diff --git a/clang/docs/ClangFormatStyleOptions.rst b/clang/docs/ClangFormatStyleOptions.rst
--- a/clang/docs/ClangFormatStyleOptions.rst
+++ b/clang/docs/ClangFormatStyleOptions.rst
@@ -3861,6 +3861,35 @@
+**RequiresExpressionIndentation** (``RequiresExpressionIndentationKind``) :versionbadge:`clang-format 16`
+ The indentation used for requires expression bodies.
+
+ Possible values:
+
+ * ``REI_OuterScope`` (in configuration: ``OuterScope``)
+ Align requires expression body relative to the indentation level of the
+ outer scope the requires expression resides in.
+ This is the default.
+
+ .. code-block:: c++
+
+ template <typename T>
+ concept C = requires(T t) {
+ ...
+ }
+
+ * ``REI_Keyword`` (in configuration: ``Keyword``)
+ Align requires expression body relative to the `requires` keyword.
+
+ .. code-block:: c++
+
+ template <typename T>
+ concept C = requires(T t) {
+ ...
+ }
+
+
+
**SeparateDefinitionBlocks** (``SeparateDefinitionStyle``) :versionbadge:`clang-format 14`
Specifies the use of empty lines to separate definition blocks, including
classes, structs, enums, and functions.
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -537,7 +537,10 @@
clang-format
------------
-- Add `RemoveSemicolon` option for removing `;` after a non-empty function definition.
+- Add ``RemoveSemicolon`` option for removing ``;`` after a non-empty function definition.
+- Add ``RequiresExpressionIndentation`` option for configuring the alignment of requires-expressions.
+ The default value of this option is ``OuterScope``, which differs in behavior from clang-format 15.
+ To match the default behavior of clang-format 15, use the ``Keyword`` value.
clang-extdef-mapping
--------------------
diff --git a/clang/include/clang/Format/Format.h b/clang/include/clang/Format/Format.h
--- a/clang/include/clang/Format/Format.h
+++ b/clang/include/clang/Format/Format.h
@@ -3153,6 +3153,32 @@
/// \version 15
RequiresClausePositionStyle RequiresClausePosition;
+ /// Indentation logic for requires expression bodies.
+ enum RequiresExpressionIndentationKind : int8_t {
+ /// Align requires expression body relative to the indentation level of the
+ /// outer scope the requires expression resides in.
+ /// This is the default.
+ /// \code
+ /// template <typename T>
+ /// concept C = requires(T t) {
+ /// ...
+ /// }
+ /// \endcode
+ REI_OuterScope,
+ /// Align requires expression body relative to the `requires` keyword.
+ /// \code
+ /// template <typename T>
+ /// concept C = requires(T t) {
+ /// ...
+ /// }
+ /// \endcode
+ REI_Keyword,
+ };
+
+ /// The indentation used for requires expression bodies.
+ /// \version 16
+ RequiresExpressionIndentationKind RequiresExpressionIndentation;
+
/// \brief The style if definition blocks should be separated.
enum SeparateDefinitionStyle : int8_t {
/// Leave definition blocks as they are.
@@ -3988,6 +4014,7 @@
RemoveBracesLLVM == R.RemoveBracesLLVM &&
RemoveSemicolon == R.RemoveSemicolon &&
RequiresClausePosition == R.RequiresClausePosition &&
+ RequiresExpressionIndentation == R.RequiresExpressionIndentation &&
SeparateDefinitionBlocks == R.SeparateDefinitionBlocks &&
ShortNamespaceLines == R.ShortNamespaceLines &&
SortIncludes == R.SortIncludes &&
diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -1403,8 +1403,10 @@
CurrentState.NestedBlockIndent = State.Column + Current.ColumnWidth + 1;
if (Current.isOneOf(TT_LambdaLSquare, TT_LambdaArrow))
CurrentState.LastSpace = State.Column;
- if (Current.is(TT_RequiresExpression))
+ if (Current.is(TT_RequiresExpression) &&
+ Style.RequiresExpressionIndentation == FormatStyle::REI_Keyword) {
CurrentState.NestedBlockIndent = State.Column;
+ }
// Insert scopes created by fake parenthesis.
