[clang] adds `conceptDecl` as an ASTMatcher

[cjdb]

Summary

Closes #63934

[cjdb]

adds a header that wasn't a part of the original commit

[cjdb]

Apologies for the churn of reviewers, I've been struggling to find the most appropriate reviewer for this CL.

[aaron.ballman]

Just some nits, but mostly looks good. Can you also run clang/docs/tools/dump_ast_matchers.py to regenerate the public documentation?

clang/docs/ReleaseNotes.rst

248

You should mention the name of the matcher you've added so there's a bit more context to the release note.

clang/include/clang/ASTMatchers/ASTMatchers.h

1339

This comment isn't quite complete/correct.

[cjdb]

applies feedback

[cjdb]

In D155549#4515598, @aaron.ballman wrote:

Just some nits, but mostly looks good. Can you also run clang/docs/tools/dump_ast_matchers.py to regenerate the public documentation?

Currently getting this, but I got quite a few changes nonetheless. Is that a concern?

*** Unparsable: " template <typename NodeType> using AstTypeMatcher = internal::VariadicDynCastAllOfMatcher<Type, NodeType>;" ***
*** Unparsable: " } // namespace ast_matchers } // namespace clang " ***

[aaron.ballman]

In D155549#4516852, @cjdb wrote:

In D155549#4515598, @aaron.ballman wrote:

Just some nits, but mostly looks good. Can you also run clang/docs/tools/dump_ast_matchers.py to regenerate the public documentation?

Currently getting this, but I got quite a few changes nonetheless. Is that a concern?

*** Unparsable: " template <typename NodeType> using AstTypeMatcher = internal::VariadicDynCastAllOfMatcher<Type, NodeType>;" ***
*** Unparsable: " } // namespace ast_matchers } // namespace clang " ***

Not a concern you need to worry about. LGTM!

[cjdb]

just trying to get CI close to green :)

clang/docs/LibASTMatchersReference.html

 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Decl.html">Decl</a>&gt;</td><td class="name" onclick="toggle('conceptDecl0')"><a name="conceptDecl0Anchor">conceptDecl</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1ConceptDecl.html">ConceptDecl</a>&gt;...</td></tr>
+<tr><td colspan="4" class="doc" id="conceptDecl0"><pre>Matches concept declarations.
+
+Example matches integral
+  template&lt;typename T&gt;
+  concept integral = std::is_integral_v&lt;T&gt;;
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Decl.html">Decl</a>&gt;</td><td class="name" onclick="toggle('cxxConstructorDecl0')"><a name="cxxConstructorDecl0Anchor">cxxConstructorDecl</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CXXConstructorDecl.html">CXXConstructorDecl</a>&gt;...</td></tr>
 <tr><td colspan="4" class="doc" id="cxxConstructorDecl0"><pre>Matches C++ constructor declarations.
 

 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt;</td><td class="name" onclick="toggle('coroutineBodyStmt0')"><a name="coroutineBodyStmt0Anchor">coroutineBodyStmt</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CoroutineBodyStmt.html">CoroutineBodyStmt</a>&gt;...</td></tr>
+<tr><td colspan="4" class="doc" id="coroutineBodyStmt0"><pre>Matches coroutine body statements.
+
+coroutineBodyStmt() matches the coroutine below
+  generator&lt;int&gt; gen() {
+    co_return;
+  }
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt;</td><td class="name" onclick="toggle('coyieldExpr0')"><a name="coyieldExpr0Anchor">coyieldExpr</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CoyieldExpr.html">CoyieldExpr</a>&gt;...</td></tr>
 <tr><td colspan="4" class="doc" id="coyieldExpr0"><pre>Matches co_yield expressions.
 

 
 
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CXXConstructExpr.html">CXXConstructExpr</a>&gt;</td><td class="name" onclick="toggle('argumentCountAtLeast1')"><a name="argumentCountAtLeast1Anchor">argumentCountAtLeast</a></td><td>unsigned N</td></tr>
-<tr><td colspan="4" class="doc" id="argumentCountAtLeast1"><pre>Checks that a call expression or a constructor call expression has
-at least the specified number of arguments (including absent default arguments).
+<tr><td colspan="4" class="doc" id="argumentCountAtLeast1"><pre>Checks that a call expression or a constructor call expression has at least
+the specified number of arguments (including absent default arguments).
 
