clang-format: [JS] do not clean up duplicated commas.

Summary:
In JavaScript, duplicated commas have semantic meaning.
    x = [a,,b];

The statement above creates an array with three entries, the middle being undefined. Because clang-format should not change semantics, disable this cleanup in JS.

Reviewers: djasper

Subscribers: klimek

Differential Revision: https://reviews.llvm.org/D33641

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@304141 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 2 deletions

diff --git a/unittests/Format/CleanupTest.cpp b/unittests/Format/CleanupTest.cpp
index e554a81912..708fdf8968 100644
--- a/unittests/Format/CleanupTest.cpp
+++ b/unittests/Format/CleanupTest.cpp
@@ -36,11 +36,12 @@ protected:
 
   // Returns code after cleanup around \p Offsets.
   std::string cleanupAroundOffsets(llvm::ArrayRef<unsigned> Offsets,
-                                   llvm::StringRef Code) {
+                                   llvm::StringRef Code,
+                                   const FormatStyle &Style = getLLVMStyle()) {
     std::vector<tooling::Range> Ranges;
     for (auto Offset : Offsets)
       Ranges.push_back(tooling::Range(Offset, 0));
-    return cleanup(Code, Ranges);
+    return cleanup(Code, Ranges, Style);
   }
 };
 
@@ -171,6 +172,14 @@ TEST_F(CleanupTest, ListRedundantComma) {
   EXPECT_EQ(Expected, cleanupAroundOffsets({17, 22}, Code));
 }
 
+TEST_F(CleanupTest, NoCleanupsForJavaScript) {
+  std::string Code = "function f() { var x = [a, b, , c]; }";
+  std::string Expected = "function f() { var x = [a, b, , c]; }";
+  const FormatStyle &Style = getGoogleStyle(FormatStyle::LK_JavaScript);
+
+  EXPECT_EQ(Expected, cleanupAroundOffsets({30}, Code, Style));
+}
+
 TEST_F(CleanupTest, TrailingCommaInParens) {
   std::string Code = "int main() { f(,1,,2,3,f(1,2,),4,,);}";
   std::string Expected = "int main() { f(1,2,3,f(1,2),4);}";