable TypedScope globalTypedScope) {
checkArgument(globalTypedScope == null || globalTypedScope.isGlobal());
this.compiler = compiler;
this.astFactory = compiler.createAstFactory();
this.preprocessorSymbolTable = preprocessorSymbolTable;
this.preserveSugar = compiler.getOptions().shouldPreserveGoogModule();
this.globalTypedScope = globalTypedScope;
}
private class UnwrapGoogLoadModule extends NodeTraversal.AbstractPreOrderCallback {
@Override
public boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
case ROOT:
case SCRIPT:
return true;
case EXPR_RESULT:
Node call = n.getFirstChild();
if (NodeUtil.isCallTo(call, GOOG_LOADMODULE) && call.getLastChild().isFunction()) {
parent.putBooleanProp(Node.GOOG_MODULE, true);
Node functionNode = call.getLastChild();
compiler.reportFunctionDeleted(functionNode);
Node moduleBody = functionNode.getLastChild().detach();
moduleBody.setToken(Token.MODULE_BODY);
Node exportsParameter = NodeUtil.getFunctionParameters(functionNode).getOnlyChild();
moduleBody.setJSType(exportsParameter.getJSType());
n.replaceWith(moduleBody);
Node returnNode = moduleBody.getLastChild();
if (!returnNode.isReturn()) {
compiler.report(JSError.make(moduleBody, LOAD_MODULE_FN_MISSING_RETURN));
} else {
returnNode.detach();
}
t.reportCodeChange();
}
return false;
default:
return false;
}
}
}
@Override
public void process(Node externs, Node root) {
// Record all the scripts first so that the googModuleNamespaces global state can be complete
// before doing any updating also queue up scriptDescriptions for later use in ScriptUpdater
// runs.
Deque scriptDescriptions = new ArrayDeque<>();
for (Node parent : ImmutableList.of(externs, root)) {
for (Node script = parent.getFirstChild(); script != null; script = script.getNext()) {
checkState(script.isScript(), script);
NodeTraversal.traverse(compiler, script, new UnwrapGoogLoadModule());
pushScript(new ScriptDescription()); // sets currentScript
currentScript.rootNode = script;
scriptDescriptions.addLast(currentScript);
NodeTraversal.traverse(compiler, script, new ScriptPreprocessor());
NodeTraversal.traverse(compiler, script, new ScriptRecorder());
popScript();
}
}
reportUnrecognizedRequires();
if (compiler.hasHaltingErrors()) {
return;
}
// Update scripts using the now complete googModuleNamespaces global state and unspool the
// scriptDescriptions that were queued up by all the recording.
NodeTraversal.traverseRoots(compiler, new ScriptUpdater(scriptDescriptions), externs, root);
declareSyntheticExterns();
this.googModuleGetCalls.forEach(this::updateGoogModuleGetCall);
this.googRequireDynamicCalls.forEach(this::updateGoogRequireDynamicCall);
}
/**
* Declares `var foo;` in the externs for all {@code synthetic_externs} names that aren't already
* in the global scope.
*
* Only add externs in the error case where there is an unrecognized goog.require or
* goog.module.get. Clutz depends on the compiler deleting local name declarations that alias or
* destructure the invalid call from this file. In order to preserve AST validity, we instead
* declare the deleted name in the externs. (which is fine with Clutz, as it just ignores the
* synthetic externs)
*/
private void declareSyntheticExterns() {
ImmutableList vars =
syntheticExterns.values().stream()
// Skip roots of goog.provide or goog.module.declareLegacyNamespace();
.filter((lhs) -> !isNameInGlobalScope(lhs.getString()))
.map(
(lhs) ->
IR.var(astFactory.createNameWithUnknownType(lhs.getString())).srcrefTree(lhs))
.collect(toImmutableList());
if (vars.isEmpty()) {
return;
}
Node root = compiler.getSynthesizedExternsInput().getAstRoot(compiler);
vars.forEach(root::addChildToBack);
}
/**
* Returns whether the name is declared in the global scope, either explicitly with var/const/let
* or implicitly by a goog.provide or legacy goog.module.
*/
private boolean isNameInGlobalScope(String name) {
return legacyScriptNamespacesAndPrefixes.contains(name) || globalScope.getVar(name) != null;
}
/**
* Rewrites object literal exports to the standard named exports style. i.e. exports = {Foo, Bar}
* to exports.Foo = Foo; exports.Bar = Bar; This makes the module exports into a more standard
* format for later passes.
*/
private void preprocessExportDeclaration(NodeTraversal t, Node n) {
if (!isGoogModuleExportsRef(t, n) || !isAssignTarget(n) || !n.getGrandparent().isExprResult()) {
return;
}
checkState(currentScript.defaultExport == null);
Node exportRhs = n.getNext();
if (NodeUtil.isNamedExportsLiteral(exportRhs)) {
Node insertionPoint = n.getGrandparent();
for (Node key = exportRhs.getFirstChild(); key != null; key = key.getNext()) {
String exportName = key.getString();
JSDocInfo jsdoc = key.getJSDocInfo();
Node rhs = key.removeFirstChild();
Node lhs =
astFactory
.createGetProp(astFactory.createName("exports", type(n)), exportName, type(rhs))
.srcrefTree(key);
Node newExport =
IR.exprResult(astFactory.createAssign(lhs, rhs).srcref(key).setJSDocInfo(jsdoc))
.srcref(key);
newExport.insertAfter(insertionPoint);
insertionPoint = newExport;
}
n.getGrandparent().detach();
}
}
private void recordModuleBody(Node moduleRoot) {
pushScript(new ScriptDescription());
currentScript.rootNode = moduleRoot;
currentScript.isModule = true;
}
private void recordGoogModule(NodeTraversal t, Node call) {
Node namespaceIdNode = call.getLastChild();
if (!namespaceIdNode.isStringLit()) {
t.report(namespaceIdNode, INVALID_MODULE_ID_ARG);
return;
}
String namespaceId = namespaceIdNode.getString();
currentScript.namespaceId = namespaceId;
currentScript.contentsPrefix = toModuleContentsPrefix(namespaceId);
Node scriptNode = NodeUtil.getEnclosingScript(currentScript.rootNode);
rewriteState.scriptDescriptionsByGoogModuleNamespace.put(namespaceId, currentScript);
rewriteState.namespaceIdsByScriptNode.put(scriptNode, namespaceId);
}
private void recordGoogDeclareLegacyNamespace() {
currentScript.declareLegacyNamespace = true;
updateLegacyScriptNamespacesAndPrefixes(currentScript.namespaceId);
}
private void updateLegacyScriptNamespacesAndPrefixes(String namespace) {
legacyScriptNamespacesAndPrefixes.add(namespace);
for (int dot = namespace.lastIndexOf('.'); dot != -1; dot = namespace.lastIndexOf('.')) {
namespace = namespace.substring(0, dot);
legacyScriptNamespacesAndPrefixes.add(namespace);
}
}
private void recordGoogProvide(NodeTraversal t, Node call) {
Node namespaceIdNode = call.getLastChild();
if (!namespaceIdNode.isStringLit()) {
t.report(namespaceIdNode, INVALID_PROVIDE_NAMESPACE);
return;
}
String namespaceId = namespaceIdNode.getString();
if (currentScript.isModule) {
t.report(namespaceIdNode, INVALID_PROVIDE_CALL);
}
Node scriptNode = NodeUtil.getEnclosingScript(call);
// Log legacy namespaces and prefixes.
