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ProcessCommonJSModules.java
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ProcessCommonJSModules.java
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/*
* Copyright 2011 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.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
import com.google.common.base.Predicate;
import com.google.common.base.Predicates;
import com.google.common.collect.ImmutableCollection;
import com.google.common.collect.ImmutableList;
import com.google.javascript.jscomp.NodeTraversal.AbstractPostOrderCallback;
import com.google.javascript.jscomp.deps.ModuleLoader;
import com.google.javascript.jscomp.deps.ModuleLoader.ModulePath;
import com.google.javascript.rhino.IR;
import com.google.javascript.rhino.JSDocInfo;
import com.google.javascript.rhino.JSDocInfoBuilder;
import com.google.javascript.rhino.Node;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;
/**
* Rewrites a CommonJS module http://wiki.commonjs.org/wiki/Modules/1.1.1 into a form that can be
* safely concatenated. Does not add a function around the module body but instead adds suffixes to
* global variables to avoid conflicts. Calls to require are changed to reference the required
* module directly.
*/
public final class ProcessCommonJSModules extends NodeTraversal.AbstractPreOrderCallback
implements CompilerPass {
private static final String EXPORTS = "exports";
private static final String MODULE = "module";
private static final String REQUIRE = "require";
private static final String EXPORT_PROPERTY_NAME = "default";
public static final DiagnosticType UNKNOWN_REQUIRE_ENSURE =
DiagnosticType.warning(
"JSC_COMMONJS_UNKNOWN_REQUIRE_ENSURE_ERROR", "Unrecognized require.ensure call: {0}");
public static final DiagnosticType SUSPICIOUS_EXPORTS_ASSIGNMENT =
DiagnosticType.warning(
"JSC_COMMONJS_SUSPICIOUS_EXPORTS_ASSIGNMENT",
"Suspicious re-assignment of \"exports\" variable."
+ " Did you actually intend to export something?");
private final AbstractCompiler compiler;
/**
* Creates a new ProcessCommonJSModules instance which can be used to rewrite CommonJS modules to
* a concatenable form.
*
* @param compiler The compiler
*/
public ProcessCommonJSModules(AbstractCompiler compiler) {
this.compiler = compiler;
}
@Override
public void process(Node externs, Node root) {
NodeTraversal.traverseEs6(compiler, root, this);
}
@Override
public boolean shouldTraverse(NodeTraversal t, Node n, Node parent) {
if (n.isRoot()) {
return true;
} else if (n.isScript()) {
FindImportsAndExports finder = new FindImportsAndExports();
NodeTraversal.traverseEs6(compiler, n, finder);
CompilerInput.ModuleType moduleType = compiler.getInput(n.getInputId()).getJsModuleType();
boolean forceModuleDetection = moduleType == CompilerInput.ModuleType.IMPORTED_SCRIPT;
boolean defaultExportIsConst = true;
boolean isCommonJsModule = finder.isCommonJsModule();
ImmutableList.Builder<ExportInfo> exports = ImmutableList.builder();
boolean needsRetraverse = false;
if (isCommonJsModule || forceModuleDetection) {
finder.reportModuleErrors();
if (!finder.umdPatterns.isEmpty()) {
if (finder.replaceUmdPatterns()) {
needsRetraverse = true;
}
// Removing the IIFE rewrites vars. We need to re-traverse
// to get the new references.
