From 758cdf337872067758ab65efbb850cfd6465da1d Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Sun, 30 Aug 2015 15:07:04 -0700
Subject: [PATCH 1/2] Only obtain regular type of fresh object literal type if
 necessary

---
 src/compiler/checker.ts | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index e624eb41d86..58b7e920bff 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -4640,7 +4640,9 @@ namespace ts {
                     // and intersection types are further deconstructed on the target side, we don't want to
                     // make the check again (as it might fail for a partial target type). Therefore we obtain
                     // the regular source type and proceed with that.
-                    source = getRegularTypeOfObjectLiteral(source);
+                    if (target.flags & TypeFlags.UnionOrIntersection) {
+                        source = getRegularTypeOfObjectLiteral(source);
+                    }
                 }
 
                 let saveErrorInfo = errorInfo;

From c05650aea3c473f41f4de0687080620758310527 Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Wed, 9 Sep 2015 16:38:04 -0700
Subject: [PATCH 2/2] Actually cache regular version of fresh object literal
 type

---
 src/compiler/checker.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 58b7e920bff..3d1250616ef 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -5507,6 +5507,7 @@ namespace ts {
                     regularType.constructSignatures = (<ResolvedType>type).constructSignatures;
                     regularType.stringIndexType = (<ResolvedType>type).stringIndexType;
                     regularType.numberIndexType = (<ResolvedType>type).numberIndexType;
+                    (<FreshObjectLiteralType>type).regularType = regularType;
                 }
                 return regularType;
             }