rewriteState.providedNamespaces.add(namespaceId);
rewriteState.namespaceIdsByScriptNode.put(scriptNode, namespaceId);
updateLegacyScriptNamespacesAndPrefixes(namespaceId);
}
private void recordGoogRequire(NodeTraversal t, Node call, boolean mustBeOrdered) {
maybeSplitMultiVar(call);
Node namespaceIdNode = call.getLastChild();
if (!namespaceIdNode.isStringLit()) {
t.report(namespaceIdNode, INVALID_REQUIRE_NAMESPACE);
return;
}
String namespaceId = namespaceIdNode.getString();
// Maybe report an error if there is an attempt to import something that is expected to be a
// goog.module() but no such goog.module() has been defined.
boolean targetIsAModule = rewriteState.containsModule(namespaceId);
boolean targetIsALegacyScript = rewriteState.providedNamespaces.contains(namespaceId);
if (currentScript.isModule && !targetIsAModule && !targetIsALegacyScript) {
unrecognizedRequires.add(new UnrecognizedRequire(call, namespaceId, mustBeOrdered));
}
}
private void recordGoogRequireType(NodeTraversal t, Node call) {
Node namespaceIdNode = call.getLastChild();
if (!namespaceIdNode.isStringLit()) {
t.report(namespaceIdNode, INVALID_REQUIRE_TYPE_NAMESPACE);
return;
}
// For purposes of import collection, goog.requireType is the same as goog.require but
// a goog.requireType call is not required to appear after the corresponding namespace
// definition.
recordGoogRequire(t, call, /* mustBeOrdered= */ false);
}
private void recordGoogForwardDeclare(NodeTraversal t, Node call) {
Node namespaceNode = call.getLastChild();
if (!call.hasTwoChildren() || !namespaceNode.isStringLit()) {
t.report(namespaceNode, INVALID_FORWARD_DECLARE_NAMESPACE);
return;
}
// modules already require that goog.forwardDeclare() and goog.module.get() occur in matched
// pairs. If a "missing module" error were to occur here it would also occur in the matching
// goog.module.get(). To avoid reporting the error twice suppress it here.
boolean mustBeOrdered = false;
// For purposes of import collection, goog.forwardDeclare is the same as goog.require.
recordGoogRequire(t, call, mustBeOrdered);
}
private void recordGoogRequireDynamic(NodeTraversal t, Node call) {
Node namespaceIdNode = call.getLastChild();
if (!namespaceIdNode.isStringLit()) {
t.report(namespaceIdNode, INVALID_REQUIRE_DYNAMIC);
return;
}
String namespaceId = namespaceIdNode.getString();
if (!rewriteState.containsModule(namespaceId)) {
unrecognizedRequires.add(
new UnrecognizedRequire(call, namespaceId, /* mustBeOrdered= */ false));
}
this.googRequireDynamicCalls.add(call);
}
private void recordGoogModuleGet(NodeTraversal t, Node call) {
Node namespaceIdNode = call.getLastChild();
if (!call.hasTwoChildren() || !namespaceIdNode.isStringLit()) {
t.report(namespaceIdNode, INVALID_GET_NAMESPACE);
return;
}
String namespaceId = namespaceIdNode.getString();
if (!rewriteState.containsModule(namespaceId)) {
unrecognizedRequires.add(
new UnrecognizedRequire(call, namespaceId, /* mustBeOrdered= */ false));
}
this.googModuleGetCalls.add(call);
Node maybeAssign = call.getParent();
boolean isFillingAnAlias =
maybeAssign.isAssign()
&& maybeAssign.getFirstChild().isName()
&& maybeAssign.getParent().isExprResult();
if (!isFillingAnAlias || !currentScript.isModule) {
return;
}
String aliasName = call.getParent().getFirstChild().getString();
// If the assignment isn't into a var in our scope then it's not ok.
Var aliasVar = t.getScope().getVar(aliasName);
if (aliasVar == null) {
// Reported in CheckClosureImports
return;
}
// Even if it was to a var in our scope it should still only rewrite if the var looked like:
// let x = goog.forwardDeclare('a.namespace');
Node aliasVarNodeRhs = NodeUtil.getRValueOfLValue(aliasVar.getNode());
if (aliasVarNodeRhs == null
|| !NodeUtil.isCallTo(aliasVarNodeRhs, GOOG_FORWARDDECLARE)
|| !namespaceId.equals(aliasVarNodeRhs.getLastChild().getString())) {
// Reported in CheckClosureImports
return;
}
// Each goog.module.get() calling filling an alias will have the alias importing logic
// handled at the goog.forwardDeclare call, and the corresponding goog.module.get can simply
// be removed.
compiler.reportChangeToEnclosingScope(maybeAssign);
maybeAssign.getParent().detach();
this.googModuleGetCalls.remove(this.googModuleGetCalls.size() - 1);
}
private void recordTopLevelClassOrFunctionName(Node classOrFunctionNode) {
Node nameNode = classOrFunctionNode.getFirstChild();
if (nameNode.isName() && !Strings.isNullOrEmpty(nameNode.getString())) {
String name = nameNode.getString();
currentScript.topLevelNames.add(name);
}
}
private void recordTopLevelVarNames(Node varNode) {
NodeUtil.visitLhsNodesInNode(
varNode, (lhs) -> currentScript.topLevelNames.add(lhs.getString()));
}
private void maybeRecordExportDeclaration(NodeTraversal t, Node n) {
if (!currentScript.isModule || !isGoogModuleExportsRef(t, n) || !isAssignTarget(n)) {
return;
}
// ClosureCheckModule reports an error for duplicate 'exports = ' assignments, but that error
// may be suppressed. If so then use the final assignment as the canonical one.
if (currentScript.defaultExport != null) {
ExportDefinition previousExport = currentScript.defaultExport;
String localName = previousExport.getLocalName();
if (localName != null && currentScript.namesToInlineByAlias.containsKey(localName)) {
currentScript.namesToInlineByAlias.remove(localName);
}
currentScript.defaultExportLocalName = null;
}
Node exportRhs = n.getNext();
// Exports object should have already been converted in ScriptPreprocess step.
