[Clang][Comments] Make @relates an inline comment command (llvm#115040)

According to the Doxygen documentation,
the `relates`, `related`, `relatesalso`, and `relatedalso` commands all
have a single argument. This patch changes their classification from
`VerbatimLineCommand` to `InlineCommand` so the argument is correctly
parsed.

Author: sdkrystian

clang/docs/ReleaseNotes.rst

@@ -662,6 +662,8 @@ Bug Fixes to AST Handling
 - Fixed a crash that occurred when dividing by zero in complex integer division. (#GH55390).
 - Fixed a bug in ``ASTContext::getRawCommentForAnyRedecl()`` where the function could
   sometimes incorrectly return null even if a comment was present. (#GH108145)
+- Clang now correctly parses the argument of the ``relates``, ``related``, ``relatesalso``,
+  and ``relatedalso`` comment commands.
 
 Miscellaneous Bug Fixes
 ^^^^^^^^^^^^^^^^^^^^^^^

clang/include/clang/AST/CommentCommands.td

@@ -111,6 +111,11 @@ def Extends    : InlineCommand<"extends">;
 def Implements : InlineCommand<"implements">;
 def MemberOf   : InlineCommand<"memberof">;
 
+def Relates     : InlineCommand<"relates">;
+def Related     : InlineCommand<"related">;
+def RelatesAlso : InlineCommand<"relatesalso">;
+def RelatedAlso : InlineCommand<"relatedalso">;
+
 //===----------------------------------------------------------------------===//
 // BlockCommand
 //===----------------------------------------------------------------------===//
@@ -248,11 +253,6 @@ def Page     : VerbatimLineCommand<"page">;
 def Mainpage : VerbatimLineCommand<"mainpage">;
 def Subpage  : VerbatimLineCommand<"subpage">;
 
-def Relates     : VerbatimLineCommand<"relates">;
-def Related     : VerbatimLineCommand<"related">;
-def RelatesAlso : VerbatimLineCommand<"relatesalso">;
-def RelatedAlso : VerbatimLineCommand<"relatedalso">;
-
 def AddIndex : VerbatimLineCommand<"addindex">;
 
 // These take a single argument mostly, but since they include a file they'll

clang/test/AST/ast-dump-comment.cpp

@@ -73,6 +73,11 @@ int Test_InlineCommandCommentAnchor;
 // CHECK:      VarDecl{{.*}}Test_InlineCommandComment
 // CHECK:        InlineCommandComment{{.*}} Name="anchor" RenderAnchor Arg[0]="Aaa"
 
+/// \relates Aaa
+int Test_InlineCommandCommentRelates;
+// CHECK:      VarDecl{{.*}}Test_InlineCommandCommentRelates
+// CHECK:        InlineCommandComment{{.*}} Name="relates" RenderNormal Arg[0]="Aaa"
+
 /// <a>Aaa</a>
 /// <br/>
 int Test_HTMLTagComment;