if (removeIIFEWrapper(n)) {
needsRetraverse = true;
}
if (needsRetraverse) {
finder = new FindImportsAndExports();
NodeTraversal.traverseEs6(compiler, n, finder);
}
}
defaultExportIsConst = finder.initializeModule();
//UMD pattern replacement can leave detached export references - don't include those
for (ExportInfo export : finder.getModuleExports()) {
if (NodeUtil.getEnclosingScript(export.node) != null) {
exports.add(export);
}
}
for (ExportInfo export : finder.getExports()) {
if (NodeUtil.getEnclosingScript(export.node) != null) {
exports.add(export);
}
}
} else if (needsRetraverse) {
finder = new FindImportsAndExports();
NodeTraversal.traverseEs6(compiler, n, finder);
}
NodeTraversal.traverseEs6(
compiler,
n,
new RewriteModule(
isCommonJsModule || forceModuleDetection, exports.build(), defaultExportIsConst));
}
return false;
}
public static String getModuleName(CompilerInput input) {
ModulePath modulePath = input.getPath();
if (modulePath == null) {
return null;
}
return getModuleName(modulePath);
}
public static String getModuleName(ModulePath input) {
return input.toModuleName();
}
public String getBasePropertyImport(String moduleName) {
CompilerInput.ModuleType moduleType = compiler.getModuleTypeByName(moduleName);
if (moduleType != null && moduleType != CompilerInput.ModuleType.COMMONJS) {
return moduleName;
}
return moduleName + "." + EXPORT_PROPERTY_NAME;
}
/**
* Recognize if a node is a module import. We recognize the form:
*
* <ul>
* <li>require("something");
* </ul>
*/
public static boolean isCommonJsImport(Node requireCall) {
if (requireCall.isCall() && requireCall.hasTwoChildren()) {
if (requireCall.getFirstChild().matchesQualifiedName(REQUIRE)
&& requireCall.getSecondChild().isString()) {
return true;
}
}
return false;
}
public static String getCommonJsImportPath(Node requireCall) {
return requireCall.getSecondChild().getString();
}
private String getImportedModuleName(NodeTraversal t, Node requireCall) {
return getImportedModuleName(t, requireCall, getCommonJsImportPath(requireCall));
}
private String getImportedModuleName(NodeTraversal t, Node n, String importPath) {
ModulePath modulePath =
t.getInput()
.getPath()
.resolveJsModule(importPath, n.getSourceFileName(), n.getLineno(), n.getCharno());
if (modulePath == null) {
return ModuleIdentifier.forFile(importPath).getModuleName();
}
return modulePath.toModuleName();
}
/**
* Recognize if a node is a module export. We recognize several forms:
*
* <ul>
* <li> module.exports = something;
* <li> module.exports.something = something;
* <li> exports.something = something;
* </ul>
*
* <p>In addition, we only recognize an export if the base export object is not defined or is
* defined in externs.
*/
public static boolean isCommonJsExport(NodeTraversal t, Node export) {
if (export.matchesQualifiedName(MODULE + "." + EXPORTS)) {
Var v = t.getScope().getVar(MODULE);
if (v == null || v.isExtern()) {
return true;
}
} else if (export.isName() && EXPORTS.equals(export.getString())) {
Var v = t.getScope().getVar(export.getString());
if (v == null || v.isGlobal()) {
return true;
}
}
return false;
}
/**
* Information on a Universal Module Definition A UMD is an IF statement and a reference to which
* branch contains the commonjs export
*/
static class UmdPattern {
final Node ifRoot;
final Node activeBranch;
UmdPattern(Node ifRoot, Node activeBranch) {
this.ifRoot = ifRoot;
this.activeBranch = activeBranch;
}
}
static class ExportInfo {
final Node node;
final Scope scope;
ExportInfo(Node node, Scope scope) {
this.node = node;
this.scope = scope;
}
}
private Node getBaseQualifiedNameNode(Node n) {
Node refParent = n;
while (refParent.getParent() != null && refParent.getParent().isQualifiedName()) {
refParent = refParent.getParent();
}
return refParent;
}
/**
* UMD modules are often wrapped in an IIFE for cases where they are used as scripts instead of
* modules. Remove the wrapper.
* @return Whether an IIFE wrapper was found and removed.
*/
private boolean removeIIFEWrapper(Node root) {
checkState(root.isScript());
Node n = root.getFirstChild();
// Sometimes scripts start with a semicolon for easy concatenation.
// Skip any empty statements from those
while (n != null && n.isEmpty()) {
n = n.getNext();
}
// An IIFE wrapper must be the only non-empty statement in the script,
// and it must be an expression statement.
if (n == null || !n.isExprResult() || n.getNext() != null) {
return false;
}
// Function expression can be forced with !, just skip !