-Example matches f(0, 0) and g(0, 0, 0) (matcher = callExpr(argumentCountAtLeast(2)))
+Example matches f(0, 0) and g(0, 0, 0)
+(matcher = callExpr(argumentCountAtLeast(2)))
   void f(int x, int y);
   void g(int x, int y, int z);
   f(0, 0);

 
 
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CXXUnresolvedConstructExpr.html">CXXUnresolvedConstructExpr</a>&gt;</td><td class="name" onclick="toggle('argumentCountAtLeast2')"><a name="argumentCountAtLeast2Anchor">argumentCountAtLeast</a></td><td>unsigned N</td></tr>
-<tr><td colspan="4" class="doc" id="argumentCountAtLeast2"><pre>Checks that a call expression or a constructor call expression has
-at least the specified number of arguments (including absent default arguments).
+<tr><td colspan="4" class="doc" id="argumentCountAtLeast2"><pre>Checks that a call expression or a constructor call expression has at least
+the specified number of arguments (including absent default arguments).
 
-Example matches f(0, 0) and g(0, 0, 0) (matcher = callExpr(argumentCountAtLeast(2)))
+Example matches f(0, 0) and g(0, 0, 0)
+(matcher = callExpr(argumentCountAtLeast(2)))
   void f(int x, int y);
   void g(int x, int y, int z);
   f(0, 0);

 
 
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CallExpr.html">CallExpr</a>&gt;</td><td class="name" onclick="toggle('argumentCountAtLeast0')"><a name="argumentCountAtLeast0Anchor">argumentCountAtLeast</a></td><td>unsigned N</td></tr>
-<tr><td colspan="4" class="doc" id="argumentCountAtLeast0"><pre>Checks that a call expression or a constructor call expression has
-at least the specified number of arguments (including absent default arguments).
+<tr><td colspan="4" class="doc" id="argumentCountAtLeast0"><pre>Checks that a call expression or a constructor call expression has at least
+the specified number of arguments (including absent default arguments).
 
-Example matches f(0, 0) and g(0, 0, 0) (matcher = callExpr(argumentCountAtLeast(2)))
+Example matches f(0, 0) and g(0, 0, 0)
+(matcher = callExpr(argumentCountAtLeast(2)))
   void f(int x, int y);
   void g(int x, int y, int z);
   f(0, 0);

 
 
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1ObjCMessageExpr.html">ObjCMessageExpr</a>&gt;</td><td class="name" onclick="toggle('argumentCountAtLeast3')"><a name="argumentCountAtLeast3Anchor">argumentCountAtLeast</a></td><td>unsigned N</td></tr>
-<tr><td colspan="4" class="doc" id="argumentCountAtLeast3"><pre>Checks that a call expression or a constructor call expression has
-at least the specified number of arguments (including absent default arguments).
+<tr><td colspan="4" class="doc" id="argumentCountAtLeast3"><pre>Checks that a call expression or a constructor call expression has at least
+the specified number of arguments (including absent default arguments).
 
-Example matches f(0, 0) and g(0, 0, 0) (matcher = callExpr(argumentCountAtLeast(2)))
+Example matches f(0, 0) and g(0, 0, 0)
+(matcher = callExpr(argumentCountAtLeast(2)))
   void f(int x, int y);
   void g(int x, int y, int z);
   f(0, 0);

 
 
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CXXForRangeStmt.html">CXXForRangeStmt</a>&gt;</td><td class="name" onclick="toggle('hasBody3')"><a name="hasBody3Anchor">hasBody</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt; InnerMatcher</td></tr>
-<tr><td colspan="4" class="doc" id="hasBody3"><pre>Matches a 'for', 'while', 'do' statement or a function definition that has
-a given body. Note that in case of functions this matcher only matches the
-definition itself and not the other declarations of the same function.
+<tr><td colspan="4" class="doc" id="hasBody3"><pre>Matches a 'for', 'while', 'while' statement or a function or coroutine
+definition that has a given body. Note that in case of functions or
+coroutines this matcher only matches the definition itself and not the
+other declarations of the same function or coroutine.
 