checkState(
!NodeUtil.isNamedExportsLiteral(exportRhs),
"Exports object should have been converted already");
currentScript.willCreateExportsObject = true;
ExportDefinition defaultExport = ExportDefinition.newDefaultExport(t, exportRhs);
currentScript.defaultExport = defaultExport;
if (!currentScript.declareLegacyNamespace
&& defaultExport.hasInlinableName(currentScript.exportsToInline.keySet())) {
String localName = defaultExport.getLocalName();
currentScript.defaultExportLocalName = localName;
recordExportToInline(defaultExport);
}
return;
}
private void updateModuleBodyEarly(Node moduleScopeRoot) {
pushScript(currentScript.removeFirstChildScript());
currentScript.rootNode = moduleScopeRoot;
}
private void updateGoogModule(NodeTraversal t, Node call) {
if (!currentScript.isModule) {
compiler.reportChangeToEnclosingScope(call);
Node undefined = astFactory.createVoid(astFactory.createNumber(0)).srcrefTree(call);
call.replaceWith(undefined);
return;
}
// If it's a goog.module() with a legacy namespace.
if (currentScript.declareLegacyNamespace) {
// Rewrite "goog.module('Foo');" as "goog.provide('Foo');".
call.getFirstChild().setString("provide");
compiler.reportChangeToEnclosingScope(call);
}
// If this script file isn't going to eventually create it's own exports object, then we know
// we'll need to do it ourselves, and so we might as well create it as early as possible to
// avoid ordering issues with goog.define().
if (!currentScript.willCreateExportsObject) {
checkState(!currentScript.hasCreatedExportObject, currentScript);
exportTheEmptyBinaryNamespaceAt(NodeUtil.getEnclosingStatement(call), AddAt.AFTER, t);
}
if (!currentScript.declareLegacyNamespace && !preserveSugar) {
// Otherwise it's a regular module and the goog.module() line can be removed.
compiler.reportChangeToEnclosingScope(call);
NodeUtil.getEnclosingStatement(call).detach();
}
}
private static void updateGoogDeclareLegacyNamespace(Node call) {
NodeUtil.getEnclosingStatement(call).detach();
}
private void updateGoogRequire(NodeTraversal t, Node call) {
Node namespaceIdNode = call.getLastChild();
Node statementNode = NodeUtil.getEnclosingStatement(call);
String namespaceId = namespaceIdNode.getString();
boolean targetIsNonLegacyGoogModule =
rewriteState.containsModule(namespaceId) && !rewriteState.isLegacyModule(namespaceId);
boolean importHasAlias = NodeUtil.isNameDeclaration(statementNode);
boolean isDestructuring = statementNode.getFirstChild().isDestructuringLhs();
// If the current script is a module or the require statement has a return value that is stored
// in an alias then the require is goog.module() style.
boolean currentScriptIsAModule = currentScript.isModule;
// "var Foo = goog.require("bar.Foo");" or "const {Foo} = goog.require('bar');" style.
boolean requireDirectlyStoredInAlias = NodeUtil.isNameDeclaration(call.getGrandparent());
if (currentScriptIsAModule
&& requireDirectlyStoredInAlias
&& isTopLevel(t, statementNode, ScopeType.EXEC_CONTEXT)) {
// Record alias -> exportedNamespace associations for later inlining.
Node lhs = call.getParent();
String exportedNamespace = rewriteState.getExportedNamespaceOrScript(namespaceId);
if (exportedNamespace == null) {
// There's nothing to inline. The missing provide/module will be reported elsewhere.
} else if (lhs.isName()) {
// `var Foo` case
String aliasName = statementNode.getFirstChild().getString();
recordNameToInline(aliasName, exportedNamespace, namespaceId);
maybeAddAliasToSymbolTable(statementNode.getFirstChild(), currentScript.namespaceId);
} else if (lhs.isDestructuringLhs() && lhs.getFirstChild().isObjectPattern()) {
// `const {Foo}` case
maybeWarnForInvalidDestructuring(t, lhs.getParent(), namespaceId);
for (Node importSpec = lhs.getFirstFirstChild();
importSpec != null;
importSpec = importSpec.getNext()) {
checkState(importSpec.hasChildren(), importSpec);
String importedProperty = importSpec.getString();
Node aliasNode = importSpec.getFirstChild();
String aliasName = aliasNode.getString();
String fullName = exportedNamespace + "." + importedProperty;
recordNameToInline(aliasName, fullName, /* namespaceId= */ null);
// Record alias before we rename node.
maybeAddAliasToSymbolTable(aliasNode, currentScript.namespaceId);
// Need to rename node otherwise it will stay global and messes up index if there are
// other files that use the same destructuring alias.
safeSetString(aliasNode, currentScript.contentsPrefix + aliasName);
}
} else {
throw new RuntimeException("Illegal goog.module import: " + lhs);
}
}
if (currentScript.isModule || targetIsNonLegacyGoogModule) {
if (isDestructuring) {
if (!preserveSugar) {
// Delete the goog.require() because we're going to inline its alias later.
compiler.reportChangeToEnclosingScope(statementNode);
statementNode.detach();
}
} else if (targetIsNonLegacyGoogModule) {
checkState(
isTopLevel(t, statementNode, ScopeType.EXEC_CONTEXT),
"Unexpected non-top-level require at %s",
call);
if (importHasAlias || !rewriteState.isLegacyModule(namespaceId)) {
if (!preserveSugar) {
// Delete the goog.require() because we're going to inline its alias later.
compiler.reportChangeToEnclosingScope(statementNode);
statementNode.detach();
}
}
} else {
// TODO(bangert): make this compatible with preserveSugar. const B = goog.require('b') runs
// into problems because the type checker cannot handle const.
// Rewrite
// "var B = goog.require('B');" to
// "goog.require('B');"
// because even though we're going to inline the B alias,
// ProcessClosurePrimitives is going to want to see this legacy require.
call.detach();
statementNode.replaceWith(IR.exprResult(call));
compiler.reportChangeToEnclosingScope(call);
}
}
}
// These restrictions are in place to make it easier to migrate goog.modules to ES6 modules,
// by structuring the imports/exports in a consistent way.
private void maybeWarnForInvalidDestructuring(
NodeTraversal t, Node importNode, String importedNamespace) {
checkArgument(importNode.getFirstChild().isDestructuringLhs(), importNode);
ScriptDescription importedModule =
rewriteState.scriptDescriptionsByGoogModuleNamespace.get(importedNamespace);
if (importedModule == null) {
// Don't know enough to give a good warning here.
