Package com.google.javascript.jscomp

Class RewritePolyfills

java.lang.Object

com.google.javascript.jscomp.RewritePolyfills

All Implemented Interfaces:

CompilerPass

public class RewritePolyfills
extends Object
implements CompilerPass

Injects polyfill libraries to ensure that ES6+ library functions are available.

Also runs if polyfill isolation is enabled, even if polyfill injection is disabled, in order to prevent deletion of a required library function by dead code elimination.

TODO(b/120486392): consider merging this pass with InjectRuntimeLibraries and InjectTranspilationRuntimeLibraries.

Constructor Summary

Constructors

Constructor	Description
RewritePolyfills(AbstractCompiler compiler, boolean injectPolyfills, boolean isolatePolyfills, CompilerOptions.LanguageMode injectPolyfillsNewerThan)

Method Summary

Modifier and Type	Method	Description
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 Details

RewritePolyfills

public RewritePolyfills(AbstractCompiler compiler,
 boolean injectPolyfills,
 boolean isolatePolyfills,
 CompilerOptions.LanguageMode injectPolyfillsNewerThan)

Parameters:

injectPolyfills - if true, injects $jscomp.polyfill initializations into the first input. if false, no polyfills are injected.

isolatePolyfills - if true, adds externs for library functions used by IsolatePolyfills to prevent their deletion.

Method Details

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