Index: lib/Format/UnwrappedLineParser.cpp
===================================================================
--- lib/Format/UnwrappedLineParser.cpp
+++ lib/Format/UnwrappedLineParser.cpp
@@ -1541,7 +1541,8 @@
     // it is often token-pasted.
     while (FormatTok->is(tok::identifier) || FormatTok->is(tok::coloncolon) ||
            FormatTok->is(tok::hashhash) ||
-           (Style.Language == FormatStyle::LK_Java &&
+           ((Style.Language == FormatStyle::LK_Java ||
+             Style.Language == FormatStyle::LK_JavaScript) &&
             FormatTok->isOneOf(tok::period, tok::comma)))
       nextToken();
 
Index: unittests/Format/FormatTestJS.cpp
===================================================================
--- unittests/Format/FormatTestJS.cpp
+++ unittests/Format/FormatTestJS.cpp
@@ -544,6 +544,7 @@
   verifyFormat("class C {\n  private static x: string = 12;\n}");
   verifyFormat("class C {\n  static x(): string { return 'asd'; }\n}");
   verifyFormat("class C extends P implements I {}");
+  verifyFormat("class C extends p.P implements i.I {}");
 }
 
 TEST_F(FormatTestJS, MetadataAnnotations) {