return;
}
if (importedModule.defaultExport != null) {
t.report(importNode, ILLEGAL_DESTRUCTURING_DEFAULT_EXPORT);
return;
}
Node objPattern = importNode.getFirstFirstChild();
for (Node key = objPattern.getFirstChild(); key != null; key = key.getNext()) {
String exportName = key.getString();
if (!importedModule.namedExports.contains(exportName)) {
t.report(importNode, ILLEGAL_DESTRUCTURING_NOT_EXPORTED, exportName, importedNamespace);
}
}
}
private void updateGoogForwardDeclare(NodeTraversal t, Node call) {
// For import rewriting purposes and when taking into account previous moduleAlias versus
// namespaceId import categorization, goog.forwardDeclare is much the same as goog.require.
updateGoogRequire(t, call);
}
private void updateGoogRequireDynamicCall(Node call) {
final Node parent = call.getParent();
checkState(
parent.isAwait() || (parent.isGetProp() && parent.getString().equals("then")),
"goog.requireDynamic() in only allowed in await/then expression");
if (parent.isAwait()) {
updateGoogRequireDynamicCallInAwait(call);
} else {
updateGoogRequireDynamicCallInThen(call);
}
}
// Rewrite
// goog.requireDynamic('a.b.c').then( ({Foo}) => { new Foo().render(); });
// to
// goog.importHandler_('h4sh').then(() => {
// const {Foo} = module$exports$a$b$c;
// new Foo().render();
// });
// Note that rewriting works for both destructuring pattern and name, i.e., `{Foo}` or `foo`.
private void updateGoogRequireDynamicCallInThen(Node call) {
Node namespaceIdNode = call.getSecondChild();
String namespaceId = namespaceIdNode.getString();
String exportedNamespace = rewriteState.getExportedNamespaceOrScript(namespaceId);
checkState(
exportedNamespace != null, "Exported namespace for goog.requireDynamic() canot be null");
// `goog.requireDynamic('a.b.c').then()`
final Node getProp = call.getParent();
final Node thenCallNode = getProp.getParent();
checkState(thenCallNode != null && thenCallNode.isCall(), "must be a 'then' call expression");
// Create a string literal containing the ID of the chunk containing the module we want
Node argNode =
this.astFactory.createString(namespaceIdToXid(namespaceId)).srcref(namespaceIdNode);
// `goog.requireDynamic('a.b.c')` -> `goog.requireDynamic('chunkId')`
namespaceIdNode.replaceWith(argNode);
// `goog.requireDynamic` -> `goog.importHandler_`
Node calleeNode = call.getFirstChild();
checkState(calleeNode.matchesQualifiedName(GOOG_REQUIREDYNAMIC_NAME), calleeNode);
calleeNode.setString(IMPORT_HANDLER_NAME);
// `module$exports$a$b$c`
Node exportedNamespaceNameNode =
this.astFactory.createName(this.globalTypedScope, exportedNamespace).srcrefTree(call);
exportedNamespaceNameNode.setOriginalName(namespaceId);
// Get `{Foo}` from `goog.requireDynamic().then( ({Foo}) => { } )`;
Node functionNode = thenCallNode.getSecondChild();
checkState(functionNode != null && functionNode.isFunction(), "must be a function in `then`");
// Get param list of the callback function
Node paramListNode = functionNode.getSecondChild();
checkState(paramListNode.getChildCount() == 1, "function must have only one parameter");
// Get the callback function body
Node functionBody = paramListNode.getNext();
// Get parameter, object pattern or name
Node objectPatternOrNameNode = paramListNode.getOnlyChild();
checkState(
objectPatternOrNameNode.isObjectPattern() || objectPatternOrNameNode.isName(),
"parameter of callback function must be object pattern or name");
objectPatternOrNameNode.detach();
// `({Foo}) => {}` -> `() => {}`
paramListNode.removeChildren();
// Dynamic require is not allowed for JS that is too old to have `const` (< ES6),
// We don't expect to ever see `--language_in=ES5` in combination with dynamic require.
final LanguageMode languageIn = compiler.getOptions().getLanguageIn();
checkState(
languageIn.toFeatureSet().contains(Feature.CONST_DECLARATIONS),
"'%s' does not contain '%s'",
languageIn,
Feature.CONST_DECLARATIONS);
Node enclosingScript = NodeUtil.getEnclosingScript(call);
NodeUtil.addFeatureToScript(enclosingScript, Feature.CONST_DECLARATIONS, compiler);
// Create `const {Foo} = module$exports$a$b$c;`
// Or `const foo = module$exports$a$b$c;'
Node declarationNode;
if (objectPatternOrNameNode.isObjectPattern()) {
declarationNode =
this.astFactory
.createSingleConstObjectPatternDeclaration(
objectPatternOrNameNode, exportedNamespaceNameNode)
.srcrefTreeIfMissing(call);
} else {
declarationNode =
this.astFactory
.createSingleConstNameDeclaration(
objectPatternOrNameNode.getString(), exportedNamespaceNameNode)
.srcrefTreeIfMissing(call);
}
functionBody.addChildToFront(declarationNode);
compiler.reportChangeToEnclosingScope(call);
compiler.reportChangeToEnclosingScope(declarationNode);
}
// Rewrite
// const {Foo} = await goog.requireDynamic('a.b.c')`
// to
// await goog.importHandler_('tJJovc');
// const {Foo} = module$exports$a$b$c;
private void updateGoogRequireDynamicCallInAwait(Node call) {
Node namespaceIdNode = call.getSecondChild();
String namespaceId = namespaceIdNode.getString();
String exportedNamespace = rewriteState.getExportedNamespaceOrScript(namespaceId);
checkState(
exportedNamespace != null, "Exported namespace for goog.requireDynamic() cannot be null");
// `await goog.requireDynamic('a.b.c')`
final Node existingAwait = call.getParent();
checkState(
existingAwait.isAwait(), "Only goog.requireDynamic() in await expression is supported now");
// `{Foo} = await goog.requireDynamic('a.b.c')`
Node awaitParent = existingAwait.getParent();
checkState(
awaitParent != null && (awaitParent.isDestructuringLhs() || awaitParent.isName()),
"LHS must be a destructing LHS or name");
// `const {Foo} = await goog.requireDynamic('a.b.c')`
Node declarationStatement = awaitParent.getParent();
// Reject non-declarations or declarations in a for loop.
