From 60bd2624370f057ffe3acb70eb8898569cbd94d2 Mon Sep 17 00:00:00 2001
From: Andy <anhans@microsoft.com>
Date: Mon, 18 Dec 2017 12:41:05 -0800
Subject: [PATCH] Don't treat class name as a completion list blocker if the
 position comes after it (#20762)

---
 src/services/completions.ts                         |  5 ++++-
 tests/cases/fourslash/completionsKeywordsExtends.ts | 11 +++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)
 create mode 100644 tests/cases/fourslash/completionsKeywordsExtends.ts

diff --git a/src/services/completions.ts b/src/services/completions.ts
index 85095f65cef..a7020823d2e 100644
--- a/src/services/completions.ts
+++ b/src/services/completions.ts
@@ -1760,7 +1760,10 @@ namespace ts.Completions {
                     return true;
             }
 
-            return isDeclarationName(contextToken) && !isJsxAttribute(contextToken.parent);
+            return isDeclarationName(contextToken)
+                && !isJsxAttribute(contextToken.parent)
+                // Don't block completions if we're in `class C /**/`, because we're *past* the end of the identifier and might want to complete `extends`.
+                && !(isClassLike(contextToken.parent) && position > previousToken.end);
         }
 
         function isFunctionLikeButNotConstructor(kind: SyntaxKind) {
diff --git a/tests/cases/fourslash/completionsKeywordsExtends.ts b/tests/cases/fourslash/completionsKeywordsExtends.ts
new file mode 100644
index 00000000000..065d30d1286
--- /dev/null
+++ b/tests/cases/fourslash/completionsKeywordsExtends.ts
@@ -0,0 +1,11 @@
+/// <reference path="fourslash.ts" />
+
+////class C/*a*/ /*b*/ { }
+
+// Tests that `isCompletionListBlocker` is true *at* the class name, but false *after* it.
+
+goTo.marker("a");
+verify.completionListIsEmpty();
+
+goTo.marker("b");
+verify.completionListContains("extends");