pr feedback

Author: jbedard

src/ng/parse.js

@@ -623,7 +623,7 @@ function isStateless($filter, filterName) {
 }
 
 // Detect nodes which could depend on non-shallow state of objects
-function isPure(node, parentPureness) {
+function isPure(node, parentIsPure) {
   switch (node.type) {
     // Computed members might invoke a stateful toString()
     case AST.MemberExpression:
@@ -632,6 +632,7 @@ function isPure(node, parentPureness) {
       }
       break;
 
+    // Unary always convert to primative
     case AST.UnaryExpression:
       return true;
 
@@ -644,15 +645,15 @@ function isPure(node, parentPureness) {
       return false;
   }
 
-  return parentPureness;
+  return (undefined === parentIsPure) || parentIsPure;
 }
 
 function findConstantAndWatchExpressions(ast, $filter, parentIsPure) {
   var allConstants;
   var argsToWatch;
   var isStatelessFilter;
 
-  ast.isPure = parentIsPure = isPure(ast, (undefined === parentIsPure) || parentIsPure);
+  ast.isPure = parentIsPure = isPure(ast, parentIsPure);
 
   switch (ast.type) {
   case AST.Program: