com.google.javascript.jscomp

Class InjectTranspilationRuntimeLibraries

java.lang.Object

com.google.javascript.jscomp.NodeTraversal.AbstractPostOrderCallback

com.google.javascript.jscomp.InjectTranspilationRuntimeLibraries

All Implemented Interfaces:

CompilerPass, HotSwapCompilerPass, NodeTraversal.Callback

public final class InjectTranspilationRuntimeLibraries
extends NodeTraversal.AbstractPostOrderCallback
implements HotSwapCompilerPass

Injects JS library code that may be needed by the transpiled form of the input source code.

The intention here is to add anything that could be needed and rely on RemoveUnusedCode to remove the parts that don't end up getting used. This pass should run before type checking so the type checking code can add type information to the injected JavaScript for checking and optimization purposes.

This class also reports an error if it finds getters or setters are used and the language output level is too low to support them. TODO(bradfordcsmith): The getter/setter check should probably be done separately in an earlier pass that only runs when the output language level is ES3 and the input language level is ES5 or greater.

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

Constructor Summary

Constructors

Constructor and Description
InjectTranspilationRuntimeLibraries(AbstractCompiler compiler)

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.
void	visit(NodeTraversal t, Node n, Node parent) Visits a node in postorder (after its children).

Methods inherited from class com.google.javascript.jscomp.NodeTraversal.AbstractPostOrderCallback

shouldTraverse

Methods inherited from class java.lang.Object

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

Constructor Detail

InjectTranspilationRuntimeLibraries

public InjectTranspilationRuntimeLibraries(AbstractCompiler compiler)

Method Detail

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

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.

visit

public void visit(NodeTraversal t,
                  Node n,
                  Node parent)

Description copied from interface: NodeTraversal.Callback

Visits a node in postorder (after its children). A node is visited in postorder iff NodeTraversal.Callback.shouldTraverse(NodeTraversal, Node, Node) returned true for its parent. In particular, the root node is never visited in postorder.

Siblings are always visited left-to-right.

Implementations can have side-effects (e.g. modify the parse tree). Removing the current node is legal, but removing or reordering nodes above the current node may cause nodes to be visited twice or not at all.

Specified by:

visit in interface NodeTraversal.Callback

Parameters:

t - The current traversal.

n - The current node.

parent - The parent of the current node.