 Given
   for (;;) {}

 </pre></td></tr>
 
 
+<tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1CoroutineBodyStmt.html">CoroutineBodyStmt</a>&gt;</td><td class="name" onclick="toggle('hasBody5')"><a name="hasBody5Anchor">hasBody</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt; InnerMatcher</td></tr>
+<tr><td colspan="4" class="doc" id="hasBody5"><pre>Matches a 'for', 'while', 'while' statement or a function or coroutine
+definition that has a given body. Note that in case of functions or
+coroutines this matcher only matches the definition itself and not the
+other declarations of the same function or coroutine.
+
+Given
+  for (;;) {}
+forStmt(hasBody(compoundStmt()))
+  matches 'for (;;) {}'
+with compoundStmt()
+  matching '{}'
+
+Given
+  void f();
+  void f() {}
+functionDecl(hasBody(compoundStmt()))
+  matches 'void f() {}'
+with compoundStmt()
+  matching '{}'
+  but does not match 'void f();'
+</pre></td></tr>
+
+
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1DecayedType.html">DecayedType</a>&gt;</td><td class="name" onclick="toggle('hasDecayedType0')"><a name="hasDecayedType0Anchor">hasDecayedType</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1QualType.html">QualType</a>&gt; InnerType</td></tr>
 <tr><td colspan="4" class="doc" id="hasDecayedType0"><pre>Matches the decayed type, whoes decayed type matches InnerMatcher
 </pre></td></tr>

 
 
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1DoStmt.html">DoStmt</a>&gt;</td><td class="name" onclick="toggle('hasBody0')"><a name="hasBody0Anchor">hasBody</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt; InnerMatcher</td></tr>
-<tr><td colspan="4" class="doc" id="hasBody0"><pre>Matches a 'for', 'while', 'do' statement or a function definition that has
-a given body. Note that in case of functions this matcher only matches the
-definition itself and not the other declarations of the same function.
+<tr><td colspan="4" class="doc" id="hasBody0"><pre>Matches a 'for', 'while', 'while' statement or a function or coroutine
+definition that has a given body. Note that in case of functions or
+coroutines this matcher only matches the definition itself and not the
+other declarations of the same function or coroutine.
 
 Given
   for (;;) {}

 
 
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1ForStmt.html">ForStmt</a>&gt;</td><td class="name" onclick="toggle('hasBody1')"><a name="hasBody1Anchor">hasBody</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt; InnerMatcher</td></tr>
-<tr><td colspan="4" class="doc" id="hasBody1"><pre>Matches a 'for', 'while', 'do' statement or a function definition that has
-a given body. Note that in case of functions this matcher only matches the
-definition itself and not the other declarations of the same function.
+<tr><td colspan="4" class="doc" id="hasBody1"><pre>Matches a 'for', 'while', 'while' statement or a function or coroutine
+definition that has a given body. Note that in case of functions or
+coroutines this matcher only matches the definition itself and not the
+other declarations of the same function or coroutine.
 
 Given
   for (;;) {}

 
 
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1FunctionDecl.html">FunctionDecl</a>&gt;</td><td class="name" onclick="toggle('hasBody4')"><a name="hasBody4Anchor">hasBody</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt; InnerMatcher</td></tr>
-<tr><td colspan="4" class="doc" id="hasBody4"><pre>Matches a 'for', 'while', 'do' statement or a function definition that has
-a given body. Note that in case of functions this matcher only matches the
-definition itself and not the other declarations of the same function.
+<tr><td colspan="4" class="doc" id="hasBody4"><pre>Matches a 'for', 'while', 'while' statement or a function or coroutine
+definition that has a given body. Note that in case of functions or
+coroutines this matcher only matches the definition itself and not the
+other declarations of the same function or coroutine.
 
