From cbde25f2298d4d3f5c47ea62877bc9017dedddaf Mon Sep 17 00:00:00 2001
From: Sheetal Nandi <shkamat@microsoft.com>
Date: Fri, 18 Nov 2016 11:01:28 -0800
Subject: [PATCH] Handle the scenario when heritage clause of interface is not
 entity name expression Fixes #12291

---
 src/compiler/declarationEmitter.ts             |  5 ++++-
 ...hNonEntityNameExpressionHeritage.errors.txt |  9 +++++++++
 ...rfaceWithNonEntityNameExpressionHeritage.js | 18 ++++++++++++++++++
 ...rfaceWithNonEntityNameExpressionHeritage.ts |  4 ++++
 4 files changed, 35 insertions(+), 1 deletion(-)
 create mode 100644 tests/baselines/reference/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.errors.txt
 create mode 100644 tests/baselines/reference/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.js
 create mode 100644 tests/cases/compiler/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.ts

diff --git a/src/compiler/declarationEmitter.ts b/src/compiler/declarationEmitter.ts
index 7d2f61b6d6f..a7f24dc6321 100644
--- a/src/compiler/declarationEmitter.ts
+++ b/src/compiler/declarationEmitter.ts
@@ -1143,7 +1143,10 @@ namespace ts {
             const prevEnclosingDeclaration = enclosingDeclaration;
             enclosingDeclaration = node;
             emitTypeParameters(node.typeParameters);
-            emitHeritageClause(getInterfaceBaseTypeNodes(node), /*isImplementsList*/ false);
+            const interfaceExtendsTypes = filter(getInterfaceBaseTypeNodes(node), base => isEntityNameExpression(base.expression));
+            if (interfaceExtendsTypes && interfaceExtendsTypes.length) {
+                emitHeritageClause(interfaceExtendsTypes, /*isImplementsList*/ false);
+            }
             write(" {");
             writeLine();
             increaseIndent();
diff --git a/tests/baselines/reference/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.errors.txt b/tests/baselines/reference/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.errors.txt
new file mode 100644
index 00000000000..7dc3a70fdc7
--- /dev/null
+++ b/tests/baselines/reference/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.errors.txt
@@ -0,0 +1,9 @@
+tests/cases/compiler/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.ts(3,25): error TS2499: An interface can only extend an identifier/qualified-name with optional type arguments.
+
+
+==== tests/cases/compiler/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.ts (1 errors) ====
+    
+    class A { }
+    interface Class extends (typeof A) { }
+                            ~~~~~~~~~~
+!!! error TS2499: An interface can only extend an identifier/qualified-name with optional type arguments.
\ No newline at end of file
diff --git a/tests/baselines/reference/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.js b/tests/baselines/reference/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.js
new file mode 100644
index 00000000000..ef2d2e479b0
--- /dev/null
+++ b/tests/baselines/reference/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.js
@@ -0,0 +1,18 @@
+//// [declarationEmitInterfaceWithNonEntityNameExpressionHeritage.ts]
+
+class A { }
+interface Class extends (typeof A) { }
+
+//// [declarationEmitInterfaceWithNonEntityNameExpressionHeritage.js]
+var A = (function () {
+    function A() {
+    }
+    return A;
+}());
+
+
+//// [declarationEmitInterfaceWithNonEntityNameExpressionHeritage.d.ts]
+declare class A {
+}
+interface Class {
+}
diff --git a/tests/cases/compiler/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.ts b/tests/cases/compiler/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.ts
new file mode 100644
index 00000000000..762adaad657
--- /dev/null
+++ b/tests/cases/compiler/declarationEmitInterfaceWithNonEntityNameExpressionHeritage.ts
@@ -0,0 +1,4 @@
+// @declaration: true
+
+class A { }
+interface Class extends (typeof A) { }
\ No newline at end of file