From 6e512a495f235fed8d1a0a10b619e181c2ef2a5c Mon Sep 17 00:00:00 2001
From: Andy <anhans@microsoft.com>
Date: Thu, 14 Sep 2017 11:16:21 -0700
Subject: [PATCH] extractMethod: Don't try to extract an ExpressionStatement
 consisting of a single token (#18450)

* extractMethod: Don't try to extract an ExpressionStatement consisting of a single token

* Move to unit test
---
 src/harness/unittests/extractMethods.ts | 2 ++
 src/services/refactors/extractMethod.ts | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/harness/unittests/extractMethods.ts b/src/harness/unittests/extractMethods.ts
index 5cab0289d67..ca77af61c75 100644
--- a/src/harness/unittests/extractMethods.ts
+++ b/src/harness/unittests/extractMethods.ts
@@ -410,6 +410,8 @@ function test(x: number) {
             "Statement or expression expected."
         ]);
 
+        testExtractRangeFailed("extract-method-not-for-token-expression-statement", `[#|a|]`, ["Select more than a single token."]);
+
         testExtractMethod("extractMethod1",
             `namespace A {
     let x = 1;
diff --git a/src/services/refactors/extractMethod.ts b/src/services/refactors/extractMethod.ts
index 4c24d22a2f3..9ea3d9d11bd 100644
--- a/src/services/refactors/extractMethod.ts
+++ b/src/services/refactors/extractMethod.ts
@@ -231,7 +231,7 @@ namespace ts.refactor.extractMethod {
         }
 
         function checkRootNode(node: Node): Diagnostic[] | undefined {
-            if (isToken(node)) {
+            if (isToken(isExpressionStatement(node) ? node.expression : node)) {
                 return [createDiagnosticForNode(node, Messages.InsufficientSelection)];
             }
             return undefined;