clang-format: [JS] Support ES6 spread operator.

Specifically, don't add a space before it.

Before:
  someFunction(... a);
  var x = [1, 2, ... a];

After:
  someFunction(...a);
  var x = [1, 2, ...a];

llvm-svn: 238183

2 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index c2e29080dcf..8229471071c 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -1874,6 +1874,8 @@ bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
     if ((Left.is(tok::l_brace) || Right.is(tok::r_brace)) &&
         Line.First->isOneOf(Keywords.kw_import, tok::kw_export))
       return false;
+    if (Left.is(tok::ellipsis))
+      return false;
     if (Left.is(TT_TemplateCloser) &&
         !Right.isOneOf(tok::equal, tok::l_brace, tok::comma, tok::l_square,
                        Keywords.kw_implements, Keywords.kw_extends))
diff --git a/clang/unittests/Format/FormatTestJS.cpp b/clang/unittests/Format/FormatTestJS.cpp
index 1481ef0f285..d5625a27976 100644
--- a/clang/unittests/Format/FormatTestJS.cpp
+++ b/clang/unittests/Format/FormatTestJS.cpp
@@ -82,6 +82,10 @@ TEST_F(FormatTestJS, UnderstandsJavaScriptOperators) {
 
   verifyFormat("var b = a.map((x) => x + 1);");
   verifyFormat("return ('aaa') in bbbb;");
+
+  // ES6 spread operator.
+  verifyFormat("someFunction(...a);");
+  verifyFormat("var x = [1, ...a, 2];");
 }
 
 TEST_F(FormatTestJS, UnderstandsAmpAmp) {