Merge branch 'feature/issue_9437_defgroup' of https://github.com/albert-github/doxygen into albert-github-feature/issue_9437_defgroup

Author: doxygen

src/commentcnv.l

@@ -176,6 +176,7 @@ MAILADDR   ("mailto:")?[a-z_A-Z0-9\x80-\xff.+-]+"@"[a-z_A-Z0-9\x80-\xff-]+("."[a
 %x SkipString
 %x SkipVerbString
 %x SkipChar
+%x SkipLang
 %x SComment
 %x CComment
 %x CNComment
@@ -982,10 +983,44 @@ SLASHopt [/]*
 				     BEGIN(SkipString);
   				   }
    */
+<CComment,CNComment>{CMD}"~"[a-z_A-Z-]* { // language switch command
+                                     if (yyextra->lang!=SrcLangExt::Markdown) REJECT;
+                                     QCString langId = QCString(yytext).mid(2);
+                                     if (!langId.isEmpty() &&
+                                              qstricmp(Config_getEnumAsString(OUTPUT_LANGUAGE),langId)!=0)
+                                     { // enable language specific section
+                                       if (!Config_isAvailableEnum(OUTPUT_LANGUAGE,langId))
+                                       {
+                                         warn(yyextra->fileName,yyextra->lineNr,
+                                         "non supported language '{}' specified in '{}'",langId,QCString(yytext).stripWhiteSpace());
+                                       }
+                                       BEGIN(SkipLang);
+                                     }
+                                   }
 <CComment,CNComment>{CMD}{CMD}     |
 <CComment,CNComment>.	           {
                                      copyToOutput(yyscanner,yytext,yyleng);
   				   }
+<SkipLang>{CMD}"~"[a-zA-Z-]*       { /* language switch */
+                                     QCString langId(&yytext[2]);
+                                     if (!langId.isEmpty() && !Config_isAvailableEnum(OUTPUT_LANGUAGE,langId))
+                                     {
+                                        warn(yyextra->fileName,yyextra->lineNr,
+                                        "non supported language '{}' specified in '{}'",langId,QCString(yytext).stripWhiteSpace());
+                                     }
+                                     else if (langId.isEmpty() ||
+                                         qstricmp(Config_getEnumAsString(OUTPUT_LANGUAGE),langId)==0)
+                                     { // enable language specific section
+                                       BEGIN(CComment);
+                                     }
+                                   }
+<SkipLang>[^*@\\\n]*               { /* any character not a *, @, backslash or new line */
+                                   }
+<SkipLang>\n                       { /* new line in language block, needed for keeping track of line numbers */
+                                     copyToOutput(yyscanner,yytext,yyleng);
+                                   }
+<SkipLang>.                        { /* any other character */
+                                   }
 <SComment>^[ \t]*{CPPC}"/"{SLASHopt}/\n     {
   				     replaceComment(yyscanner,0);
   				   }

src/markdown.cpp

@@ -67,7 +67,7 @@ enum class ExplicitPageResult
 {
   explicitPage,      /**< docs start with a page command */
   explicitMainPage,  /**< docs start with a mainpage command */
-  explicitDirPage,   /**< docs start with a dir command */
+  explicitOtherPage, /**< docs start with a dir / defgroup / addtogroup command */
   notExplicit        /**< docs doesn't start with either page or mainpage */
 };
 
@@ -3434,6 +3434,31 @@ QCString Markdown::Private::processBlocks(std::string_view data,const size_t ind
   return out;
 }
 
+#define OPC(x) #x " ",#x "\n"
+static const StringVector otherPagingCmds = 
+{
+  OPC(dir), OPC(defgroup), OPC(addtogroup), OPC(weakgroup), OPC(ingroup),
+  OPC(fn), OPC(property), OPC(typedef), OPC(var), OPC(def),
+  OPC(enum), OPC(namespace), OPC(class), OPC(concept), OPC(module),
+  OPC(protocol), OPC(category), OPC(union), OPC(struct), OPC(interface),
+  OPC(idlexcept)
+};
+#undef OPC
+
+static bool literal_at_local(std::string_view data,const char *str)
+{
+  size_t len = strlen(str);
+  return len<=data.size() && data[0]==str[0] && qstrncmp(data.data()+1,str+1,len-1)==0;
+}
+
+static bool isOtherPage(std::string_view data)
+{
+  for (const auto &str : otherPagingCmds)
+  {
+    if (literal_at_local(data,str.c_str())) return true;
+  }
+  return false;
+}
 
 static ExplicitPageResult isExplicitPage(const QCString &docs)
 {
@@ -3471,13 +3496,10 @@ static ExplicitPageResult isExplicitPage(const QCString &docs)
         return ExplicitPageResult::explicitMainPage;
       }
     }
-    else if (i+1<size &&
-             (data[i]=='\\' || data[i]=='@') &&
-             (literal_at(data.substr(i+1),"dir\n") || literal_at(data.substr(i+1),"dir "))
-            )
+    else if (i+1<size && (data[i]=='\\' || data[i]=='@') && isOtherPage(data.substr(i+1)))
     {
-      AUTO_TRACE_EXIT("result=ExplicitPageResult::explicitDirPage");
-      return ExplicitPageResult::explicitDirPage;
+      AUTO_TRACE_EXIT("result=ExplicitPageResult::explicitOtherPage");
+      return ExplicitPageResult::explicitOtherPage;
     }
   }
   AUTO_TRACE_EXIT("result=ExplicitPageResult::notExplicit");
@@ -3629,6 +3651,7 @@ void MarkdownOutlineParser::parseInput(const QCString &fileName,
   current->docFile  = fileName;
   current->docLine  = 1;
   QCString docs = stripIndentation(fileBuf);
+  if (!docs.stripWhiteSpace().size()) return;
   Debug::print(Debug::Markdown,0,"======== Markdown =========\n---- input ------- \n{}\n",fileBuf);
   QCString id;
   Markdown markdown(fileName,1,0);
@@ -3721,7 +3744,7 @@ void MarkdownOutlineParser::parseInput(const QCString &fileName,
       break;
     case ExplicitPageResult::explicitMainPage:
       break;
-    case ExplicitPageResult::explicitDirPage:
+    case ExplicitPageResult::explicitOtherPage:
       break;
   }
   int lineNr=1;