com.google.javascript.jscomp

Class TypeCheck

java.lang.Object

com.google.javascript.jscomp.TypeCheck

All Implemented Interfaces:

CompilerPass, NodeTraversal.Callback

public class TypeCheck
extends Object
implements NodeTraversal.Callback, CompilerPass

Checks the types of JS expressions against any declared type information.

Field Summary

Fields

Modifier and Type	Field and Description
protected static DiagnosticType	NOT_A_CONSTRUCTOR
protected static String	OVERRIDING_PROTOTYPE_WITH_NON_OBJECT

Constructor Summary

Constructors

Constructor and Description
TypeCheck(AbstractCompiler compiler, ReverseAbstractInterpreter reverseInterpreter, JSTypeRegistry typeRegistry, CheckLevel reportMissingOverride)
TypeCheck(AbstractCompiler compiler, ReverseAbstractInterpreter reverseInterpreter, JSTypeRegistry typeRegistry, Scope topScope, com.google.javascript.jscomp.MemoizedScopeCreator scopeCreator, CheckLevel reportMissingOverride)

Method Summary

Methods

Modifier and Type	Method and Description
void	check(Node node, boolean externs)
void	process(Node externsRoot, Node jsRoot) Main entry point for this phase of processing.
Scope	processForTesting(Node externsRoot, Node jsRoot) Main entry point of this phase for testing code.
boolean	shouldTraverse(NodeTraversal t, Node n, Node parent) Visits a node in pre order (before visiting its children) and decides whether this node's children should be traversed.
void	visit(NodeTraversal t, Node n, Node parent) This is the meat of the type checking.

Methods inherited from class java.lang.Object

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

Field Detail

OVERRIDING_PROTOTYPE_WITH_NON_OBJECT

protected static final String OVERRIDING_PROTOTYPE_WITH_NON_OBJECT

See Also:

Constant Field Values

NOT_A_CONSTRUCTOR

protected static final DiagnosticType NOT_A_CONSTRUCTOR

Constructor Detail

TypeCheck

public TypeCheck(AbstractCompiler compiler,
         ReverseAbstractInterpreter reverseInterpreter,
         JSTypeRegistry typeRegistry,
         Scope topScope,
         com.google.javascript.jscomp.MemoizedScopeCreator scopeCreator,
         CheckLevel reportMissingOverride)

TypeCheck

public TypeCheck(AbstractCompiler compiler,
         ReverseAbstractInterpreter reverseInterpreter,
         JSTypeRegistry typeRegistry,
         CheckLevel reportMissingOverride)

Method Detail

process

public void process(Node externsRoot,
           Node jsRoot)

Main entry point for this phase of processing. This follows the pattern for JSCompiler phases.

Specified by:

process in interface CompilerPass

Parameters:

externsRoot - The root of the externs parse tree.

jsRoot - The root of the input parse tree to be checked.

processForTesting

public Scope processForTesting(Node externsRoot,
                      Node jsRoot)

Main entry point of this phase for testing code.

check

public void check(Node node,
         boolean externs)

shouldTraverse

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

Description copied from interface: NodeTraversal.Callback

Visits a node in pre order (before visiting its children) and decides whether this node's children should be traversed. If children are traversed, they will be visited by NodeTraversal.Callback.visit(NodeTraversal, Node, Node) in postorder.

Implementations can have side effects (e.g. modifying 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)

This is the meat of the type checking. It is basically one big switch, with each case representing one type of parse tree node. The individual cases are usually pretty straightforward.

Specified by:

visit in interface NodeTraversal.Callback

Parameters:

t - The node traversal object that supplies context, such as the scope chain to use in name lookups as well as error reporting.

n - The node being visited.

parent - The parent of the node n.