From f13c92f0366acb29c01917bd1ddc18bedf428fda Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Fri, 8 Apr 2016 15:08:22 -0700
Subject: [PATCH] Handle shorthand property assignments

---
 src/compiler/checker.ts   | 13 +++++++++++--
 src/compiler/utilities.ts |  2 +-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 2393b236648..918acb410aa 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -7358,7 +7358,7 @@ namespace ts {
             return createArrayType(elementType);
         }
 
-        function getAssignedTypeOfPropertyAssignment(node: PropertyAssignment): Type {
+        function getAssignedTypeOfPropertyAssignment(node: PropertyAssignment | ShorthandPropertyAssignment): Type {
             const objectType = getAssignedType(<ObjectLiteralExpression>node.parent);
             const text = getTextOfPropertyName(node.name);
             return getTypeOfPropertyOfType(objectType, text) ||
@@ -7367,6 +7367,15 @@ namespace ts {
                 unknownType;
         }
 
+        function getAssignedTypeOfShorthandPropertyAssignment(node: ShorthandPropertyAssignment): Type {
+            if (node.objectAssignmentInitializer) {
+                const defaultType = checkExpressionCached(node.objectAssignmentInitializer);
+                const assignedType = getAssignedTypeOfPropertyAssignment(node);
+                return getUnionType([getTypeWithFacts(assignedType, TypeFacts.NEUndefined), defaultType]);
+            }
+            return getAssignedTypeOfPropertyAssignment(node);
+        }
+
         function getAssignedType(node: Expression): Type {
             const parent = node.parent;
             switch (parent.kind) {
@@ -7383,7 +7392,7 @@ namespace ts {
                 case SyntaxKind.PropertyAssignment:
                     return getAssignedTypeOfPropertyAssignment(<PropertyAssignment>parent);
                 case SyntaxKind.ShorthandPropertyAssignment:
-                    break; // !!! TODO
+                    return getAssignedTypeOfShorthandPropertyAssignment(<ShorthandPropertyAssignment>parent);
             }
             return unknownType;
         }
diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
index 45567538dcd..f6a4b81e6d2 100644
--- a/src/compiler/utilities.ts
+++ b/src/compiler/utilities.ts
@@ -1329,7 +1329,7 @@ namespace ts {
                 node = parent;
                 continue;
             }
-            if (parent.kind === SyntaxKind.PropertyAssignment) {
+            if (parent.kind === SyntaxKind.PropertyAssignment || parent.kind === SyntaxKind.ShorthandPropertyAssignment) {
                 node = parent.parent;
                 continue;
             }