From 74dd1c05586979f5066f565ab5ae52f8bd47f757 Mon Sep 17 00:00:00 2001
From: Mohamed Hegazy <mhegazy@microsoft.com>
Date: Tue, 28 Mar 2017 10:19:09 -0700
Subject: [PATCH] Handel empty intializer in system module emit

---
 src/compiler/transformers/module/system.ts    |  4 ++
 .../SystemModuleForStatementNoInitializer.js  | 42 +++++++++++++++++++
 ...temModuleForStatementNoInitializer.symbols | 28 +++++++++++++
 ...ystemModuleForStatementNoInitializer.types | 33 +++++++++++++++
 .../SystemModuleForStatementNoInitializer.ts  | 18 ++++++++
 5 files changed, 125 insertions(+)
 create mode 100644 tests/baselines/reference/SystemModuleForStatementNoInitializer.js
 create mode 100644 tests/baselines/reference/SystemModuleForStatementNoInitializer.symbols
 create mode 100644 tests/baselines/reference/SystemModuleForStatementNoInitializer.types
 create mode 100644 tests/cases/compiler/SystemModuleForStatementNoInitializer.ts

diff --git a/src/compiler/transformers/module/system.ts b/src/compiler/transformers/module/system.ts
index 642ac1ce6f..3daeee1e6d 100644
--- a/src/compiler/transformers/module/system.ts
+++ b/src/compiler/transformers/module/system.ts
@@ -1287,6 +1287,10 @@ namespace ts {
          * @param node The node to visit.
          */
         function visitForInitializer(node: ForInitializer): ForInitializer {
+            if (!node) {
+                return node;
+            }
+
             if (shouldHoistForInitializer(node)) {
                 let expressions: Expression[];
                 for (const variable of node.declarations) {
diff --git a/tests/baselines/reference/SystemModuleForStatementNoInitializer.js b/tests/baselines/reference/SystemModuleForStatementNoInitializer.js
new file mode 100644
index 0000000000..6da7fe2e31
--- /dev/null
+++ b/tests/baselines/reference/SystemModuleForStatementNoInitializer.js
@@ -0,0 +1,42 @@
+//// [SystemModuleForStatementNoInitializer.ts]
+
+export { };
+
+let i = 0;
+let limit = 10;
+
+for (; i < limit; ++i) {
+    break;
+}
+
+for (; ; ++i) {
+    break;
+}
+
+for (; ;) {
+    break;
+}
+
+
+//// [SystemModuleForStatementNoInitializer.js]
+System.register([], function (exports_1, context_1) {
+    "use strict";
+    var __moduleName = context_1 && context_1.id;
+    var i, limit;
+    return {
+        setters: [],
+        execute: function () {
+            i = 0;
+            limit = 10;
+            for (; i < limit; ++i) {
+                break;
+            }
+            for (;; ++i) {
+                break;
+            }
+            for (;;) {
+                break;
+            }
+        }
+    };
+});
diff --git a/tests/baselines/reference/SystemModuleForStatementNoInitializer.symbols b/tests/baselines/reference/SystemModuleForStatementNoInitializer.symbols
new file mode 100644
index 0000000000..e8a7609120
--- /dev/null
+++ b/tests/baselines/reference/SystemModuleForStatementNoInitializer.symbols
@@ -0,0 +1,28 @@
+=== tests/cases/compiler/SystemModuleForStatementNoInitializer.ts ===
+
+export { };
+
+let i = 0;
+>i : Symbol(i, Decl(SystemModuleForStatementNoInitializer.ts, 3, 3))
+
+let limit = 10;
+>limit : Symbol(limit, Decl(SystemModuleForStatementNoInitializer.ts, 4, 3))
+
+for (; i < limit; ++i) {
+>i : Symbol(i, Decl(SystemModuleForStatementNoInitializer.ts, 3, 3))
+>limit : Symbol(limit, Decl(SystemModuleForStatementNoInitializer.ts, 4, 3))
+>i : Symbol(i, Decl(SystemModuleForStatementNoInitializer.ts, 3, 3))
+
+    break;
+}
+
+for (; ; ++i) {
+>i : Symbol(i, Decl(SystemModuleForStatementNoInitializer.ts, 3, 3))
+
+    break;
+}
+
+for (; ;) {
+    break;
+}
+
diff --git a/tests/baselines/reference/SystemModuleForStatementNoInitializer.types b/tests/baselines/reference/SystemModuleForStatementNoInitializer.types
new file mode 100644
index 0000000000..b7b46cb589
--- /dev/null
+++ b/tests/baselines/reference/SystemModuleForStatementNoInitializer.types
@@ -0,0 +1,33 @@
+=== tests/cases/compiler/SystemModuleForStatementNoInitializer.ts ===
+
+export { };
+
+let i = 0;
+>i : number
+>0 : 0
+
+let limit = 10;
+>limit : number
+>10 : 10
+
+for (; i < limit; ++i) {
+>i < limit : boolean
+>i : number
+>limit : number
+>++i : number
+>i : number
+
+    break;
+}
+
+for (; ; ++i) {
+>++i : number
+>i : number
+
+    break;
+}
+
+for (; ;) {
+    break;
+}
+
diff --git a/tests/cases/compiler/SystemModuleForStatementNoInitializer.ts b/tests/cases/compiler/SystemModuleForStatementNoInitializer.ts
new file mode 100644
index 0000000000..15a0d5ac9e
--- /dev/null
+++ b/tests/cases/compiler/SystemModuleForStatementNoInitializer.ts
@@ -0,0 +1,18 @@
+//@module: system
+
+export { };
+
+let i = 0;
+let limit = 10;
+
+for (; i < limit; ++i) {
+    break;
+}
+
+for (; ; ++i) {
+    break;
+}
+
+for (; ;) {
+    break;
+}