com.google.javascript.jscomp

Class ProcessDefines.CollectDefines

java.lang.Object

com.google.javascript.jscomp.ProcessDefines.CollectDefines

All Implemented Interfaces:

NodeTraversal.Callback

Enclosing class:

ProcessDefines

private static final class ProcessDefines.CollectDefines
extends java.lang.Object
implements NodeTraversal.Callback

Finds all assignments to @defines, and figures out the last value of the @define.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	ProcessDefines.CollectDefines.RefInfo A simple data structure for associating a Ref with the name that it references.

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Map<java.lang.String,ProcessDefines.DefineInfo>	allDefines
private java.util.Map<Node,ProcessDefines.CollectDefines.RefInfo>	allRefInfo
private java.util.Map<java.lang.String,ProcessDefines.DefineInfo>	assignableDefines
private java.util.Deque<java.lang.Integer>	assignAllowed
private AbstractCompiler	compiler
private Node	lvalueToRemoveLater

Constructor Summary

Constructors

Constructor and Description
CollectDefines(AbstractCompiler compiler, java.util.List<GlobalNamespace.Name> listOfDefines)

Method Summary

Modifier and Type	Method and Description
(package private) java.util.Map<java.lang.String,ProcessDefines.DefineInfo>	getAllDefines() Get a map of ProcessDefines.DefineInfo structures, keyed by the name of the define.
private static Node	getValueParent(GlobalNamespace.Ref ref) Gets the parent node of the value for any assignment to a Name.
private boolean	isAssignAllowed() Determines whether assignment to a define should be allowed at the current point of the traversal.
private boolean	processDefineAssignment(NodeTraversal t, java.lang.String name, Node value, Node valueParent) Tracks the given define.
private static void	setDefineInfoNotAssignable(ProcessDefines.DefineInfo info, NodeTraversal t) Records the fact that because of the current node in the node traversal, the define can't ever be assigned again.
boolean	shouldTraverse(NodeTraversal nodeTraversal, Node n, Node parent) Keeps track of whether the traversal is in a conditional branch.
private void	updateAssignAllowedStack(Node n, boolean entering) Determines whether assignment to a define should be allowed in the subtree of the given node, and if not, records that fact.
void	visit(NodeTraversal t, Node n, Node parent) Visits a node in postorder (after its children have been visited).

Methods inherited from class java.lang.Object

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

Field Detail

compiler

private final AbstractCompiler compiler

assignableDefines

private final java.util.Map<java.lang.String,ProcessDefines.DefineInfo> assignableDefines

allDefines

private final java.util.Map<java.lang.String,ProcessDefines.DefineInfo> allDefines

allRefInfo

private final java.util.Map<Node,ProcessDefines.CollectDefines.RefInfo> allRefInfo

lvalueToRemoveLater

private Node lvalueToRemoveLater

assignAllowed

private final java.util.Deque<java.lang.Integer> assignAllowed

Constructor Detail

CollectDefines

CollectDefines(AbstractCompiler compiler,
               java.util.List<GlobalNamespace.Name> listOfDefines)

Method Detail

getAllDefines

java.util.Map<java.lang.String,ProcessDefines.DefineInfo> getAllDefines()

Get a map of ProcessDefines.DefineInfo structures, keyed by the name of the define.

shouldTraverse

public boolean shouldTraverse(NodeTraversal nodeTraversal,
                              Node n,
                              Node parent)

Keeps track of whether the traversal is in a conditional branch. We traverse all nodes of the parse tree.

Specified by:

shouldTraverse in interface NodeTraversal.Callback

Returns:

whether the children of this node should be visited

visit

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

Description copied from interface: NodeTraversal.Callback

Visits a node in postorder (after its children have been visited). A node is visited only if all its parents should be traversed (NodeTraversal.Callback.shouldTraverse(NodeTraversal, Node, Node)).

Implementations can have side effects (e.g. modifying the parse tree).

Specified by:

visit in interface NodeTraversal.Callback

updateAssignAllowedStack

private void updateAssignAllowedStack(Node n,
                                      boolean entering)

Determines whether assignment to a define should be allowed in the subtree of the given node, and if not, records that fact.

Parameters:

n - The node whose subtree we're about to enter or exit.

entering - True if we're entering the subtree, false otherwise.

isAssignAllowed

private boolean isAssignAllowed()

Determines whether assignment to a define should be allowed at the current point of the traversal.

processDefineAssignment

private boolean processDefineAssignment(NodeTraversal t,
                                        java.lang.String name,
                                        Node value,
                                        Node valueParent)

Tracks the given define.

Parameters:

t - The current traversal, for context.

name - The full name for this define.

value - The value assigned to the define.

valueParent - The parent node of value.

Returns:

Whether we should remove this assignment from the parse tree.

getValueParent

private static Node getValueParent(GlobalNamespace.Ref ref)

Gets the parent node of the value for any assignment to a Name. For example, in the assignment var x = 3; the parent would be the NAME node.

setDefineInfoNotAssignable

private static void setDefineInfoNotAssignable(ProcessDefines.DefineInfo info,
                                               NodeTraversal t)

Records the fact that because of the current node in the node traversal, the define can't ever be assigned again.

Parameters:

info - Represents the define variable.

t - The current traversal.