[clang-format]: Add option to insert space after locical not operator

[reuk]

Summary

This patch aims to support the following rule from the Juce coding standards:

The ! operator should always be followed by a space, e.g. if (! foo)

Leaving a space after ! stops it from blending into the rest of the expression, which makes it easier to tell at a glance what the expression is doing.

Patch by Reuben Thomas

[MyDeveloperDay]

just a few nits, apart form that it LG

clang/include/clang/Format/Format.h

1728

nit: end the sentence with a "."

1929

nit: so I recently observed that these are alphabetic, move this up to line 1916

clang/lib/Format/Format.cpp

493

nit: these are alphabetic

clang/unittests/Format/FormatTest.cpp

9730

could you add an example where someone does !! would it appear as ! ! ( or '!!'

[MyDeveloperDay]

I actually also tend to change doc/ClangFormatStyleOptions.rst too

[reuk]

Updated with fixes. Thanks for pointing out that the options are ordered alphabetically, I hadn't noticed that!

[reuk]

I updated ClangFormatStyleOptions.rst by hand, is there a way to do that automatically instead (for future patches)?

[MyDeveloperDay]

In D60320#1457568, @reuk wrote:

I updated ClangFormatStyleOptions.rst by hand, is there a way to do that automatically instead (for future patches)?

I do it by hand, I know there is a python script out there, go with this for now, perhaps I'll try and find out how to do it automatically and then submit any differences if there are any (I'm sure there are some)

[MyDeveloperDay]

LGTM (minor nit)

clang/lib/Format/TokenAnnotator.cpp

2835–2836

nit: you don't need to {}

[reuk]

Fixed formatting nit.

[klimek]

lg

[reuk]

Closed by https://reviews.llvm.org/rG91f60b44958f, https://reviews.llvm.org/rL357908, https://reviews.llvm.org/rC357908 (sorry, I forgot to update the body of the commit message to close this automatically)

clang/docs/ClangFormatStyleOptions.rst

 **SpaceAfterCStyleCast** (``bool``)
   If ``true``, a space is inserted after C style casts.
 
   .. code-block:: c++
 
      true:                                  false:
      (int) i;                       vs.     (int)i;
 
+**SpaceAfterLogicalNot** (``bool``)
+  If ``true``, a space is inserted after the logical not operator (``!``).
+  .. code-block:: c++
+
+     true:                                  false:
+     ! someExpression();            vs.     !someExpression();
+
 **SpaceAfterTemplateKeyword** (``bool``)
   If ``true``, a space will be inserted after the 'template' keyword.
 
   .. code-block:: c++
 
      true:                                  false:
      template <int> void foo();     vs.     template<int> void foo();
 

clang/include/clang/Format/Format.h

 
   /// If ``true``, a space is inserted after C style casts.
   /// \code
   ///    true:                                  false:
   ///    (int) i;                       vs.     (int)i;
   /// \endcode
   bool SpaceAfterCStyleCast;
 
+  /// If ``true``, a space is inserted after the logical not operator (``!``).
+  /// \code
+  ///    true:                                  false:
+  ///    ! someExpression();            vs.     !someExpression();
+  /// \endcode
+  bool SpaceAfterLogicalNot;
+
   /// If \c true, a space will be inserted after the 'template' keyword.
   /// \code
   ///    true:                                  false:
   ///    template <int> void foo();     vs.     template<int> void foo();
   /// \endcode
   bool SpaceAfterTemplateKeyword;
 
   /// If ``false``, spaces will be removed before assignment operators.
enum SpaceBeforeParensOptions {
     ///    }
     /// \endcode
     SBPO_Always
   };
 
   /// Defines in which cases to put a space before opening parentheses.
   SpaceBeforeParensOptions SpaceBeforeParens;
 
   /// If ``false``, spaces will be removed before range-based for loop
   /// colon.
   /// \code
   ///    true:                                  false:
   ///    for (auto v : values) {}       vs.     for(auto v: values) {}
   /// \endcode
   bool SpaceBeforeRangeBasedForLoopColon;
 