// TODO(ChadKillingsworth):
// Expression could also be forced with: + - ~ void
// ! ~ void can be repeated any number of times
if (n != null && n.getFirstChild() != null && n.getFirstChild().isNot()) {
n = n.getFirstChild();
}
Node call = n.getFirstChild();
if (call == null || !call.isCall()) {
return false;
}
// Find the IIFE call and function nodes
Node fnc;
if (call.getFirstChild().isFunction()) {
fnc = n.getFirstFirstChild();
} else if (call.getFirstChild().isGetProp()
&& call.getFirstFirstChild().isFunction()
&& call.getFirstFirstChild().getNext().isString()
&& call.getFirstFirstChild().getNext().getString().equals("call")) {
fnc = call.getFirstFirstChild();
// We only support explicitly binding "this" to the parent "this" or "exports"
if (!(call.getSecondChild() != null
&& (call.getSecondChild().isThis()
|| call.getSecondChild().matchesQualifiedName(EXPORTS)))) {
return false;
}
} else {
return false;
}
if (NodeUtil.doesFunctionReferenceOwnArgumentsObject(fnc)) {
return false;
}
CompilerInput ci = compiler.getInput(root.getInputId());
ModulePath modulePath = ci.getPath();
if (modulePath == null) {
return false;
}
String iifeLabel = getModuleName(modulePath) + "_iifeWrapper";
FunctionToBlockMutator mutator =
new FunctionToBlockMutator(compiler, compiler.getUniqueNameIdSupplier());
Node block = mutator.mutateWithoutRenaming(iifeLabel, fnc, call, null, false, false);
root.removeChildren();
root.addChildrenToFront(block.removeChildren());
reportNestedScopesDeleted(fnc);
compiler.reportChangeToEnclosingScope(root);
return true;
}
/**
* Traverse the script. Find all references to CommonJS require (import) and module.exports or
* export statements. Rewrites any require calls to reference the rewritten module name.
*/
class FindImportsAndExports implements NodeTraversal.Callback {
private boolean hasGoogProvideOrModule = false;
private Node script = null;
boolean isCommonJsModule() {
return (exports.size() > 0 || moduleExports.size() > 0) && !hasGoogProvideOrModule;
}
List<UmdPattern> umdPatterns = new ArrayList<>();
List<ExportInfo> moduleExports = new ArrayList<>();
List<ExportInfo> exports = new ArrayList<>();
List<JSError> errors = new ArrayList<>();
public List<ExportInfo> getModuleExports() {
return ImmutableList.copyOf(moduleExports);
}
public List<ExportInfo> getExports() {
return ImmutableList.copyOf(exports);
}
@Override
public boolean shouldTraverse(NodeTraversal nodeTraversal, Node n, Node parent) {
if (n.isScript()) {
checkState(this.script == null);
this.script = n;
}
return true;
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
if (t.inGlobalScope()) {
// Check for goog.provide or goog.module statements
if (parent == null
|| NodeUtil.isControlStructure(parent)
|| NodeUtil.isStatementBlock(parent)) {
if (n.isExprResult()) {
Node maybeGetProp = n.getFirstFirstChild();
if (maybeGetProp != null
&& (maybeGetProp.matchesQualifiedName("goog.provide")
|| maybeGetProp.matchesQualifiedName("goog.module"))) {
hasGoogProvideOrModule = true;
}
}
}
}
// Find require.ensure calls
if (n.isCall() && n.getFirstChild().matchesQualifiedName("require.ensure")) {
visitRequireEnsureCall(t, n);
}
if (n.matchesQualifiedName(MODULE + "." + EXPORTS)) {
if (isCommonJsExport(t, n)) {
moduleExports.add(new ExportInfo(n, t.getScope()));
// If the module.exports statement is nested in the then branch of an if statement,
// assume the if statement is an UMD pattern with a common js export in the then branch
// This seems fragile but has worked well for a long time.
