Make utility mehtod names clearer.

Author: CyrusNajmabadi

src/compiler/types.ts

@@ -325,14 +325,12 @@ module ts {
 
  // Context flags computed by aggregating child flags upwards.
 
- // If this node, or any of it's children (transitively) contain an error. 
+ // Used during incremental parsing to determine if this node or any of its children had an 
+ // error. Computed only once and then cached.
  ThisNodeOrAnySubNodesHasError = 1 << 5,
 
- // Used during incremental parsing to determine if we need to visit this node to see if
- // any of its children had an error. Once we compute that once, we can set this bit on the
- // node to know that we never have to do it again. From that point on, we can just check
- // the node directly for 'ContainsError'.
- HasComputedThisNodeOrAnySubNodesHasError = 1 << 6
+ // Used to know if we've computed data from children and cached it in this node.
+ HasAggregatedChildData = 1 << 6
  }
 
  export interface Node extends TextRange {

src/compiler/utilities.ts

@@ -62,31 +62,34 @@ module ts {
  return node.end - node.pos;
  }
 
- export function hasFlag(val: number, flag: number): boolean {
+ function hasFlag(val: number, flag: number): boolean {
  return (val & flag) !== 0;
  }
 
  // Returns true if this node contains a parse error anywhere underneath it.
  export function containsParseError(node: Node): boolean {
- if (!hasFlag(node.parserContextFlags, ParserContextFlags.HasComputedThisNodeOrAnySubNodesHasError)) {
+ aggregateChildData(node);
+ return hasFlag(node.parserContextFlags, ParserContextFlags.ThisNodeOrAnySubNodesHasError);
+ }
+
+ function aggregateChildData(node: Node): void {
+ if (!hasFlag(node.parserContextFlags, ParserContextFlags.HasAggregatedChildData)) {
  // A node is considered to contain a parse error if:
  // a) the parser explicitly marked that it had an error
  // b) any of it's children reported that it had an error.
- var val = hasFlag(node.parserContextFlags, ParserContextFlags.ThisNodeHasError) ||
+ var thisNodeOrAnySubNodesHasError = hasFlag(node.parserContextFlags, ParserContextFlags.ThisNodeHasError) ||
  forEachChild(node, containsParseError);
 
  // If so, mark ourselves accordingly. 
- if (val) {
+ if (thisNodeOrAnySubNodesHasError) {
  node.parserContextFlags |= ParserContextFlags.ThisNodeOrAnySubNodesHasError;
  }
 
  // Also mark that we've propogated the child information to this node. This way we can
  // always consult the bit directly on this node without needing to check its children
  // again.
- node.parserContextFlags |= ParserContextFlags.HasComputedThisNodeOrAnySubNodesHasError;
+ node.parserContextFlags |= ParserContextFlags.HasAggregatedChildData;
  }
-
- return hasFlag(node.parserContextFlags, ParserContextFlags.ThisNodeOrAnySubNodesHasError);
  }
 
  export function getSourceFileOfNode(node: Node): SourceFile {