From b7b43fe601babb77e55d5b6b0d94231e39ed0f12 Mon Sep 17 00:00:00 2001
From: Ryan Cavanaugh <RyanCavanaugh@users.noreply.github.com>
Date: Thu, 7 Dec 2017 12:16:29 -0800
Subject: [PATCH] Fixes #20527

---
 src/services/codefixes/inferFromUsage.ts                | 4 ++++
 tests/cases/fourslash/incompleteFunctionCallCodefix3.ts | 7 +++++++
 2 files changed, 11 insertions(+)
 create mode 100644 tests/cases/fourslash/incompleteFunctionCallCodefix3.ts

diff --git a/src/services/codefixes/inferFromUsage.ts b/src/services/codefixes/inferFromUsage.ts
index 25236318612..992770dbd01 100644
--- a/src/services/codefixes/inferFromUsage.ts
+++ b/src/services/codefixes/inferFromUsage.ts
@@ -71,6 +71,10 @@ namespace ts.codefix {
         }
 
         const containingFunction = getContainingFunction(token);
+        if (containingFunction === undefined) {
+            // Possible in certain syntax error cases
+            return undefined;
+        }
         switch (errorCode) {
             // Variable and Property declarations
             case Diagnostics.Member_0_implicitly_has_an_1_type.code:
diff --git a/tests/cases/fourslash/incompleteFunctionCallCodefix3.ts b/tests/cases/fourslash/incompleteFunctionCallCodefix3.ts
new file mode 100644
index 00000000000..3c0261e48a7
--- /dev/null
+++ b/tests/cases/fourslash/incompleteFunctionCallCodefix3.ts
@@ -0,0 +1,7 @@
+/// <reference path='fourslash.ts' />
+
+// @noImplicitAny: true
+//// function ...q) {}} f(10);
+
+verify.not.codeFixAvailable([]);
+