// TODO(ChadKillingsworth): Discover if there is a better way to detect these.
Node ifAncestor = getOutermostIfAncestor(parent);
if (ifAncestor != null && (NodeUtil.isLValue(n) || isInIfTest(n))) {
UmdPattern existingPattern = findUmdPattern(umdPatterns, ifAncestor);
if (existingPattern != null) {
umdPatterns.remove(existingPattern);
}
Node enclosingIf =
NodeUtil.getEnclosingNode(
n,
new Predicate<Node>() {
@Override
public boolean apply(Node node) {
return node.isIf() || node.isHook();
}
});
umdPatterns.add(new UmdPattern(ifAncestor, enclosingIf.getSecondChild()));
}
}
} else if (n.matchesQualifiedName("define.amd")) {
// If a define.amd statement is nested in the then branch of an if statement,
// assume the if statement is an UMD pattern with a common js export
// in the else branch
// This seems fragile but has worked well for a long time.
// TODO(ChadKillingsworth): Discover if there is a better way to detect these.
Node ifAncestor = getOutermostIfAncestor(parent);
if (ifAncestor != null
&& findUmdPattern(umdPatterns, ifAncestor) == null
&& (NodeUtil.isLValue(n) || isInIfTest(n))) {
umdPatterns.add(new UmdPattern(ifAncestor, ifAncestor.getChildAtIndex(2)));
}
}
if (n.isName() && EXPORTS.equals(n.getString())) {
Var v = t.getScope().getVar(EXPORTS);
if (v == null || v.isGlobal()) {
Node qNameRoot = getBaseQualifiedNameNode(n);
if (qNameRoot != null
&& qNameRoot.matchesQualifiedName(EXPORTS)
&& NodeUtil.isLValue(qNameRoot)) {
// Match the special assignment
// exports = module.exports
if (n.getGrandparent().isExprResult()
&& n.getNext() != null
&& ((n.getNext().isGetProp()
&& n.getNext().matchesQualifiedName(MODULE + "." + EXPORTS))
|| (n.getNext().isAssign()
&& n.getNext()
.getFirstChild()
.matchesQualifiedName(MODULE + "." + EXPORTS)))) {
exports.add(new ExportInfo(n, t.getScope()));
} else if (!this.hasGoogProvideOrModule) {
errors.add(t.makeError(qNameRoot, SUSPICIOUS_EXPORTS_ASSIGNMENT));
}
} else {
exports.add(new ExportInfo(n, t.getScope()));
// If the exports statement is nested in the then branch of an if statement,
// assume the if statement is an UMD pattern with a common js export in the then branch
// This seems fragile but has worked well for a long time.
// TODO(ChadKillingsworth): Discover if there is a better way to detect these.
Node ifAncestor = getOutermostIfAncestor(parent);
if (ifAncestor != null
&& findUmdPattern(umdPatterns, ifAncestor) == null
&& (NodeUtil.isLValue(n) || isInIfTest(n))) {
umdPatterns.add(new UmdPattern(ifAncestor, ifAncestor.getSecondChild()));
}
}
}
} else if (n.isThis() && n.getParent().isGetProp() && t.inGlobalScope()) {
exports.add(new ExportInfo(n, t.getScope()));
}
if (ProcessCommonJSModules.isCommonJsImport(n)) {
visitRequireCall(t, n, parent);
}
}
/** Visit require calls. */
private void visitRequireCall(NodeTraversal t, Node require, Node parent) {
// When require("name") is used as a standalone statement (the result isn't used)
// it indicates that a module is being loaded for the side effects it produces.
