From a4cf79baa5fddedff71f1ad7bd96b783e67c9009 Mon Sep 17 00:00:00 2001
From: Andy <anhans@microsoft.com>
Date: Mon, 25 Sep 2017 09:47:53 -0700
Subject: [PATCH] Span length is not optional (#18558)

* Span length is not optional

* Fix calculation of length
---
 src/services/refactorProvider.ts        | 4 ++++
 src/services/refactors/extractMethod.ts | 7 +++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/services/refactorProvider.ts b/src/services/refactorProvider.ts
index 432df8c53d0..c8dc1cf360a 100644
--- a/src/services/refactorProvider.ts
+++ b/src/services/refactorProvider.ts
@@ -43,4 +43,8 @@ namespace ts {
             return refactor && refactor.getEditsForAction(context, actionName);
         }
     }
+
+    export function getRefactorContextLength(context: RefactorContext): number {
+        return context.endPosition === undefined ? 0 : context.endPosition - context.startPosition;
+    }
 }
diff --git a/src/services/refactors/extractMethod.ts b/src/services/refactors/extractMethod.ts
index c440c83ebd2..481834c5a09 100644
--- a/src/services/refactors/extractMethod.ts
+++ b/src/services/refactors/extractMethod.ts
@@ -14,7 +14,7 @@ namespace ts.refactor.extractMethod {
 
     /** Compute the associated code actions */
     function getAvailableActions(context: RefactorContext): ApplicableRefactorInfo[] | undefined {
-        const rangeToExtract = getRangeToExtract(context.file, { start: context.startPosition, length: context.endPosition - context.startPosition });
+        const rangeToExtract = getRangeToExtract(context.file, { start: context.startPosition, length: getRefactorContextLength(context) });
 
         const targetRange: TargetRange = rangeToExtract.targetRange;
         if (targetRange === undefined) {
@@ -66,8 +66,7 @@ namespace ts.refactor.extractMethod {
     }
 
     function getEditsForAction(context: RefactorContext, actionName: string): RefactorEditInfo | undefined {
-        const length = context.endPosition === undefined ? 0 : context.endPosition - context.startPosition;
-        const rangeToExtract = getRangeToExtract(context.file, { start: context.startPosition, length });
+        const rangeToExtract = getRangeToExtract(context.file, { start: context.startPosition, length: getRefactorContextLength(context) });
         const targetRange: TargetRange = rangeToExtract.targetRange;
 
         const parsedIndexMatch = /^scope_(\d+)$/.exec(actionName);
@@ -148,7 +147,7 @@ namespace ts.refactor.extractMethod {
      */
     // exported only for tests
     export function getRangeToExtract(sourceFile: SourceFile, span: TextSpan): RangeToExtract {
-        const length = span.length || 0;
+        const { length } = span;
 
         if (length === 0) {
             return { errors: [createFileDiagnostic(sourceFile, span.start, length, Messages.StatementOrExpressionExpected)] };