Merge pull request microsoft#2964 from Microsoft/checkerSimplification

Restore checker simplification that was reverted due to a bad merge.

Author: CyrusNajmabadi

src/compiler/checker.ts

@@ -2473,7 +2473,7 @@ module ts {
  let declaration = <ClassDeclaration>getDeclarationOfKind(type.symbol, SyntaxKind.ClassDeclaration);
  let baseTypeNode = getClassExtendsHeritageClauseElement(declaration);
  if (baseTypeNode) {
- let baseType = getTypeFromExpressionWithTypeArguments(baseTypeNode);
+ let baseType = getTypeFromTypeNode(baseTypeNode);
  if (baseType !== unknownType) {
  if (getTargetType(baseType).flags & TypeFlags.Class) {
  if (type !== baseType && !hasBaseType(<InterfaceType>baseType, type)) {
@@ -2495,7 +2495,7 @@ module ts {
  for (let declaration of type.symbol.declarations) {
  if (declaration.kind === SyntaxKind.InterfaceDeclaration && getInterfaceBaseTypeNodes(<InterfaceDeclaration>declaration)) {
  for (let node of getInterfaceBaseTypeNodes(<InterfaceDeclaration>declaration)) {
- let baseType = getTypeFromExpressionWithTypeArguments(node);
+ let baseType = getTypeFromTypeNode(node);
 
  if (baseType !== unknownType) {
  if (getTargetType(baseType).flags & (TypeFlags.Class | TypeFlags.Interface)) {
@@ -3359,14 +3359,6 @@ module ts {
  }
  }
 
- function getTypeFromTypeReference(node: TypeReferenceNode): Type {
- return getTypeFromTypeReferenceOrExpressionWithTypeArguments(node);
- }
-
- function getTypeFromExpressionWithTypeArguments(node: ExpressionWithTypeArguments): Type {
- return getTypeFromTypeReferenceOrExpressionWithTypeArguments(node);
- }
-
  function getTypeFromTypeReferenceOrExpressionWithTypeArguments(node: TypeReferenceNode | ExpressionWithTypeArguments): Type {
  let links = getNodeLinks(node);
  if (!links.resolvedType) {
@@ -3667,9 +3659,9 @@ module ts {
  case SyntaxKind.StringLiteral:
  return getTypeFromStringLiteral(<StringLiteral>node);
  case SyntaxKind.TypeReference:
- return getTypeFromTypeReference(<TypeReferenceNode>node);
+ return getTypeFromTypeReferenceOrExpressionWithTypeArguments(<TypeReferenceNode>node);
  case SyntaxKind.ExpressionWithTypeArguments:
- return getTypeFromExpressionWithTypeArguments(<ExpressionWithTypeArguments>node);
+ return getTypeFromTypeReferenceOrExpressionWithTypeArguments(<ExpressionWithTypeArguments>node);
  case SyntaxKind.TypeQuery:
  return getTypeFromTypeQueryNode(<TypeQueryNode>node);
  case SyntaxKind.ArrayType:
@@ -9997,7 +9989,7 @@ module ts {
 
  checkExpressionWithTypeArguments(typeRefNode);
  if (produceDiagnostics) {
- let t = getTypeFromExpressionWithTypeArguments(typeRefNode);
+ let t = getTypeFromTypeNode(typeRefNode);
  if (t !== unknownType) {
  let declaredType = (t.flags & TypeFlags.Reference) ? (<TypeReference>t).target : t;
  if (declaredType.flags & (TypeFlags.Class | TypeFlags.Interface)) {
@@ -11695,7 +11687,7 @@ module ts {
  // * The serialized type of a TypeReference with a value declaration is its entity name.
  // * The serialized type of a TypeReference with a call or construct signature is "Function".
  // * The serialized type of any other type is "Object".
- let type = getTypeFromTypeReference(node);
+ let type = getTypeFromTypeNode(node);
  if (type.flags & TypeFlags.Void) {
  return "void 0";
  }