com.google.javascript.jscomp

Class RewriteGoogJsImports

java.lang.Object

com.google.javascript.jscomp.RewriteGoogJsImports

All Implemented Interfaces:

CompilerPass, HotSwapCompilerPass

public class RewriteGoogJsImports
extends java.lang.Object
implements HotSwapCompilerPass

Looks for references to Closure's goog.js file and globalizes. The goog.js file is an ES6 module that forwards some symbols on goog from Closure's base.js file, like require.

This pass scans the goog.js file to find what keys are exported. When rewriting imports only those in the goog.js file are globalized; if there is a reference to something not in the goog.js file it is rewritten in such a way to cause an error later at type checking.

This is a separate pass that needs to run before Es6RewriteModules which will remove import statements.

This pass enforces the following so that later compiler passes and regex based tools can correctly recognize references to these properties of goog (like goog.require):

• No other file is named goog.js
• The file is always imported as import * as goog
• No other module level variable is named goog
• export from is never used on goog.js

Example:

import * as goog from 'path/to/closure/goog.js'; const myNamespace = goog.require('my.namespace');

Will be rewritten to:

import 'path/to/closure/goog.js'; const myNamespace = goog.require('my.namespace');

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RewriteGoogJsImports.Mode Possible traversal modes - either linting or linting+rewriting.

Constructor Summary

Constructors

Constructor and Description
RewriteGoogJsImports(AbstractCompiler compiler, RewriteGoogJsImports.Mode mode, ModuleMap moduleMap)

Method Summary

Modifier and Type	Method and Description
void	hotSwapScript(Node scriptRoot, Node originalRoot) Process the JS with root node root.
void	process(Node externs, Node root) Process the JS with root node root.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RewriteGoogJsImports

public RewriteGoogJsImports(AbstractCompiler compiler,
                            RewriteGoogJsImports.Mode mode,
                            ModuleMap moduleMap)

Method Detail

hotSwapScript

public void hotSwapScript(Node scriptRoot,
                          Node originalRoot)

Description copied from interface: HotSwapCompilerPass

Process the JS with root node root. This is supposed to be significantly faster compared to corresponding full-compiler passes.

Specified by:

hotSwapScript in interface HotSwapCompilerPass

Parameters:

scriptRoot - Root node corresponding to the file that is modified, should be of type Token.SCRIPT.

originalRoot - Root node corresponding to the original version of the file that is modified. Should be of type token.SCRIPT.

process

public void process(Node externs,
                    Node root)

Description copied from interface: CompilerPass

Process the JS with root node root. Can modify the contents of each Node tree

Specified by:

process in interface CompilerPass

Parameters:

externs - Top of external JS tree

root - Top of JS tree