// In this case the require statement should just be removed as the dependency
// sorting will insert the file for us.
if (!NodeUtil.isExpressionResultUsed(require)
&& parent.isExprResult()
&& NodeUtil.isStatementBlock(parent.getParent())) {
// Attempt to resolve the module so that load warnings are issued
t.getInput()
.getPath()
.resolveJsModule(
getCommonJsImportPath(require),
require.getSourceFileName(),
require.getLineno(),
require.getCharno());
Node grandparent = parent.getParent();
parent.detach();
compiler.reportChangeToEnclosingScope(grandparent);
}
}
/**
* Visit require.ensure calls. Replace the call with an IIFE. Require.ensure must always be of
* the form:
*
* <p>require.ensure(['module1', ...], function(require) {})
*/
private void visitRequireEnsureCall(NodeTraversal t, Node call) {
if (call.getChildCount() != 3) {
compiler.report(
t.makeError(
call,
UNKNOWN_REQUIRE_ENSURE,
"Expected the function to have 2 arguments but instead found {0}",
"" + call.getChildCount()));
return;
}
Node dependencies = call.getSecondChild();
if (!dependencies.isArrayLit()) {
compiler.report(
t.makeError(
dependencies,
UNKNOWN_REQUIRE_ENSURE,
"The first argument must be an array literal of string literals."));
return;
}
for (Node dep : dependencies.children()) {
if (!dep.isString()) {
compiler.report(
t.makeError(
dep,
UNKNOWN_REQUIRE_ENSURE,
"The first argument must be an array literal of string literals."));
return;
}
}
Node callback = dependencies.getNext();
if (!(callback.isFunction()
&& callback.getSecondChild().getChildCount() == 1
&& callback.getSecondChild().getFirstChild().isName()
&& "require".equals(callback.getSecondChild().getFirstChild().getString()))) {
compiler.report(
t.makeError(
callback,
UNKNOWN_REQUIRE_ENSURE,
"The second argument must be a function"
+ " whose first argument is named \"require\"."));
return;
}
callback.detach();
// Remove the "require" argument from the parameter list.
callback.getSecondChild().removeChildren();
call.removeChildren();
call.putBooleanProp(Node.FREE_CALL, true);
call.addChildToFront(callback);
t.reportCodeChange();
}
void reportModuleErrors() {
for (JSError error : errors) {
compiler.report(error);
}
}
/**
* If the export is directly assigned more than once, or the assignments are not global, declare
* the module name variable.
*
* <p>If all of the assignments are simply property assignments, initialize the module name
* variable as a namespace.
*
* <p>Returns whether the default export can be declared constant
*/
boolean initializeModule() {
CompilerInput ci = compiler.getInput(this.script.getInputId());
ModulePath modulePath = ci.getPath();
if (modulePath == null) {
return true;
}
String moduleName = getModuleName(ci);
List<ExportInfo> exportsToRemove = new ArrayList<>();
for (ExportInfo export : exports) {
if (NodeUtil.getEnclosingScript(export.node) == null) {
continue;
}
Node qNameBase = getBaseQualifiedNameNode(export.node);
if (export.node == qNameBase
&& export.node.getParent().isAssign()
&& export.node.getGrandparent().isExprResult()
&& export.node.getPrevious() == null
&& export.node.getNext() != null) {
// Find any identity assignments and just remove them
// exports = module.exports;
if (export.node.getNext().isGetProp()
&& export.node.getNext().matchesQualifiedName(MODULE + "." + EXPORTS)) {
for (ExportInfo moduleExport : moduleExports) {
if (moduleExport.node == export.node.getNext()) {
moduleExports.remove(moduleExport);
break;
}
}
Node changeRoot = export.node.getGrandparent().getParent();
export.node.getGrandparent().detach();
exportsToRemove.add(export);
compiler.reportChangeToEnclosingScope(changeRoot);
// Find compound identity assignments and remove the exports = portion
// exports = module.exports = foo;
} else if (export.node.getNext().isAssign()
&& export
.node
.getNext()
.getFirstChild()
.matchesQualifiedName(MODULE + "." + EXPORTS)) {
Node assign = export.node.getNext();
export.node.getParent().replaceWith(assign.detach());
exportsToRemove.add(export);
compiler.reportChangeToEnclosingScope(assign);
}
}
}
exports.removeAll(exportsToRemove);
// If we assign to the variable more than once or all the assignments
// are properties, initialize the variable as well.
