From a830c844b7846f56a785d0ed8a2e75d4bec7a14f Mon Sep 17 00:00:00 2001
From: Sheetal Nandi <shkamat@microsoft.com>
Date: Tue, 4 Oct 2016 12:25:07 -0700
Subject: [PATCH] Bind the source file as external module only if not already
 done Return type of require call is from external module resolution only if
 it doesnt resolve to local module Fixes #10931

---
 src/compiler/binder.ts                        |  4 +-
 src/compiler/checker.ts                       |  5 ++-
 ...quireAsFunctionInExternalModule.errors.txt | 20 ----------
 .../requireAsFunctionInExternalModule.symbols | 31 ++++++++++++++++
 .../requireAsFunctionInExternalModule.types   | 37 +++++++++++++++++++
 5 files changed, 75 insertions(+), 22 deletions(-)
 delete mode 100644 tests/baselines/reference/requireAsFunctionInExternalModule.errors.txt
 create mode 100644 tests/baselines/reference/requireAsFunctionInExternalModule.symbols
 create mode 100644 tests/baselines/reference/requireAsFunctionInExternalModule.types

diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
index 2fe7d30ab56..c8785819b9e 100644
--- a/src/compiler/binder.ts
+++ b/src/compiler/binder.ts
@@ -2000,7 +2000,9 @@ namespace ts {
         function setCommonJsModuleIndicator(node: Node) {
             if (!file.commonJsModuleIndicator) {
                 file.commonJsModuleIndicator = node;
-                bindSourceFileAsExternalModule();
+                if (!file.externalModuleIndicator) {
+                    bindSourceFileAsExternalModule();
+                }
             }
         }
 
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 422f2a70dcc..1354002a29e 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -12535,7 +12535,10 @@ namespace ts {
             }
 
             // In JavaScript files, calls to any identifier 'require' are treated as external module imports
-            if (isInJavaScriptFile(node) && isRequireCall(node, /*checkArgumentIsStringLiteral*/true)) {
+            if (isInJavaScriptFile(node) &&
+                isRequireCall(node, /*checkArgumentIsStringLiteral*/true) &&
+                // Make sure require is not a local function
+                !resolveName(node.expression, (<Identifier>node.expression).text, SymbolFlags.Value | SymbolFlags.ExportValue, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined)) {
                 return resolveExternalModuleTypeByLiteral(<StringLiteral>node.arguments[0]);
             }
 
diff --git a/tests/baselines/reference/requireAsFunctionInExternalModule.errors.txt b/tests/baselines/reference/requireAsFunctionInExternalModule.errors.txt
deleted file mode 100644
index 58e3b145f35..00000000000
--- a/tests/baselines/reference/requireAsFunctionInExternalModule.errors.txt
+++ /dev/null
@@ -1,20 +0,0 @@
-tests/cases/compiler/m2.ts(1,10): error TS2305: Module '"tests/cases/compiler/m"' has no exported member 'hello'.
-
-
-==== tests/cases/compiler/c.js (0 errors) ====
-    export default function require(a) { }
-    export function has(a) { return true }
-    
-==== tests/cases/compiler/m.js (0 errors) ====
-    import require, { has } from "./c"
-    export function hello() { }
-    if (has('ember-debug')) {
-        require('ember-debug');
-    }
-    
-==== tests/cases/compiler/m2.ts (1 errors) ====
-    import { hello } from "./m";
-             ~~~~~
-!!! error TS2305: Module '"tests/cases/compiler/m"' has no exported member 'hello'.
-    hello();
-    
\ No newline at end of file
diff --git a/tests/baselines/reference/requireAsFunctionInExternalModule.symbols b/tests/baselines/reference/requireAsFunctionInExternalModule.symbols
new file mode 100644
index 00000000000..2f44d6b6611
--- /dev/null
+++ b/tests/baselines/reference/requireAsFunctionInExternalModule.symbols
@@ -0,0 +1,31 @@
+=== tests/cases/compiler/c.js ===
+export default function require(a) { }
+>require : Symbol(require, Decl(c.js, 0, 0))
+>a : Symbol(a, Decl(c.js, 0, 32))
+
+export function has(a) { return true }
+>has : Symbol(has, Decl(c.js, 0, 38))
+>a : Symbol(a, Decl(c.js, 1, 20))
+
+=== tests/cases/compiler/m.js ===
+import require, { has } from "./c"
+>require : Symbol(require, Decl(m.js, 0, 6))
+>has : Symbol(has, Decl(m.js, 0, 17))
+
+export function hello() { }
+>hello : Symbol(hello, Decl(m.js, 0, 34))
+
+if (has('ember-debug')) {
+>has : Symbol(has, Decl(m.js, 0, 17))
+
+    require('ember-debug');
+>require : Symbol(require, Decl(m.js, 0, 6))
+}
+
+=== tests/cases/compiler/m2.ts ===
+import { hello } from "./m";
+>hello : Symbol(hello, Decl(m2.ts, 0, 8))
+
+hello();
+>hello : Symbol(hello, Decl(m2.ts, 0, 8))
+
diff --git a/tests/baselines/reference/requireAsFunctionInExternalModule.types b/tests/baselines/reference/requireAsFunctionInExternalModule.types
new file mode 100644
index 00000000000..2ce5f3aed38
--- /dev/null
+++ b/tests/baselines/reference/requireAsFunctionInExternalModule.types
@@ -0,0 +1,37 @@
+=== tests/cases/compiler/c.js ===
+export default function require(a) { }
+>require : (a: any) => void
+>a : any
+
+export function has(a) { return true }
+>has : (a: any) => boolean
+>a : any
+>true : true
+
+=== tests/cases/compiler/m.js ===
+import require, { has } from "./c"
+>require : (a: any) => void
+>has : (a: any) => boolean
+
+export function hello() { }
+>hello : () => void
+
+if (has('ember-debug')) {
+>has('ember-debug') : boolean
+>has : (a: any) => boolean
+>'ember-debug' : "ember-debug"
+
+    require('ember-debug');
+>require('ember-debug') : void
+>require : (a: any) => void
+>'ember-debug' : "ember-debug"
+}
+
+=== tests/cases/compiler/m2.ts ===
+import { hello } from "./m";
+>hello : () => void
+
+hello();
+>hello() : void
+>hello : () => void
+