checkState(
NodeUtil.isNameDeclaration(declarationStatement)
&& NodeUtil.isStatement(declarationStatement),
"must be a declaration statement");
// `module$exports$a$b$c`
Node exportedNamespaceNameNode =
this.astFactory.createQName(this.globalTypedScope, exportedNamespace).srcrefTree(call);
exportedNamespaceNameNode.setJSType(rewriteState.getGoogModuleNamespaceType(namespaceId));
exportedNamespaceNameNode.setOriginalName(namespaceId);
// Create a string literal containing the ID of the chunk containing the module we want
Node argNode =
this.astFactory.createString(namespaceIdToXid(namespaceId)).srcref(namespaceIdNode);
// `goog.requireDynamic('a.b.c')` -> `goog.requireDynamic('chunkId')`
namespaceIdNode.replaceWith(argNode);
// `goog.requireDynamic` -> `goog.importHandler_`
Node calleeNode = call.getFirstChild();
checkState(calleeNode.matchesQualifiedName(GOOG_REQUIREDYNAMIC_NAME), calleeNode);
calleeNode.setString(IMPORT_HANDLER_NAME);
// Replace the await with the module object
// `const {Foo} = module$exports$a$b$c;`
existingAwait.replaceWith(exportedNamespaceNameNode);
// Insert the await as a statement before the declaration
final Node awaitStatement = astFactory.exprResult(existingAwait).srcref(existingAwait);
awaitStatement.insertBefore(declarationStatement);
compiler.reportChangeToEnclosingScope(call);
}
private String namespaceIdToXid(String namespaceId) {
Xid.HashFunction hashFunction = this.compiler.getOptions().chunkIdHashFunction;
Xid xid = hashFunction == null ? new Xid() : new Xid(hashFunction);
return xid.get(namespaceId);
}
private void updateGoogModuleGetCall(Node call) {
Node namespaceIdNode = call.getSecondChild();
String namespaceId = namespaceIdNode.getString();
// Remaining calls to goog.module.get() are not alias updates,
// and should be replaced by a reference to the proper name.
// Replace "goog.module.get('pkg.Foo')" with either "pkg.Foo" or "module$exports$pkg$Foo".
String exportedNamespace = rewriteState.getExportedNamespaceOrScript(namespaceId);
if (exportedNamespace != null) {
compiler.reportChangeToEnclosingScope(call);
Node exportedNamespaceName =
this.astFactory
.createQNameFromTypedScope(this.globalTypedScope, exportedNamespace)
.srcrefTree(call);
exportedNamespaceName.setJSType(rewriteState.getGoogModuleNamespaceType(namespaceId));
exportedNamespaceName.setOriginalName(namespaceId);
call.replaceWith(exportedNamespaceName);
}
}
private void recordExportsPropertyAssignment(NodeTraversal t, Node getpropNode) {
if (!currentScript.isModule) {
return;
}
Node parent = getpropNode.getParent();
checkState(parent.isAssign() || parent.isExprResult(), parent);
Node exportsNameNode = getpropNode.getFirstChild();
checkState(exportsNameNode.getString().equals("exports"), exportsNameNode);
if (t.inModuleScope()) {
String exportName = getpropNode.getString();
currentScript.namedExports.add(exportName);
Node exportRhs = getpropNode.getNext();
ExportDefinition namedExport = ExportDefinition.newNamedExport(t, exportName, exportRhs);
if (!currentScript.declareLegacyNamespace
&& currentScript.defaultExport == null
&& namedExport.hasInlinableName(currentScript.exportsToInline.keySet())) {
recordExportToInline(namedExport);
parent.getParent().detach();
}
}
}
private void updateExportsPropertyAssignment(Node getpropNode, NodeTraversal t) {
if (!currentScript.isModule) {
return;
}
Node parent = getpropNode.getParent();
checkState(parent.isAssign() || parent.isExprResult(), parent);
// Update "exports.foo = Foo" to "module$exports$pkg$Foo.foo = Foo";
Node exportsNameNode = getpropNode.getFirstChild();
checkState(exportsNameNode.getString().equals("exports"));
String exportedNamespace = currentScript.getExportedNamespace();
safeSetMaybeQualifiedString(exportsNameNode, exportedNamespace, /* isModuleNamespace= */ false);
Node jsdocNode = parent.isAssign() ? parent : getpropNode;
markConstAndCopyJsDoc(jsdocNode, jsdocNode);
// When seeing the first "exports.foo = ..." line put a "var module$exports$pkg$Foo = {};"
// before it.
if (!currentScript.hasCreatedExportObject) {
exportTheEmptyBinaryNamespaceAt(NodeUtil.getEnclosingStatement(parent), AddAt.BEFORE, t);
}
}
/**
* Rewrites top level var names from "var foo; console.log(foo);" to "var module$contents$Foo_foo;
* console.log(module$contents$Foo_foo);"
*/
private void maybeUpdateTopLevelName(NodeTraversal t, Node nameNode) {
String name = nameNode.getString();
if (!currentScript.isModule || !currentScript.topLevelNames.contains(name)) {
return;
}
Var var = t.getScope().getVar(name);
// If the name refers to a var that is not from the top level scope.
if (var == null || var.getScope().getRootNode() != currentScript.rootNode) {
// Then it shouldn't be renamed.
return;
}
// If the name is part of a destructuring import, the import rewriting will take care of it
if (var.getNameNode() == nameNode
&& nameNode.getParent().isStringKey()
&& nameNode.getGrandparent().isObjectPattern()) {
Node destructuringLhsNode = nameNode.getGrandparent().getParent();
if (NodeUtil.isCallTo(destructuringLhsNode.getLastChild(), GOOG_REQUIRE)
|| NodeUtil.isCallTo(destructuringLhsNode.getLastChild(), GOOG_REQUIRETYPE)) {
return;
}
}
// If the name is an alias for an imported namespace or an exported local, rewrite from
// "new Foo;" to "new module$exports$Foo;" or "new Foo" to "new module$contents$bar$Foo".
boolean nameIsAnAlias = currentScript.namesToInlineByAlias.containsKey(name);
if (nameIsAnAlias && var.getNode() != nameNode) {
maybeAddAliasToSymbolTable(nameNode, currentScript.namespaceId);
AliasName inline = currentScript.namesToInlineByAlias.get(name);
String namespaceToInline = inline.newName;
if (namespaceToInline.equals(currentScript.getBinaryNamespace())) {
currentScript.hasCreatedExportObject = true;
}
boolean isModuleNamespace =
inline.namespaceId != null
&& rewriteState.scriptDescriptionsByGoogModuleNamespace.containsKey(
inline.namespaceId)
&& !rewriteState.scriptDescriptionsByGoogModuleNamespace.get(inline.namespaceId)
.willCreateExportsObject;
safeSetMaybeQualifiedString(nameNode, namespaceToInline, isModuleNamespace);
// Make sure this action won't shadow a local variable.
if (namespaceToInline.indexOf('.') != -1) {
String firstQualifiedName = namespaceToInline.substring(0, namespaceToInline.indexOf('.'));
Var shadowedVar = t.getScope().getVar(firstQualifiedName);
if (shadowedVar == null
|| shadowedVar.isGlobal()
|| shadowedVar.getScope().isModuleScope()) {
return;
}
t.report(
shadowedVar.getNode(),
IMPORT_INLINING_SHADOWS_VAR,
shadowedVar.getName(),
namespaceToInline);
}
return;
}
// For non-import alias names rewrite from
// "var foo; console.log(foo);" to
// "var module$contents$Foo_foo; console.log(module$contents$Foo_foo);"
safeSetString(nameNode, currentScript.contentsPrefix + name);
}
/**
* For exports like "exports = {prop: value}" update the declarations to enforce @const ness
* (and typedef exports).