int directAssignments = 0;
for (ExportInfo export : moduleExports) {
if (NodeUtil.getEnclosingScript(export.node) == null) {
continue;
}
Node base = getBaseQualifiedNameNode(export.node);
if (base == export.node && export.node.getParent().isAssign()) {
Node rValue = NodeUtil.getRValueOfLValue(export.node);
if (rValue == null || !rValue.isObjectLit()) {
directAssignments++;
}
}
}
Node initModule = IR.var(IR.name(moduleName), IR.objectlit());
initModule.getFirstChild().putBooleanProp(Node.MODULE_EXPORT, true);
JSDocInfoBuilder builder = new JSDocInfoBuilder(true);
builder.recordConstancy();
initModule.setJSDocInfo(builder.build());
if (directAssignments == 0) {
Node defaultProp = IR.stringKey(EXPORT_PROPERTY_NAME);
defaultProp.putBooleanProp(Node.MODULE_EXPORT, true);
defaultProp.addChildToFront(IR.objectlit());
initModule.getFirstFirstChild().addChildToFront(defaultProp);
builder = new JSDocInfoBuilder(true);
builder.recordConstancy();
defaultProp.setJSDocInfo(builder.build());
}
this.script.addChildToFront(initModule.useSourceInfoFromForTree(this.script));
compiler.reportChangeToEnclosingScope(this.script);
return directAssignments < 2;
}
/** Find the outermost if node ancestor for a node without leaving the function scope */
private Node getOutermostIfAncestor(Node n) {
if (n == null || NodeUtil.isTopLevel(n) || n.isFunction()) {
return null;
}
Node parent = n.getParent();
if (parent == null) {
return null;
}
// When walking up ternary operations (hook), don't check if parent is the condition,
// because one ternary operation can be then/else branch of another.
if (parent.isIf() || parent.isHook()) {
Node outerIf = getOutermostIfAncestor(parent);
if (outerIf != null) {
return outerIf;
}
return parent;
}
return getOutermostIfAncestor(parent);
}
/** Return whether the node is within the test portion of an if statement */
private boolean isInIfTest(Node n) {
if (n == null || NodeUtil.isTopLevel(n) || n.isFunction()) {
return false;
}
Node parent = n.getParent();
if (parent == null) {
return false;
}
if ((parent.isIf() || parent.isHook()) && parent.getFirstChild() == n) {
return true;
}
return isInIfTest(parent);
}
/** Remove a Universal Module Definition and leave just the commonjs export statement */
boolean replaceUmdPatterns() {
boolean needsRetraverse = false;
Node changeScope;
for (UmdPattern umdPattern : umdPatterns) {
if (NodeUtil.getEnclosingScript(umdPattern.ifRoot) == null) {
reportNestedScopesDeleted(umdPattern.ifRoot);
continue;
}
Node parent = umdPattern.ifRoot.getParent();
Node newNode = umdPattern.activeBranch;
if (newNode == null) {
parent.removeChild(umdPattern.ifRoot);
reportNestedScopesDeleted(umdPattern.ifRoot);
compiler.reportChangeToEnclosingScope(parent);
needsRetraverse = true;
continue;
}
// Remove redundant block node. Not strictly necessary, but makes tests more legible.