 Given
   for (;;) {}

 
 
 <tr><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1WhileStmt.html">WhileStmt</a>&gt;</td><td class="name" onclick="toggle('hasBody2')"><a name="hasBody2Anchor">hasBody</a></td><td>Matcher&lt;<a href="https://clang.llvm.org/doxygen/classclang_1_1Stmt.html">Stmt</a>&gt; InnerMatcher</td></tr>
-<tr><td colspan="4" class="doc" id="hasBody2"><pre>Matches a 'for', 'while', 'do' statement or a function definition that has
-a given body. Note that in case of functions this matcher only matches the
-definition itself and not the other declarations of the same function.
+<tr><td colspan="4" class="doc" id="hasBody2"><pre>Matches a 'for', 'while', 'while' statement or a function or coroutine
+definition that has a given body. Note that in case of functions or
+coroutines this matcher only matches the definition itself and not the
+other declarations of the same function or coroutine.
 
 Given
   for (;;) {}

clang/docs/ReleaseNotes.rst

 - Added ``__builtin_elementwise_nearbyint`` for floating point
   types. This allows access to ``llvm.nearbyint`` for arbitrary
   floating-point and vector of floating-point types.
+- Clang AST matcher now matches concept declarations with `conceptDecl`.
 
 New Compiler Flags
 ------------------

clang/include/clang/ASTMatchers/ASTMatchers.h

 extern const internal::VariadicDynCastAllOfMatcher<Decl, CXXDeductionGuideDecl>
     cxxDeductionGuideDecl;
 
+/// Matches concept declarations.
+///
+/// Example matches integral
+/// \code
+///   template<typename T>
+///   concept integral = std::is_integral_v<T>;
+/// \endcode
+extern const internal::VariadicDynCastAllOfMatcher<Decl, ConceptDecl>
+    conceptDecl;
+
 /// Matches variable declarations.
 ///
 /// Note: this does not match declarations of member variables, which are

clang/lib/ASTMatchers/ASTMatchersInternal.cpp

 const internal::VariadicDynCastAllOfMatcher<Decl, CXXMethodDecl> cxxMethodDecl;
 const internal::VariadicDynCastAllOfMatcher<Decl, CXXConversionDecl>
     cxxConversionDecl;
+const internal::VariadicDynCastAllOfMatcher<Decl, ConceptDecl> conceptDecl;
 const internal::VariadicDynCastAllOfMatcher<Decl, VarDecl> varDecl;
 const internal::VariadicDynCastAllOfMatcher<Decl, FieldDecl> fieldDecl;
 const internal::VariadicDynCastAllOfMatcher<Decl, IndirectFieldDecl>

clang/lib/ASTMatchers/Dynamic/Registry.cpp

   REGISTER_MATCHER(compoundLiteralExpr);
   REGISTER_MATCHER(compoundStmt);
   REGISTER_MATCHER(coawaitExpr);
+  REGISTER_MATCHER(conceptDecl);
   REGISTER_MATCHER(conditionalOperator);
   REGISTER_MATCHER(constantArrayType);
   REGISTER_MATCHER(constantExpr);

clang/unittests/AST/DeclTest.cpp

 
 #include "clang/AST/Decl.h"
 #include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclTemplate.h"
 #include "clang/AST/Mangle.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 #include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/Basic/Diagnostic.h"
 #include "clang/Basic/LLVM.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Lex/Lexer.h"

   ASSERT_TRUE(0 == MangleB.compare("_ZTSAT0__T_"));
 }
 
+TEST(Decl, ConceptDecl) {
+  llvm::StringRef Code(R"(
+    template<class T>
+    concept integral = __is_integral(T);
+  )");
+
+  auto AST = tooling::buildASTFromCodeWithArgs(Code, {"-std=c++20"});
+  ASTContext &Ctx = AST->getASTContext();
+  SourceManager &SM = Ctx.getSourceManager();
+
+  const auto *Decl =
+      selectFirst<ConceptDecl>("decl", match(conceptDecl().bind("decl"), Ctx));
+  ASSERT_TRUE(Decl != nullptr);
+  EXPECT_EQ(Decl->getName(), "integral");
+}
+
 TEST(Decl, EnumDeclRange) {
   llvm::Annotations Code(R"(
     typedef int Foo;