*
* TODO(blickly): Remove as much of this functionality as possible, now that these style of
* exports are rewritten in ScriptPreprocess step.
*/
private void maybeUpdateExportObjectLiteral(NodeTraversal t, Node n) {
if (!currentScript.isModule) {
return;
}
Node parent = n.getParent();
Node rhs = parent.getLastChild();
if (rhs.isObjectLit()) {
for (Node c = rhs.getFirstChild(); c != null; c = c.getNext()) {
if (c.isComputedProp()) {
t.report(c, INVALID_EXPORT_COMPUTED_PROPERTY);
} else if (c.isStringKey()) {
Node value = c.getFirstChild();
maybeUpdateExportDeclToNode(t, c, value);
}
}
}
}
private void maybeUpdateExportDeclToNode(NodeTraversal t, Node target, Node value) {
if (!currentScript.isModule) {
return;
}
// If the RHS is a typedef, clone the declaration.
// Hack alert: clone the typedef declaration if one exists
// this is a simple attempt that covers the common case of the
// exports being in the same scope as the typedef declaration.
// Otherwise the type name might be invalid.
if (value.isName()) {
Scope currentScope = t.getScope();
Var v = t.getScope().getVar(value.getString());
if (v != null) {
AbstractScope varScope = v.getScope();
if (varScope.getDepth() == currentScope.getDepth()) {
JSDocInfo info = v.getJSDocInfo();
if (info != null && info.hasTypedefType()) {
JSDocInfo.Builder builder = JSDocInfo.Builder.copyFrom(info);
target.setJSDocInfo(builder.build());
return;
}
}
}
}
markConstAndCopyJsDoc(target, target);
}
/** In module "foo.Bar", rewrite "exports = Bar" to "var module$exports$foo$Bar = Bar". */
private void maybeUpdateExportDeclaration(NodeTraversal t, Node n) {
if (!currentScript.isModule || !isGoogModuleExportsRef(t, n) || !isAssignTarget(n)) {
return;
}
Node assignNode = n.getParent();
Node rhs = assignNode.getLastChild();
if (rhs != currentScript.defaultExport.rhs) {
// This script has duplicate 'exports = ' assignments. Preserve the rhs as an expression but
// don't declare it as a global variable.
assignNode.replaceWith(rhs.detach());
return;
}
if (!currentScript.declareLegacyNamespace && currentScript.defaultExportLocalName != null) {
assignNode.getParent().detach();
Node binaryNamespaceName = astFactory.createName(currentScript.getBinaryNamespace(), type(n));
this.declareGlobalVariable(binaryNamespaceName, t);
return;
}
// Rewrite "exports = ..." as "var module$exports$foo$Bar = ..."
Node jsdocNode;
if (currentScript.declareLegacyNamespace) {
Node legacyQname =
this.astFactory
.createQName(this.globalTypedScope, currentScript.namespaceId)
.srcrefTree(n);
legacyQname.setJSType(n.getJSType());
n.replaceWith(legacyQname);
jsdocNode = assignNode;
} else {
rhs.detach();
Node exprResultNode = assignNode.getParent();
Node binaryNamespaceName = astFactory.createName(currentScript.getBinaryNamespace(), type(n));
binaryNamespaceName.setOriginalName("exports");
this.declareGlobalVariable(binaryNamespaceName, t);
Node exportsObjectCreationNode = IR.var(binaryNamespaceName, rhs);
exportsObjectCreationNode.srcrefTreeIfMissing(exprResultNode);
exportsObjectCreationNode.putBooleanProp(Node.IS_NAMESPACE, true);
exprResultNode.replaceWith(exportsObjectCreationNode);
jsdocNode = exportsObjectCreationNode;
currentScript.hasCreatedExportObject = true;
}
markConstAndCopyJsDoc(assignNode, jsdocNode);
compiler.reportChangeToEnclosingScope(jsdocNode);
maybeUpdateExportObjectLiteral(t, rhs);
return;
}
private void maybeUpdateExportNameRef(NodeTraversal t, Node n) {
if (!currentScript.isModule || !isGoogModuleExportsRef(t, n) || n.getParent() == null) {
return;
}
if (n.getParent().isParamList()) {
return;
}
if (currentScript.declareLegacyNamespace) {
Node legacyQname =
this.astFactory
.createQName(this.globalTypedScope, currentScript.namespaceId)
.srcrefTree(n);
legacyQname.setJSType(n.getJSType());
n.replaceWith(legacyQname);
compiler.reportChangeToEnclosingScope(legacyQname);
return;
}
safeSetString(n, currentScript.getBinaryNamespace());
// Either this module is going to create it's own exports object at some point or else if it's
// going to be defensively created automatically then that should have occurred at the top of
// the file and been done by now.
checkState(currentScript.willCreateExportsObject || currentScript.hasCreatedExportObject);
}
void updateModuleBody(Node moduleBody) {
checkArgument(
moduleBody.isModuleBody() && moduleBody.getParent().getBooleanProp(Node.GOOG_MODULE),
moduleBody);
moduleBody.setToken(Token.BLOCK);
NodeUtil.tryMergeBlock(moduleBody, true);
for (ExportDefinition export : currentScript.exportsToInline.values()) {
Node nameNode = export.nameDecl.getNameNode();
safeSetMaybeQualifiedString(
nameNode, currentScript.getBinaryNamespace() + export.getExportPostfix(), false);
}
checkState(currentScript.isModule, currentScript);
checkState(
currentScript.declareLegacyNamespace || currentScript.hasCreatedExportObject,
currentScript);
popScript();
}
/**
* Record the provided script as the current script at top of the script stack and add it as a
* child of the previous current script if there was one.
*
*
Keeping track of the current script facilitates aggregation of accurate script state so that
* rewriting can run properly. Handles scripts and nested goog.modules.
