From 4dc827e22ade0a39db5c32beba2e0f22e09e2fe9 Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Tue, 31 Mar 2020 14:59:47 -0700
Subject: [PATCH] Fix emit of simple module.exports.C.prototype pattern
 (#37719)

Extends the fix of #36108 so that the simple example gets correct emit;
the complex test case I came up with still doesn't work correctly, but
the actual code froma #35228 is fixed.
---
 src/compiler/checker.ts                                       | 2 +-
 .../jsDeclarationsExportAssignedConstructorFunction.js        | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index eec6b03dddc..3ba610453c0 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -5648,7 +5648,7 @@ namespace ts {
                         serializeEnum(symbol, symbolName, modifierFlags);
                     }
                     if (symbol.flags & SymbolFlags.Class) {
-                        if (symbol.flags & SymbolFlags.Property) {
+                        if (symbol.flags & SymbolFlags.Property && isBinaryExpression(symbol.valueDeclaration.parent) && isClassExpression(symbol.valueDeclaration.parent.right)) {
                             // Looks like a `module.exports.Sub = class {}` - if we serialize `symbol` as a class, the result will have no members,
                             // since the classiness is actually from the target of the effective alias the symbol is. yes. A BlockScopedVariable|Class|Property
                             // _really_ acts like an Alias, and none of a BlockScopedVariable, Class, or Property. This is the travesty of JS binding today.
diff --git a/tests/baselines/reference/jsDeclarationsExportAssignedConstructorFunction.js b/tests/baselines/reference/jsDeclarationsExportAssignedConstructorFunction.js
index aa2f0d2a0a9..747a2627d42 100644
--- a/tests/baselines/reference/jsDeclarationsExportAssignedConstructorFunction.js
+++ b/tests/baselines/reference/jsDeclarationsExportAssignedConstructorFunction.js
@@ -21,4 +21,6 @@ module.exports.MyClass.prototype = {
 
 
 //// [jsDeclarationsExportAssignedConstructorFunction.d.ts]
-export {};
+export class MyClass {
+    a: () => void;
+}