Add WebKit brace style configuration option.

Summary:
Add brace style `BS_WebKit` as described on https://www.webkit.org/coding/coding-style.html:

* Function definitions: place each brace on its own line.
* Other braces: place the open brace on the line preceding the code block; place the close brace on its own line.

Set brace style used in `getWebKitStyle()` to the newly added `BS_WebKit`.

Reviewers: djasper, klimek

Subscribers: klimek, cfe-commits

Differential Revision: http://reviews.llvm.org/D11837

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@244446 91177308-0d34-0410-b5e6-96231b3b80d8

docs/ClangFormatStyleOptions.rst

@@ -279,13 +279,15 @@ the configuration (without a prefix: ``Auto``).
     Like ``Attach``, but break before braces on enum, function, and record
     definitions.
   * ``BS_Stroustrup`` (in configuration: ``Stroustrup``)
-    Like ``Attach``, but break before function definitions, and 'else'.
+    Like ``Attach``, but break before function definitions, 'catch', and 'else'.
   * ``BS_Allman`` (in configuration: ``Allman``)
     Always break before braces.
   * ``BS_GNU`` (in configuration: ``GNU``)
     Always break before braces and add an extra level of indentation to
     braces of control statements, not to those of class, function
     or other definitions.
+  * ``BS_WebKit`` (in configuration: ``WebKit``)
+    Like ``Attach``, but break before functions.
 
 
 **BreakBeforeTernaryOperators** (``bool``)

include/clang/Format/Format.h

@@ -169,14 +169,16 @@ struct FormatStyle {
     /// Like ``Attach``, but break before braces on enum, function, and record
     /// definitions.
     BS_Mozilla,
-    /// Like \c Attach, but break before function definitions, and 'else'.
+    /// Like \c Attach, but break before function definitions, 'catch', and 'else'.
     BS_Stroustrup,
     /// Always break before braces.
     BS_Allman,
     /// Always break before braces and add an extra level of indentation to
     /// braces of control statements, not to those of class, function
     /// or other definitions.
-    BS_GNU
+    BS_GNU,
+    /// Like ``Attach``, but break before functions.
+    BS_WebKit
   };
 
   /// \brief The brace breaking style to use.

lib/Format/Format.cpp

@@ -98,6 +98,7 @@ template <> struct ScalarEnumerationTraits<FormatStyle::BraceBreakingStyle> {
     IO.enumCase(Value, "Stroustrup", FormatStyle::BS_Stroustrup);
     IO.enumCase(Value, "Allman", FormatStyle::BS_Allman);
     IO.enumCase(Value, "GNU", FormatStyle::BS_GNU);
+    IO.enumCase(Value, "WebKit", FormatStyle::BS_WebKit);
   }
 };
 
@@ -504,7 +505,7 @@ FormatStyle getWebKitStyle() {
   Style.AlignOperands = false;
   Style.AlignTrailingComments = false;
   Style.BreakBeforeBinaryOperators = FormatStyle::BOS_All;
-  Style.BreakBeforeBraces = FormatStyle::BS_Stroustrup;
+  Style.BreakBeforeBraces = FormatStyle::BS_WebKit;
   Style.BreakConstructorInitializersBeforeComma = true;
   Style.Cpp11BracedListStyle = false;
   Style.ColumnLimit = 0;

unittests/Format/FormatTest.cpp

@@ -2329,13 +2329,16 @@ TEST_F(FormatTest, IncompleteTryCatchBlocks) {
 
 TEST_F(FormatTest, FormatTryCatchBraceStyles) {
   FormatStyle Style = getLLVMStyle();
-  Style.BreakBeforeBraces = FormatStyle::BS_Attach;
-  verifyFormat("try {\n"
-               "  // something\n"
-               "} catch (...) {\n"
-               "  // something\n"
-               "}",
-               Style);
+  for (auto BraceStyle :
+       {FormatStyle::BS_Attach, FormatStyle::BS_Mozilla, FormatStyle::BS_WebKit}) {
+    Style.BreakBeforeBraces = BraceStyle;
+    verifyFormat("try {\n"
+                 "  // something\n"
+                 "} catch (...) {\n"
+                 "  // something\n"
+                 "}",
+                 Style);
+  }
   Style.BreakBeforeBraces = FormatStyle::BS_Stroustrup;
   verifyFormat("try {\n"
                "  // something\n"
@@ -9060,6 +9063,45 @@ TEST_F(FormatTest, GNUBraceBreaking) {
                "#endif",
                GNUBraceStyle);
 }
+
+TEST_F(FormatTest, WebKitBraceBreaking) {
+  FormatStyle WebKitBraceStyle = getLLVMStyle();
+  WebKitBraceStyle.BreakBeforeBraces = FormatStyle::BS_WebKit;
+  verifyFormat("namespace a {\n"
+               "class A {\n"
+               "  void f()\n"
+               "  {\n"
+               "    if (true) {\n"
+               "      a();\n"
+               "      b();\n"
+               "    }\n"
+               "  }\n"
+               "  void g() { return; }\n"
+               "};\n"
+               "enum E {\n"
+               "  A,\n"
+               "  // foo\n"
+               "  B,\n"
+               "  C\n"
+               "};\n"
+               "struct B {\n"
+               "  int x;\n"
+               "};\n"
+               "}\n",
+               WebKitBraceStyle);
+  verifyFormat("struct S {\n"
+               "  int Type;\n"
+               "  union {\n"
+               "    int x;\n"
+               "    double y;\n"
+               "  } Value;\n"
+               "  class C {\n"
+               "    MyFavoriteType Value;\n"
+               "  } Class;\n"
+               "};\n",
+               WebKitBraceStyle);
+}
+
 TEST_F(FormatTest, CatchExceptionReferenceBinding) {
   verifyFormat("void f() {\n"
                "  try {\n"
@@ -9336,6 +9378,7 @@ TEST_F(FormatTest, ParsesConfiguration) {
   CHECK_PARSE("BreakBeforeBraces: Allman", BreakBeforeBraces,
               FormatStyle::BS_Allman);
   CHECK_PARSE("BreakBeforeBraces: GNU", BreakBeforeBraces, FormatStyle::BS_GNU);
+  CHECK_PARSE("BreakBeforeBraces: WebKit", BreakBeforeBraces, FormatStyle::BS_WebKit);
 
   Style.AlwaysBreakAfterDefinitionReturnType = FormatStyle::DRTBS_All;
   CHECK_PARSE("AlwaysBreakAfterDefinitionReturnType: None",