*/
private void pushScript(ScriptDescription newCurrentScript) {
currentScript = newCurrentScript;
if (!scriptStack.isEmpty()) {
ScriptDescription parentScript = scriptStack.peek();
parentScript.addChildScript(currentScript);
}
scriptStack.addFirst(currentScript);
}
private void popScript() {
scriptStack.removeFirst();
currentScript = scriptStack.peekFirst();
}
/** Add the missing "var module$exports$pkg$Foo = {};" line. */
private void exportTheEmptyBinaryNamespaceAt(Node atNode, AddAt addAt, NodeTraversal t) {
if (currentScript.declareLegacyNamespace) {
return;
}
String binaryNamespaceString = currentScript.getBinaryNamespace();
AstFactory.Type moduleType = type(currentScript.rootNode);
Node binaryNamespaceName = astFactory.createName(binaryNamespaceString, moduleType);
binaryNamespaceName.setOriginalName(currentScript.namespaceId);
this.declareGlobalVariable(binaryNamespaceName, t);
Node binaryNamespaceExportNode = IR.var(binaryNamespaceName, astFactory.createObjectLit());
if (addAt == AddAt.BEFORE) {
binaryNamespaceExportNode.insertBefore(atNode);
} else if (addAt == AddAt.AFTER) {
binaryNamespaceExportNode.insertAfter(atNode);
}
binaryNamespaceExportNode.putBooleanProp(Node.IS_NAMESPACE, true);
binaryNamespaceExportNode.srcrefTree(atNode);
markConst(binaryNamespaceExportNode);
compiler.reportChangeToEnclosingScope(binaryNamespaceExportNode);
currentScript.hasCreatedExportObject = true;
}
static void checkAndSetStrictModeDirective(NodeTraversal t, Node n) {
checkState(n.isScript(), n);
if (n.isUseStrict()) {
t.report(n, USELESS_USE_STRICT_DIRECTIVE);
} else {
n.setUseStrict(true);
}
}
private static void markConst(Node n) {
JSDocInfo.Builder builder = JSDocInfo.Builder.maybeCopyFrom(n.getJSDocInfo());
builder.recordConstancy();
n.setJSDocInfo(builder.build());
}
private static void maybeSplitMultiVar(Node rhsNode) {
Node statementNode = rhsNode.getGrandparent();
if (!statementNode.isVar() || !statementNode.hasMoreThanOneChild()) {
return;
}
Node nameNode = rhsNode.getParent();
nameNode.detach();
rhsNode.detach();
IR.var(nameNode, rhsNode).insertBefore(statementNode);
}
private static void markConstAndCopyJsDoc(Node from, Node target) {
JSDocInfo info = from.getJSDocInfo();
JSDocInfo.Builder builder = JSDocInfo.Builder.maybeCopyFrom(info);
builder.recordConstancy();
target.setJSDocInfo(builder.build());
}
private void recordExportToInline(ExportDefinition exportDefinition) {
checkState(
exportDefinition.hasInlinableName(currentScript.exportsToInline.keySet()),
"exportDefinition: %s\n\nexportsToInline keys: %s",
exportDefinition,
currentScript.exportsToInline.keySet());
checkState(
null == currentScript.exportsToInline.put(exportDefinition.nameDecl, exportDefinition),
"Already found a mapping for inlining export: %s",
exportDefinition.nameDecl);
String localName = exportDefinition.getLocalName();
String fullExportedName =
currentScript.getBinaryNamespace() + exportDefinition.getExportPostfix();
recordNameToInline(localName, fullExportedName, /* namespaceId= */ null);
}
private void recordNameToInline(String aliasName, String newName, @Nullable String namespaceId) {
checkNotNull(aliasName);
checkNotNull(newName);
// This intentionally overwrites a possibly pre-existing alias of the same name.
// User code might import the same name twice, with the same variable name. That's an error
// (duplicate variable definition, reported in TypeValidator), but this code still shouldn't
// crash on it.
currentScript.namesToInlineByAlias.put(aliasName, new AliasName(newName, namespaceId));
}
/**
* Examines queue'ed unrecognizedRequires to categorize and report them as either missing module,
* missing namespace or late provide.
*/
private void reportUnrecognizedRequires() {
for (UnrecognizedRequire unrecognizedRequire : unrecognizedRequires) {
String namespaceId = unrecognizedRequire.namespaceId;
Node requireNode = unrecognizedRequire.requireNode;
boolean targetGoogModuleExists = rewriteState.containsModule(namespaceId);
boolean targetLegacyScriptExists = rewriteState.providedNamespaces.contains(namespaceId);
if (targetGoogModuleExists || targetLegacyScriptExists) {
// The required thing actually was available somewhere in the program but just wasn't
// available as early as the require statement would have liked.
continue;
}
// Remove the require node so this problem isn't reported again in ProcessClosurePrimitives.
if (preserveSugar) {
continue;
}
if (NodeUtil.getEnclosingScript(requireNode) == null) {
continue; // It's already been removed; nothing to do.
}
compiler.reportChangeToEnclosingScope(requireNode);
Node enclosingStatement = NodeUtil.getEnclosingStatement(requireNode);
// To make compilation with partial source information work for Clutz, delete any name
// declarations in the enclosing statement completely. For non-declarations, simply replace
// the invalid require with null.
if (!NodeUtil.isNameDeclaration(enclosingStatement)) {
requireNode.replaceWith(astFactory.createNull().srcref(requireNode));
continue;
}
enclosingStatement.detach();
NodeUtil.visitLhsNodesInNode(
enclosingStatement, (lhs) -> syntheticExterns.putIfAbsent(lhs.getString(), lhs));
}
}
private void safeSetString(Node n, String newString) {
if (n.getString().equals(newString)) {
return;
}
String originalName = n.getString();
n.setString(newString);
if (n.getOriginalName() == null) {
n.setOriginalName(originalName);
}
// TODO(blickly): It would be better not to be renaming detached nodes
Node changeScope = NodeUtil.getEnclosingChangeScopeRoot(n);
if (changeScope != null) {
compiler.reportChangeToChangeScope(changeScope);
}
}
/** Replaces an identifier with a potentially qualified name */
private void safeSetMaybeQualifiedString(
Node nameNode, String newString, boolean isModuleNamespace) {
if (!newString.contains(".")) {
safeSetString(nameNode, newString);
Node parent = nameNode.getParent();
if (isModuleNamespace
&& parent.isGetProp()
&& nameNode.getGrandparent().isCall()
&& parent.isFirstChildOf(nameNode.getGrandparent())) {
// In cases where we're calling a function off a module namespace, don't pass the module
// namespace as `this`.
nameNode.getGrandparent().putBooleanProp(Node.FREE_CALL, true);
}
return;
}
// When replacing with a dotted fully qualified name it's already better than an original
// name.
Node nameParent = nameNode.getParent();
Node newQualifiedName =
this.astFactory
.createQNameFromTypedScope(this.globalTypedScope, newString)
.srcrefTree(nameNode);
boolean replaced = safeSetStringIfDeclaration(nameParent, nameNode, newQualifiedName);
if (replaced) {
return;
}
nameNode.replaceWith(newQualifiedName);
// Given import "var Bar = goog.require('foo.Bar');" here we replace a usage of Bar with
// foo.Bar if Bar is goog.provided. 'foo' node is generated and never visible to user.
// Because of that we should mark all such nodes as non-indexable leaving only Bar indexable.
