Merge branch 'ignore-empty-doxygen-commands'

* ignore-empty-doxygen-commands:
  Fix incorrect warning "Unknown Doxygen command: ."
  Don't use invalid iterators in Doxygen command parsing code

Conflicts:
	CHANGES.current

CHANGES.current

@@ -7,6 +7,9 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.1.0 (in progress)
 ===========================
 
+2021-03-01: vadz
+            #1952 Fix incorrect warning "Unknown Doxygen command: ."
+
 2021-02-28: p2k
             #969 [Javascript] v8/node - prevent crash calling a constructor without new keyword.
 

Examples/test-suite/doxygen_parsing.i

@@ -29,6 +29,7 @@ enum SomeEnum
  */
 struct SomeStruct
 {
+   int width; ///< \**immutable** image width in pixels
 };
 
 /**

Examples/test-suite/java/doxygen_parsing_runme.java

@@ -45,6 +45,12 @@ public class doxygen_parsing_runme {
     		" The struct comment \n" +
     		" \n" +
     		"");
+    wantedComments.put("doxygen_parsing.SomeStruct.setWidth(int)",
+    		"**immutable** image width in pixels \n" +
+    		"");
+    wantedComments.put("doxygen_parsing.SomeStruct.getWidth()",
+    		"**immutable** image width in pixels \n" +
+    		"");
     wantedComments.put("doxygen_parsing.doxygen_parsing.setSomeVar(int)",
     		" The var comment \n" +
     		" \n" +

Source/Doxygen/doxyparser.cxx

@@ -1081,6 +1081,13 @@ bool DoxygenParser::addDoxyCommand(DoxygenParser::TokenList &tokList, const std:
     tokList.push_back(Token(COMMAND, cmd));
     return true;
   } else {
+    if (cmd.empty()) {
+      // This actually indicates a bug in the code in this file, as this
+      // function shouldn't be called at all in this case.
+      printListError(WARN_DOXYGEN_UNKNOWN_COMMAND, "Unexpected empty Doxygen command.");
+      return false;
+    }
+
     // This function is called for the special Doxygen commands, but also for
     // HTML commands (or anything that looks like them, actually) and entities.
     // We don't recognize all of those, so just ignore them and pass them
@@ -1181,6 +1188,11 @@ void DoxygenParser::processWordCommands(size_t &pos, const std::string &line) {
   size_t endOfWordPos = getEndOfWordCommand(line, pos);
 
   string cmd = line.substr(pos, endOfWordPos - pos);
+  if (cmd.empty()) {
+    // This was a bare backslash, just ignore it.
+    return;
+  }
+
   addDoxyCommand(m_tokenList, cmd);
 
   // A flag for whether we want to skip leading spaces after the command