com.google.javascript.jscomp.ModuleRenaming Maven / Gradle / Ivy
/*
* Copyright 2018 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.checkState;
import com.google.common.base.Joiner;
import com.google.javascript.jscomp.modules.Binding;
import com.google.javascript.jscomp.modules.Export;
import com.google.javascript.jscomp.modules.Module;
import com.google.javascript.jscomp.modules.ModuleMap;
import com.google.javascript.jscomp.modules.ModuleMetadataMap.ModuleMetadata;
import com.google.javascript.rhino.Node;
import java.util.List;
import javax.annotation.Nullable;
/** Centralized location for determining how to rename modules. */
final class ModuleRenaming {
private ModuleRenaming() {}
/**
* The name of the temporary variable created for the default export before globalization of the
* module.
*/
static final String DEFAULT_EXPORT_VAR_PREFIX = "$jscompDefaultExport";
/** Returns the global name of a variable declared in an ES module. */
static String getGlobalNameOfEsModuleLocalVariable(
ModuleMetadata moduleMetadata, String variableName) {
return variableName + "$$" + getGlobalName(moduleMetadata, /* googNamespace= */ null);
}
/** Returns the global name of the anonymous default export for the given module. */
static String getGlobalNameOfAnonymousDefaultExport(ModuleMetadata moduleMetadata) {
return getGlobalNameOfEsModuleLocalVariable(moduleMetadata, DEFAULT_EXPORT_VAR_PREFIX);
}
/**
* @param moduleMetadata the metadata of the module to get the global name of
* @param googNamespace the Closure namespace that is being referenced fromEsModule this module,
* if any
* @return the global, qualified name to rewrite any references to this module to
*/
static String getGlobalName(ModuleMetadata moduleMetadata, @Nullable String googNamespace) {
checkState(googNamespace == null || moduleMetadata.googNamespaces().contains(googNamespace));
switch (moduleMetadata.moduleType()) {
case GOOG_MODULE:
return ClosureRewriteModule.getBinaryModuleNamespace(googNamespace);
case GOOG_PROVIDE:
case LEGACY_GOOG_MODULE:
return googNamespace;
case ES6_MODULE:
case COMMON_JS:
return moduleMetadata.path().toModuleName();
case SCRIPT:
// fall through, throw an error
}
throw new IllegalStateException("Unexpected module type: " + moduleMetadata.moduleType());
}
/** Returns the post-transpilation, globalized name of the export. */
static String getGlobalName(Export export) {
if (export.moduleMetadata().isEs6Module()) {
if (export.localName().equals(Export.DEFAULT_EXPORT_NAME)) {
return getGlobalNameOfAnonymousDefaultExport(export.moduleMetadata());
}
return getGlobalNameOfEsModuleLocalVariable(export.moduleMetadata(), export.localName());
}
return getGlobalName(export.moduleMetadata(), export.closureNamespace())
+ "."
+ export.exportName();
}
/** Returns the post-transpilation, globalized name of the binding. */
static String getGlobalName(Binding binding) {
if (binding.isModuleNamespace()) {
return getGlobalName(binding.metadata(), binding.closureNamespace());
}
return getGlobalName(binding.originatingExport());
}
/**
* Returns the globalized name of a reference to a binding in JS Doc. See {@link
* #replace(AbstractCompiler, ModuleMap, Binding, Node)} to replace actual code nodes.
*
* For example:
*
*
* // bar
* export class Bar {}
*
*
*
* // foo
* import * as bar from 'bar';
* export {bar};
*
*
*
* import * as foo from 'foo';
* let /** !foo.bar.Bar *\/ b;
*
*
* Should call this method with the binding for {@code foo} and a list ("bar", "Bar"). In this
* example any of these properties could also be modules. This method will replace as much as the
* GETPROP as it can with module exported variables. Meaning in the above example this would
* return something like "baz$$module$bar", whereas if this method were called for just "foo.bar"
* it would return "module$bar", as it refers to a module object itself.
*/
static String getGlobalNameForJsDoc(
ModuleMap moduleMap, Binding binding, List propertyChain) {
int prop = 0;
while (binding.isModuleNamespace()
&& binding.metadata().isEs6Module()
&& prop < propertyChain.size()) {
String propertyName = propertyChain.get(prop);
Module m = moduleMap.getModule(binding.metadata().path());
if (m.namespace().containsKey(propertyName)) {
binding = m.namespace().get(propertyName);
} else {
// This means someone referenced an invalid export on a module object. This should be an
// error, so just rewrite and let the type checker complain later. It isn't a super clear
// error, but we're working on type checking modules soon.
break;
}
prop++;
}
String globalName = getGlobalName(binding);
if (prop < propertyChain.size()) {
globalName =
globalName + "." + Joiner.on('.').join(propertyChain.subList(prop, propertyChain.size()));
}
return globalName;
}
/**
* Replaces the reference to a given binding. See {@link #getGlobalNameForJsDoc(ModuleMap,
* Binding, List)} for a JS Doc version.
*
* For example:
*
*
* // bar
* export let baz = {qux: 0};
*
*
*
* // foo
* import * as bar from 'bar';
* export {bar};
*
*
*
* import * as foo from 'foo';
* use(foo.bar.baz.qux);
*
*
* Should call this method with the binding and node for {@code foo}. In this example any of
* these properties could also be modules. This method will replace as much as the GETPROP as it
* can with module exported variables. Meaning in the above example this would return something
* like "baz$$module$bar.qux", whereas if this method were called for just "foo.bar" it would
* return "module$bar", as it refers to a module object itself.
*
* @param binding the binding nameNode is a reference to
* @param nameNode the node to replace
*/
static Node replace(
AbstractCompiler compiler, ModuleMap moduleMap, Binding binding, Node nameNode) {
checkState(nameNode.isName());
Node n = nameNode;
while (binding.isModuleNamespace()
&& binding.metadata().isEs6Module()
&& n.getParent().isGetProp()) {
String propertyName = n.getParent().getSecondChild().getString();
Module m = moduleMap.getModule(binding.metadata().path());
if (m.namespace().containsKey(propertyName)) {
binding = m.namespace().get(propertyName);
n = n.getParent();
} else {
// This means someone referenced an invalid export on a module object. This should be an
// error, so just rewrite and let the type checker complain later. It isn't a super clear
// error, but we're working on type checking modules soon.
break;
}
}
String globalName = getGlobalName(binding);
Node newNode = NodeUtil.newQName(compiler, globalName);
// For kythe: the new node only represents the last name it replaced, not all the names.
// e.g. if we rewrite `a.b.c.d.e` to `x.d.e`, then `x` should map to `c`, not `a.b.c`.
Node forSourceInfo = n.isGetProp() ? n.getSecondChild() : n;
n.replaceWith(newNode);
newNode.srcrefTree(forSourceInfo);
newNode.setOriginalName(forSourceInfo.getString());
return newNode;
}
}