// Given that replacement is GETPROP node, prefix is first child. It's also possible that
// replacement is single-part namespace. Like goog.provide('Bar') in that case replacement
// won't have children.
if (newQualifiedName.hasChildren()) {
newQualifiedName.getFirstChild().makeNonIndexableRecursive();
}
compiler.reportChangeToEnclosingScope(newQualifiedName);
}
/** Sets the string if given a declaration, return whether or not the name was changed */
private static boolean safeSetStringIfDeclaration(
Node nameParent, Node nameNode, Node newQualifiedName) {
JSDocInfo jsdoc = nameParent.getJSDocInfo();
switch (nameParent.getToken()) {
case FUNCTION:
case CLASS:
if (!NodeUtil.isStatement(nameParent) || nameParent.getFirstChild() != nameNode) {
return false;
}
Node placeholder = IR.empty();
nameParent.replaceWith(placeholder);
Node newDeclaration =
NodeUtil.getDeclarationFromName(newQualifiedName, nameParent, Token.VAR, jsdoc);
if (NodeUtil.isExprAssign(newDeclaration)) {
Node assign = newDeclaration.getOnlyChild();
assign.setJSType(nameNode.getJSType());
updateSourceInfoForExportedTopLevelVariable(assign, nameNode);
}
nameParent.setJSDocInfo(null);
newDeclaration.srcrefTreeIfMissing(nameParent);
placeholder.replaceWith(newDeclaration);
NodeUtil.removeName(nameParent);
return true;
case VAR:
case LET:
case CONST:
Node rhs = nameNode.hasChildren() ? nameNode.getLastChild().detach() : null;
if (jsdoc == null) {
// Get inline JSDocInfo if there is no JSDoc on the actual declaration.
jsdoc = nameNode.getJSDocInfo();
}
Node newStatement =
NodeUtil.getDeclarationFromName(newQualifiedName, rhs, Token.VAR, jsdoc);
if (NodeUtil.isExprAssign(newStatement)) {
Node assign = newStatement.getOnlyChild();
assign.setJSType(nameNode.getJSType());
updateSourceInfoForExportedTopLevelVariable(assign, nameNode);
if (nameParent.isConst()) {
// When replacing `const name = ...;` with `some.prop = ...`, ensure that `some.prop`
// is annotated @const.
JSDocInfo.Builder jsdocBuilder = JSDocInfo.Builder.maybeCopyFrom(jsdoc);
jsdocBuilder.recordConstancy();
jsdoc = jsdocBuilder.build();
assign.setJSDocInfo(jsdoc);
}
}
newStatement.srcrefTreeIfMissing(nameParent);
NodeUtil.replaceDeclarationChild(nameNode, newStatement);
return true;
case OBJECT_PATTERN:
case ARRAY_PATTERN:
case PARAM_LIST:
throw new RuntimeException("Not supported");
default:
break;
}
return false;
}
/**
* If we had something like `const FOO = "text"` and we export `FOO`, change the source location
* information for the rewritten FOO. The replacement should be something like MOD.FOO = "text",
* so we look for MOD.FOO and replace the source location for FOO to the original location of FOO.
*/
private static void updateSourceInfoForExportedTopLevelVariable(Node assign, Node sourceName) {
checkState(assign.isAssign());
checkState(sourceName.isName());
// ASSIGN always has two children.
Node getProp = assign.getFirstChild();
if (!getProp.isGetProp()) {
return;
}
String name = sourceName.getOriginalName();
if (name == null) {
name = sourceName.getString();
}
// The source range of this NAME includes its declared value, which we don't want.
sourceName = sourceName.cloneNode();
sourceName.setLength(name.length());
// Receiver and prop string should both use the position of the source name.
getProp.srcrefTree(sourceName);
}
private boolean isTopLevel(NodeTraversal t, Node n, ScopeType scopeType) {
if (scopeType == ScopeType.EXEC_CONTEXT) {
return t.inGlobalScope() || t.getClosestHoistScopeRoot() == currentScript.rootNode;
} else {
// Must be ScopeType.BLOCK;
return n.getParent() == currentScript.rootNode;
}
}
private static String toModuleContentsPrefix(String namespaceId) {
return MODULE_CONTENTS_PREFIX + namespaceId.replace('.', '$') + "_";
}
public static boolean isModuleExport(String name) {
return name.startsWith(MODULE_EXPORTS_PREFIX);
}
public static boolean isModuleContent(String name) {
return name.startsWith(MODULE_CONTENTS_PREFIX);
}
/**
* Returns whether this is a) a reference to the name "exports" and b) based on scoping, actually
* refers to the implicit goog.module exports object.
*/
private static boolean isGoogModuleExportsRef(NodeTraversal t, Node target) {
if (!target.isName() || !target.matchesName("exports")) {
return false;
}
Var exportsVar = t.getScope().getVar("exports");
// note: exportsVar may be null for third-party code using UMD patterns like
// if ("object"==typeof exports) { [...]
// and if null, is not in a goog.module => not a goog.module exports var
return exportsVar != null && exportsVar.isGoogModuleExports();
}
/**
* @return Whether the getprop is used as an assignment target, and that target represents a
* module export. Note: that "export.name = value" is an export, while "export.name.foo =
* value" is not (it is an assignment to a property of an exported value).
*/
private static boolean isExportPropertyAssignment(NodeTraversal t, Node n) {
Node target = n.getFirstChild();
return (isAssignTarget(n) || isTypedefTarget(n)) && isGoogModuleExportsRef(t, target);
}
private static boolean isAssignTarget(Node n) {
Node parent = n.getParent();
return parent.isAssign() && parent.getFirstChild() == n;
}
private static boolean isTypedefTarget(Node n) {
Node parent = n.getParent();
return parent.isExprResult() && parent.getFirstChild() == n;
}
/**
* Add alias nodes to the symbol table as they going to be removed by rewriter. Example aliases:
*
*
const Foo = goog.require('my.project.Foo'); const bar = goog.require('my.project.baz');
* const {baz} = goog.require('my.project.utils');
*/
private void maybeAddAliasToSymbolTable(Node n, String module) {
if (preprocessorSymbolTable != null) {
n.putBooleanProp(Node.MODULE_ALIAS, true);
// Alias can be used in js types. Types have node type STRING and not NAME so we have to
// use their name as string.
String nodeName =
n.isStringLit() ? n.getString() : preprocessorSymbolTable.getQualifiedName(n);
// We need to include module as part of the name because aliases are local to current module.
// Aliases with the same name from different module should be completely different entities.
String name = "alias_" + module + "_" + nodeName;
preprocessorSymbolTable.addReference(n, name);
}
}
private void declareGlobalVariable(Node n, NodeTraversal t) {
checkState(n.isName());
if (this.globalTypedScope == null) {
return;
}
String name = n.getString();
if (this.globalTypedScope.hasOwnSlot(name)) {
t.report(t.getCurrentScript(), ILLEGAL_MODULE_RENAMING_CONFLICT, name);
} else {
JSType type = checkNotNull(n.getJSType());
this.globalTypedScope.declare(name, n, type, t.getInput(), false);
}
}
}