if (umdPattern.activeBranch.isNormalBlock()
&& umdPattern.activeBranch.getChildCount() == 1) {
newNode = umdPattern.activeBranch.removeFirstChild();
} else {
newNode.detach();
}
needsRetraverse = true;
parent.replaceChild(umdPattern.ifRoot, newNode);
reportNestedScopesDeleted(umdPattern.ifRoot);
changeScope = NodeUtil.getEnclosingChangeScopeRoot(newNode);
if (changeScope != null) {
compiler.reportChangeToEnclosingScope(newNode);
}
Node block = parent;
if (block.isExprResult()) {
block = block.getParent();
}
// Detect UMD Factory Patterns and inline the functions
if (block.isNormalBlock() && block.getParent().isFunction()
&& block.getGrandparent().isCall()
&& parent.hasOneChild()) {
Node enclosingFnCall = block.getGrandparent();
Node fn = block.getParent();
Node enclosingScript = NodeUtil.getEnclosingScript(enclosingFnCall);
if (enclosingScript == null) {
continue;
}
CompilerInput ci = compiler.getInput(
NodeUtil.getEnclosingScript(enclosingFnCall).getInputId());
ModulePath modulePath = ci.getPath();
if (modulePath == null) {
continue;
}
needsRetraverse = true;
String factoryLabel =
modulePath.toModuleName() + "_factory" + compiler.getUniqueNameIdSupplier().get();
FunctionToBlockMutator mutator =
new FunctionToBlockMutator(compiler, compiler.getUniqueNameIdSupplier());
Node newStatements =
mutator.mutateWithoutRenaming(factoryLabel, fn, enclosingFnCall, null, false, false);
// Check to see if the returned block is of the form:
// {
// var jscomp$inline = function() {};
// jscomp$inline();
// }
//
// or
//
// {
// var jscomp$inline = function() {};
// module.exports = jscomp$inline();
// }
//
// If so, inline again
if (newStatements.isNormalBlock()
&& newStatements.hasTwoChildren()
&& newStatements.getFirstChild().isVar()
&& newStatements.getFirstFirstChild().hasOneChild()
&& newStatements.getFirstFirstChild().getFirstChild().isFunction()
&& newStatements.getSecondChild().isExprResult()) {
Node inlinedFn = newStatements.getFirstFirstChild().getFirstChild();
Node expr = newStatements.getSecondChild().getFirstChild();
Node call = null;
String assignedName = null;
if (expr.isAssign() && expr.getSecondChild().isCall()) {
call = expr.getSecondChild();
assignedName =
modulePath.toModuleName() + "_iife" + compiler.getUniqueNameIdSupplier().get();
} else if (expr.isCall()) {
call = expr;
}
if (call != null) {
newStatements =
mutator.mutateWithoutRenaming(
factoryLabel, inlinedFn, call, assignedName, false, false);
if (assignedName != null) {
Node newName =
IR.var(
NodeUtil.newName(
compiler,
assignedName,
fn,
expr.getFirstChild().getQualifiedName()))
.useSourceInfoFromForTree(fn);
if (newStatements.hasChildren()
&& newStatements.getFirstChild().isExprResult()
&& newStatements.getFirstFirstChild().isAssign()
&& newStatements.getFirstFirstChild().getFirstChild().isName()
&& newStatements
.getFirstFirstChild()
.getFirstChild()
.getString()
.equals(assignedName)) {
newName
.getFirstChild()
.addChildToFront(
newStatements.getFirstFirstChild().getSecondChild().detach());
newStatements.replaceChild(newStatements.getFirstChild(), newName);
} else {
newStatements.addChildToFront(newName);
}
expr.replaceChild(expr.getSecondChild(), newName.getFirstChild().cloneNode());
newStatements.addChildToBack(expr.getParent().detach());
}
}
}
Node callRoot = enclosingFnCall.getParent();
if (callRoot.isNot()) {
callRoot = callRoot.getParent();
}
if (callRoot.isExprResult()) {
Node callRootParent = callRoot.getParent();
callRootParent.addChildrenAfter(newStatements.removeChildren(), callRoot);
callRoot.detach();
reportNestedScopesChanged(callRootParent);
compiler.reportChangeToEnclosingScope(callRootParent);
reportNestedScopesDeleted(enclosingFnCall);
} else {
parent.replaceChild(umdPattern.ifRoot, newNode);
compiler.reportChangeToEnclosingScope(newNode);
reportNestedScopesDeleted(umdPattern.ifRoot);
}
}
}
return needsRetraverse;
}
}
private void reportNestedScopesDeleted(Node n) {
NodeUtil.visitPreOrder(
n,
new NodeUtil.Visitor() {
@Override
public void visit(Node n) {
if (n.isFunction()) {
compiler.reportFunctionDeleted(n);
}
}
},
Predicates.<Node>alwaysTrue());
}
private void reportNestedScopesChanged(Node n) {
NodeUtil.visitPreOrder(
n,
new NodeUtil.Visitor() {
@Override
public void visit(Node n) {
if (n.isFunction()) {
compiler.reportChangeToChangeScope(n);
}
}
},
Predicates.<Node>alwaysTrue());
}
private static UmdPattern findUmdPattern(List<UmdPattern> umdPatterns, Node n) {
for (UmdPattern umd : umdPatterns) {
if (umd.ifRoot == n) {
return umd;
}
}
return null;
}
/**
* Traverse a file and rewrite all references to imported names directly to the targeted module
* name.