   /// If ``true``, spaces may be inserted into ``()``.
return AccessModifierOffset == R.AccessModifierOffset &&
            PenaltyBreakString == R.PenaltyBreakString &&
            PenaltyExcessCharacter == R.PenaltyExcessCharacter &&
            PenaltyReturnTypeOnItsOwnLine == R.PenaltyReturnTypeOnItsOwnLine &&
            PenaltyBreakTemplateDeclaration ==
                R.PenaltyBreakTemplateDeclaration &&
            PointerAlignment == R.PointerAlignment &&
            RawStringFormats == R.RawStringFormats &&
            SpaceAfterCStyleCast == R.SpaceAfterCStyleCast &&
+           SpaceAfterLogicalNot == R.SpaceAfterLogicalNot &&
            SpaceAfterTemplateKeyword == R.SpaceAfterTemplateKeyword &&
            SpaceBeforeAssignmentOperators == R.SpaceBeforeAssignmentOperators &&
            SpaceBeforeCpp11BracedList == R.SpaceBeforeCpp11BracedList &&
            SpaceBeforeCtorInitializerColon ==
                R.SpaceBeforeCtorInitializerColon &&
            SpaceBeforeInheritanceColon == R.SpaceBeforeInheritanceColon &&
            SpaceBeforeParens == R.SpaceBeforeParens &&
            SpaceBeforeRangeBasedForLoopColon ==
                R.SpaceBeforeRangeBasedForLoopColon &&
            SpaceInEmptyParentheses == R.SpaceInEmptyParentheses &&
            SpacesBeforeTrailingComments == R.SpacesBeforeTrailingComments &&
            SpacesInAngles == R.SpacesInAngles &&
            SpacesInContainerLiterals == R.SpacesInContainerLiterals &&
            SpacesInCStyleCastParentheses == R.SpacesInCStyleCastParentheses &&
            SpacesInParentheses == R.SpacesInParentheses &&
            SpacesInSquareBrackets == R.SpacesInSquareBrackets &&

clang/lib/Format/Format.cpp

static void mapping(IO &IO, FormatStyle &Style) {
     IO.mapOptional("PenaltyReturnTypeOnItsOwnLine",
                    Style.PenaltyReturnTypeOnItsOwnLine);
     IO.mapOptional("PointerAlignment", Style.PointerAlignment);
     IO.mapOptional("RawStringFormats", Style.RawStringFormats);
     IO.mapOptional("ReflowComments", Style.ReflowComments);
     IO.mapOptional("SortIncludes", Style.SortIncludes);
     IO.mapOptional("SortUsingDeclarations", Style.SortUsingDeclarations);
     IO.mapOptional("SpaceAfterCStyleCast", Style.SpaceAfterCStyleCast);
+    IO.mapOptional("SpaceAfterLogicalNot", Style.SpaceAfterLogicalNot);
     IO.mapOptional("SpaceAfterTemplateKeyword",
                    Style.SpaceAfterTemplateKeyword);
     IO.mapOptional("SpaceBeforeAssignmentOperators",
                    Style.SpaceBeforeAssignmentOperators);
     IO.mapOptional("SpaceBeforeCpp11BracedList",
                    Style.SpaceBeforeCpp11BracedList);
     IO.mapOptional("SpaceBeforeCtorInitializerColon",
                    Style.SpaceBeforeCtorInitializerColon);
     IO.mapOptional("SpaceBeforeInheritanceColon",
                    Style.SpaceBeforeInheritanceColon);
     IO.mapOptional("SpaceBeforeParens", Style.SpaceBeforeParens);
     IO.mapOptional("SpaceBeforeRangeBasedForLoopColon",
                    Style.SpaceBeforeRangeBasedForLoopColon);
     IO.mapOptional("SpaceInEmptyParentheses", Style.SpaceInEmptyParentheses);
     IO.mapOptional("SpacesBeforeTrailingComments",
                    Style.SpacesBeforeTrailingComments);
     IO.mapOptional("SpacesInAngles", Style.SpacesInAngles);
     IO.mapOptional("SpacesInContainerLiterals",
                    Style.SpacesInContainerLiterals);
     IO.mapOptional("SpacesInCStyleCastParentheses",
FormatStyle getLLVMStyle(FormatStyle::LanguageKind Language) {
   LLVMStyle.UseTab = FormatStyle::UT_Never;
   LLVMStyle.ReflowComments = true;
   LLVMStyle.SpacesInParentheses = false;
   LLVMStyle.SpacesInSquareBrackets = false;
   LLVMStyle.SpaceInEmptyParentheses = false;
   LLVMStyle.SpacesInContainerLiterals = true;
   LLVMStyle.SpacesInCStyleCastParentheses = false;
   LLVMStyle.SpaceAfterCStyleCast = false;
+  LLVMStyle.SpaceAfterLogicalNot = false;
   LLVMStyle.SpaceAfterTemplateKeyword = true;
   LLVMStyle.SpaceBeforeCtorInitializerColon = true;
   LLVMStyle.SpaceBeforeInheritanceColon = true;
   LLVMStyle.SpaceBeforeParens = FormatStyle::SBPO_ControlStatements;
   LLVMStyle.SpaceBeforeRangeBasedForLoopColon = true;
   LLVMStyle.SpaceBeforeAssignmentOperators = true;
   LLVMStyle.SpaceBeforeCpp11BracedList = false;
   LLVMStyle.SpacesInAngles = false;

