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

[MyDeveloperDay]

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.

[owenpan]

clang/lib/Format/TokenAnnotator.cpp

2618 ↗

(On Diff #216870)

if (Style.isCSharp() && Left.is(tok::kw_using)) would suffice as Right.is(tok::l_paren) is already checked on Line 2613.

clang/unittests/Format/FormatTestCSharp.cpp

169 ↗

(On Diff #216870)

Maybe set SpaceBeforeParens to Always first in order to really test the new behavior?

[owenpan]

clang/unittests/Format/FormatTestCSharp.cpp

169 ↗

(On Diff #216870)

I meant setting SpaceBeforeParens to Always Never.

[owenpan]

clang/unittests/Format/FormatTestCSharp.cpp

169 ↗

(On Diff #216870)

Also, the right parenthesis for the using statement is missing.

[owenpan]

The test case fails after the missing ) is added, so it seems that the patch has no effect.

[owenpan]

The patch would have no effect if the using statement is not in a block, but that would probably be against C# syntax.

Please see my comments about the test cases. Otherwise, LGTM.

clang/unittests/Format/FormatTestCSharp.cpp

168 ↗

(On Diff #217167)

I'd add the following as the first test case because it tests the new behavior. The other two test cases only verify that the patch does not cause regressions. (The SBPO_Always case may be redundant if it's already covered in FormatTest.cpp.)

// SpaceBeforeParens: ControlStatements
verifyFormat("public void foo() {\n"
             "  using (StreamWriter sw = new StreamWriter(filenameA)) {}\n"
             "}");

cfe/trunk/lib/Format/TokenAnnotator.cpp

if ((Left.is(tok::l_brace) && Left.BlockKind != BK_Block) ||
       (Right.is(tok::r_brace) && Right.MatchingParen &&
        Right.MatchingParen->BlockKind != BK_Block))
     return !Style.Cpp11BracedListStyle;
   if (Left.is(TT_BlockComment))
     // No whitespace in x(/*foo=*/1), except for JavaScript.
     return Style.Language == FormatStyle::LK_JavaScript ||
            !Left.TokenText.endswith("=*/");
   if (Right.is(tok::l_paren)) {
+    // using (FileStream fs...
+    if (Style.isCSharp() && Left.is(tok::kw_using) &&
+        Style.SpaceBeforeParens != FormatStyle::SBPO_Never)
+      return true;
     if ((Left.is(tok::r_paren) && Left.is(TT_AttributeParen)) ||
         (Left.is(tok::r_square) && Left.is(TT_AttributeSquare)))
       return true;
     return Line.Type == LT_ObjCDecl || Left.is(tok::semi) ||
            (Style.SpaceBeforeParens != FormatStyle::SBPO_Never &&
             (Left.isOneOf(tok::pp_elif, tok::kw_for, tok::kw_while,
                           tok::kw_switch, tok::kw_case, TT_ForEachMacro,
                           TT_ObjCForIn) ||

cfe/trunk/unittests/Format/FormatTestCSharp.cpp

TEST_F(FormatTestCSharp, Attributes) {
   verifyFormat("[TestMethod]\n"
                "public string Host {\n  set;\n  get;\n}");
 
   verifyFormat("[TestMethod(\"start\", HelpText = \"Starts the server "
                "listening on provided host\")]\n"
                "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");
 }
 
 TEST_F(FormatTestCSharp, CSharpKeyWordEscaping) {
   verifyFormat("public enum var { none, @string, bool, @enum }");
 }