const FormatToken *Previous = Current.getPreviousNonComment();
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -99,6 +99,15 @@
}
};
+template <>
+struct ScalarEnumerationTraits<FormatStyle::RequiresExpressionIndentationKind> {
+ static void
+ enumeration(IO &IO, FormatStyle::RequiresExpressionIndentationKind &Value) {
+ IO.enumCase(Value, "Keyword", FormatStyle::REI_Keyword);
+ IO.enumCase(Value, "OuterScope", FormatStyle::REI_OuterScope);
+ }
+};
+
template <> struct ScalarEnumerationTraits<FormatStyle::UseTabStyle> {
static void enumeration(IO &IO, FormatStyle::UseTabStyle &Value) {
IO.enumCase(Value, "Never", FormatStyle::UT_Never);
@@ -854,6 +863,8 @@
IO.mapOptional("RemoveBracesLLVM", Style.RemoveBracesLLVM);
IO.mapOptional("RemoveSemicolon", Style.RemoveSemicolon);
IO.mapOptional("RequiresClausePosition", Style.RequiresClausePosition);
+ IO.mapOptional("RequiresExpressionIndentation",
+ Style.RequiresExpressionIndentation);
IO.mapOptional("SeparateDefinitionBlocks", Style.SeparateDefinitionBlocks);
IO.mapOptional("ShortNamespaceLines", Style.ShortNamespaceLines);
IO.mapOptional("SortIncludes", Style.SortIncludes);
@@ -1290,6 +1301,7 @@
LLVMStyle.PointerAlignment = FormatStyle::PAS_Right;
LLVMStyle.ReferenceAlignment = FormatStyle::RAS_Pointer;
LLVMStyle.RequiresClausePosition = FormatStyle::RCPS_OwnLine;
+ LLVMStyle.RequiresExpressionIndentation = FormatStyle::REI_Keyword;
LLVMStyle.SeparateDefinitionBlocks = FormatStyle::SDS_Leave;
LLVMStyle.ShortNamespaceLines = 1;
LLVMStyle.SpacesBeforeTrailingComments = 1;
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -24995,6 +24995,123 @@
"bar(requires);");
}
+TEST_F(FormatTest, RequiresExpressionIndentation) {
+ auto Style = getLLVMStyle();
+ EXPECT_EQ(Style.RequiresExpressionIndentation, FormatStyle::REI_Keyword);
+
+ verifyFormat("template <typename T>\n"
+ "concept C = requires(T t) {\n"
+ " typename T::value;\n"
+ " requires requires(typename T::value v) {\n"
+ " { t == v } -> std::same_as<bool>;\n"
+ " };\n"
+ " };",
+ Style);
+
+ verifyFormat(
+ "template <typename T>\n"
+ "void bar(T)\n"
+ " requires Foo<T> && requires(T t) {\n"
+ " { t.foo() } -> std::same_as<int>;\n"
+ " } && requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " --t;\n"
+ " };",
+ Style);
+
+ verifyFormat("template <typename T>\n"
+ " requires Foo<T> &&\n"
+ " requires(T t) {\n"
+ " { t.foo() } -> std::same_as<int>;\n"
+ " } && requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " --t;\n"
+ " }\n"
+ "void bar(T);",
+ Style);
+
+ verifyFormat("template <typename T> void f() {\n"
+ " if constexpr (requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " }) {\n"
+ " }\n"
+ "}",
+ Style);
+
+ verifyFormat(
+ "template <typename T> void f() {\n"
+ " if constexpr (condition && requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " }) {\n"
+ " }\n"
+ "}",
+ Style);
+
+ verifyFormat("template <typename T> struct C {\n"
+ " void f()\n"
+ " requires requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " };\n"
+ "};",
+ Style);
+
+ Style.RequiresExpressionIndentation = FormatStyle::REI_OuterScope;
+
+ verifyFormat("template <typename T>\n"
+ "concept C = requires(T t) {\n"
+ " typename T::value;\n"
+ " requires requires(typename T::value v) {\n"
+ " { t == v } -> std::same_as<bool>;\n"
+ " };\n"
+ "};",
+ Style);
+
+ verifyFormat("template <typename T>\n"
+ "void bar(T)\n"
+ " requires Foo<T> && requires(T t) {\n"
+ " { t.foo() } -> std::same_as<int>;\n"
+ " } && requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " --t;\n"
+ " };",
+ Style);
+
+ verifyFormat("template <typename T>\n"
+ " requires Foo<T> &&\n"
+ " requires(T t) {\n"
+ " { t.foo() } -> std::same_as<int>;\n"
+ " } && requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " --t;\n"
+ " }\n"
+ "void bar(T);",
+ Style);
+
+ verifyFormat("template <typename T> void f() {\n"
+ " if constexpr (requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " }) {\n"
+ " }\n"
+ "}",
+ Style);
+
+ verifyFormat("template <typename T> void f() {\n"
+ " if constexpr (condition && requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " }) {\n"
+ " }\n"
+ "}",
+ Style);
+
+ verifyFormat("template <typename T> struct C {\n"
+ " void f()\n"
+ " requires requires(T t) {\n"
+ " { t.bar() } -> std::same_as<bool>;\n"
+ " };\n"
+ "};",
+ Style);
+}
+
TEST_F(FormatTest, StatementAttributeLikeMacros) {
FormatStyle Style = getLLVMStyle();
StringRef Source = "void Foo::slot() {\n"