*
* <p>If a file is a CommonJS module, rewrite export statements. Typically exports create an alias
* - the rewriting tries to avoid such aliases.
*/
private class RewriteModule extends AbstractPostOrderCallback {
private final boolean allowFullRewrite;
private final ImmutableCollection<ExportInfo> exports;
private final List<Node> imports = new ArrayList<>();
private final List<Node> rewrittenClassExpressions = new ArrayList<>();
private final List<Node> functionsToHoist = new ArrayList<>();
private final boolean defaultExportIsConst;
public RewriteModule(
boolean allowFullRewrite,
ImmutableCollection<ExportInfo> exports,
boolean defaultExportIsConst) {
this.allowFullRewrite = allowFullRewrite;
this.exports = exports;
this.defaultExportIsConst = defaultExportIsConst;
}
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
switch (n.getToken()) {
case SCRIPT:
// Class names can't be changed during the middle of a traversal. Unlike functions,
// the name can be the EMPTY token rather than just a zero length string.
for (Node clazz : rewrittenClassExpressions) {
clazz.replaceChild(
clazz.getFirstChild(), IR.empty().useSourceInfoFrom(clazz.getFirstChild()));
t.reportCodeChange();
}
CompilerInput ci = compiler.getInput(n.getInputId());
String moduleName = getModuleName(ci);
// If a function is the direct module export, move it to the top.
for (int i = 1; i < functionsToHoist.size(); i++) {
if (functionsToHoist
.get(i)
.getFirstFirstChild()
.matchesQualifiedName(getBasePropertyImport(moduleName))) {
Node fncVar = functionsToHoist.get(i);
functionsToHoist.remove(i);
functionsToHoist.add(0, fncVar);
break;
}
}
// Hoist functions in reverse order so that they maintain the same relative
// order after hoisting.
for (int i = functionsToHoist.size() - 1; i >= 0; i--) {
Node functionExpr = functionsToHoist.get(i);
Node scopeRoot = t.getClosestHoistScopeRoot();
Node insertionPoint = scopeRoot.getFirstChild();
if (insertionPoint == null
|| !(insertionPoint.isVar()
&& insertionPoint.getFirstChild().getString().equals(moduleName))) {
insertionPoint = null;
}
if (insertionPoint == null) {
if (scopeRoot.getFirstChild() != functionExpr) {
scopeRoot.addChildToFront(functionExpr.detach());
}
} else if (insertionPoint != functionExpr && insertionPoint.getNext() != functionExpr) {
scopeRoot.addChildAfter(functionExpr.detach(), insertionPoint);
}
}
for (ExportInfo export : exports) {
visitExport(t, export);
}
for (Node require : imports) {
visitRequireCall(t, require, require.getParent());
}
break;
case CALL:
if (isCommonJsImport(n)) {
imports.add(n);
}
break;
case VAR:
case LET:
case CONST:
// Multiple declarations need split apart so that they can be refactored into
// property assignments or removed altogether.
if (n.hasMoreThanOneChild() && !NodeUtil.isAnyFor(parent)) {
List<Node> vars = splitMultipleDeclarations(n);
t.reportCodeChange();