[clang-format] [PR43100] clang-format C# support does not add a space between "using" and paren

Summary:
Addresses https://bugs.llvm.org/show_bug.cgi?id=43100

Formatting using statement in C# with clang-format removes the space between using and paren even when SpaceBeforeParens is !

```
using(FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read, bufferSize : 1))
```

this change simply overcomes this for when using C# settings in the .clang-format file

```
using (FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read, bufferSize : 1))
```

All FormatTests pass..

```
[==========] 688 tests from 21 test cases ran. (88508 ms total)
[  PASSED  ] 688 tests.
```

Reviewers: djasper, klimek, owenpan

Reviewed By: owenpan

Subscribers: llvm-commits, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66662

llvm-svn: 371720

1 files changed, 15 insertions, 0 deletions

diff --git a/clang/unittests/Format/FormatTestCSharp.cpp b/clang/unittests/Format/FormatTestCSharp.cpp
index 801adb28bd9..7fda9566dc8 100644
--- a/clang/unittests/Format/FormatTestCSharp.cpp
+++ b/clang/unittests/Format/FormatTestCSharp.cpp
@@ -165,6 +165,21 @@ TEST_F(FormatTestCSharp, Attributes) {
                "public string Host {\n  set;\n  get;\n}");
 }
 
+TEST_F(FormatTestCSharp, CSharpUsing) {
+  FormatStyle Style = getGoogleStyle(FormatStyle::LK_CSharp);
+  Style.SpaceBeforeParens = FormatStyle::SBPO_Always;
+  verifyFormat("public void foo() {\n"
+               "  using (StreamWriter sw = new StreamWriter (filenameA)) {}\n"
+               "}",
+               Style);
+
+  Style.SpaceBeforeParens = FormatStyle::SBPO_Never;
+  verifyFormat("public void foo() {\n"
+               "  using(StreamWriter sw = new StreamWriter(filenameB)) {}\n"
+               "}",
+               Style);
+}
+
 TEST_F(FormatTestCSharp, CSharpRegions) {
   verifyFormat("#region aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaaaaaaaaaaaaaa "
                "aaaaaaaaaaaaaaa long region");