clang/lib/Format/TokenAnnotator.cpp

if (Right.is(TT_InlineASMColon) && Left.is(tok::coloncolon))
       return false;
     if (Right.is(TT_DictLiteral))
       return Style.SpacesInContainerLiterals;
     if (Right.is(TT_AttributeColon))
       return false;
     return true;
   }
   if (Left.is(TT_UnaryOperator))
-    return Right.is(TT_BinaryOperator);
+    return (Style.SpaceAfterLogicalNot && Left.is(tok::exclaim)) ||
+           Right.is(TT_BinaryOperator);
 
   // If the next token is a binary operator or a selector name, we have
   // incorrectly classified the parenthesis as a cast. FIXME: Detect correctly.
   if (Left.is(TT_CastRParen))
     return Style.SpaceAfterCStyleCast ||
            Right.isOneOf(TT_BinaryOperator, TT_SelectorName);
 
   if (Left.is(tok::greater) && Right.is(tok::greater)) {

clang/unittests/Format/FormatTest.cpp

TEST_F(FormatTest, ConfigurableSpaceBeforeParens) {
   verifyFormat("int f() throw (Deprecated);", SomeSpace);
   verifyFormat("typedef void (*cb) (int);", SomeSpace);
   verifyFormat("T A::operator()();", SomeSpace);
   verifyFormat("X A::operator++ (T);", SomeSpace);
   verifyFormat("int x = int (y);", SomeSpace);
   verifyFormat("auto lambda = []() { return 0; };", SomeSpace);
 }
 
+TEST_F(FormatTest, SpaceAfterLogicalNot) {
+  FormatStyle Spaces = getLLVMStyle();
+  Spaces.SpaceAfterLogicalNot = true;
+
+  verifyFormat("bool x = ! y", Spaces);
+  verifyFormat("if (! isFailure())", Spaces);
+  verifyFormat("if (! (a && b))", Spaces);
+  verifyFormat("\"Error!\"", Spaces);
+  verifyFormat("! ! x", Spaces);
+}
+
 TEST_F(FormatTest, ConfigurableSpacesInParentheses) {
   FormatStyle Spaces = getLLVMStyle();
 
   Spaces.SpacesInParentheses = true;
   verifyFormat("do_something( ::globalVar );", Spaces);
   verifyFormat("call( x, y, z );", Spaces);
   verifyFormat("call();", Spaces);
   verifyFormat("std::function<void( int, int )> callback;", Spaces);
TEST_F(FormatTest, ParsesConfiguration) {
   CHECK_PARSE("SpaceBeforeParens: NonEmptyParentheses", SpaceBeforeParens,
               FormatStyle::SBPO_NonEmptyParentheses);
   // For backward compatibility:
   CHECK_PARSE("SpaceAfterControlStatementKeyword: false", SpaceBeforeParens,
               FormatStyle::SBPO_Never);
   CHECK_PARSE("SpaceAfterControlStatementKeyword: true", SpaceBeforeParens,
               FormatStyle::SBPO_ControlStatements);
 
+  Style.SpaceAfterLogicalNot = false;
+  CHECK_PARSE("SpaceAfterLogicalNot: true", SpaceAfterLogicalNot,
+              true);
+  CHECK_PARSE("SpaceAfterLogicalNot: false", SpaceAfterLogicalNot,
+              false);
+
   Style.ColumnLimit = 123;
   FormatStyle BaseStyle = getLLVMStyle();
   CHECK_PARSE("BasedOnStyle: LLVM", ColumnLimit, BaseStyle.ColumnLimit);
   CHECK_PARSE("BasedOnStyle: LLVM\nColumnLimit: 1234", ColumnLimit, 1234u);
 
   Style.BreakBeforeBraces = FormatStyle::BS_Stroustrup;
   CHECK_PARSE("BreakBeforeBraces: Attach", BreakBeforeBraces,
               FormatStyle::BS_Attach);