Python -flatstaticmethod corrections

Correct logic for suppressing static methods.
Previous logic was missing director disown methods.
Add changes file entry for -flatstaticmethod.

Closes #2137

CHANGES.current

@@ -7,6 +7,20 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.1.0 (in progress)
 ===========================
 
+2022-03-21: jschueller, jim-easterbrook, wsfulton
+            [Python] #2137 C++ static member functions no longer generate a "flattened"
+            name in the Python module. For example:
+
+              s = example.Spam()
+              s.foo()               # Spam::foo() via an instance
+              example.Spam.foo()    # Spam::foo() using class method
+              example.Spam_foo()    # Spam::foo() "flattened" name
+
+            The "flattened" name is no longer generated, but can be generated
+            by using the new -flatstaticmethod option.
+
+            *** POTENTIAL INCOMPATIBILITY ***
+
 2022-03-17: olly
 	    [Python] #1779 SWIG's Python test-suite and examples are now
 	    run with Python 3 by default.  To run them with Python 2, set

Doc/Manual/Python.html

@@ -957,7 +957,7 @@ swig -python -help
 <tr><td>-doxygen        </td><td>Convert C++ doxygen comments to pydoc comments in proxy classes</td></tr>
 <tr><td>-extranative    </td><td>Return extra native wrappers for C++ std containers wherever possible</td></tr>
 <tr><td>-fastproxy      </td><td>Use fast proxy mechanism for member methods</td></tr>
-<tr><td>-flatstaticmethod </td><td>Generate Foo_bar for static method Foo::bar</td></tr>
+<tr><td>-flatstaticmethod </td><td>Generate additional flattened Python methods for C++ static methods</td></tr>
 <tr><td>-globals &lt;name&gt; </td><td>Set &lt;name&gt; used to access C global variable (default: 'cvar')</td></tr>
 <tr><td>-interface &lt;mod&gt;</td><td>Set low-level C/C++ module name to &lt;mod&gt; (default: module name prefixed by '_')</td></tr>
 <tr><td>-keyword        </td><td>Use keyword arguments</td></tr>
@@ -1626,6 +1626,8 @@ In Python, the static member can be accessed in three different ways:
 
 <p>
 The last technique is only available when using the <tt>-flatstaticmethod</tt> option.
+This option is not recommended, it is only available for backwards compatibility
+as ancient versions of Python did not have Python class methods.
 </p>
 
 <p>

Source/Modules/python.cxx

@@ -119,7 +119,7 @@ Python Options (available with -python)\n\
      -doxygen        - Convert C++ doxygen comments to pydoc comments in proxy classes\n\
      -extranative    - Return extra native wrappers for C++ std containers wherever possible\n\
      -fastproxy      - Use fast proxy mechanism for member methods\n\
-     -flatstaticmethod         - Generate Foo_bar for static method Foo::bar\n\
+     -flatstaticmethod         - Generate additional flattened Python methods for C++ static methods\n\
      -globals <name> - Set <name> used to access C global variable (default: 'cvar')\n\
      -interface <mod>- Set low-level C/C++ module name to <mod> (default: module name prefixed by '_')\n\
      -keyword        - Use keyword arguments\n";
@@ -2645,7 +2645,7 @@ public:
       add_method(symname, wname, 0, p);
 
     /* Create a shadow for this function (if enabled and not in a member function) */
-    if (!builtin && (shadow) && (!(shadow & PYSHADOW_MEMBER)) && (use_static_method)) {
+    if (!builtin && shadow && (!(shadow & PYSHADOW_MEMBER)) && use_static_method) {
       emitFunctionShadowHelper(n, in_class ? f_shadow_stubs : f_shadow, symname, 0);
     }
     DelWrapper(f);
@@ -3312,14 +3312,14 @@ public:
       Wrapper_print(f, f_wrappers);
     }
 
-    bool use_static_method = flat_static_method || !in_class || constructor || (Cmp(storage, "friend") == 0);
+    bool use_static_method = flat_static_method || !Swig_storage_isstatic_custom(n, "staticmemberfunctionHandler:storage");
     /* Now register the function with the interpreter.   */
     if (!Getattr(n, "sym:overloaded")) {
       if (!builtin_self && (use_static_method || !builtin))
 	add_method(iname, wname, allow_kwargs, n, funpack, num_required, num_arguments);
 
       /* Create a shadow for this function (if enabled and not in a member function) */
-      if (!builtin && (shadow) && (!(shadow & PYSHADOW_MEMBER)) && (use_static_method)) {
+      if (!builtin && shadow && (!(shadow & PYSHADOW_MEMBER)) && use_static_method) {
 	emitFunctionShadowHelper(n, in_class ? f_shadow_stubs : f_shadow, iname, allow_kwargs);
       }
     } else {