[perl] Fix C++11 enum class wrapping with -const

Fixes #630

CHANGES.current

@@ -7,6 +7,10 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.3.0 (in progress)
 ===========================
 
+2024-09-11: olly
+	    [Perl] #630 Fix wrapping of C++11 enum class when -const command line
+	    option is specified.
+
 2024-09-07: wsfulton
             #2875 Fix swig-4.1.0 regression using the %interface family of macros
             for multiple inheritance and common bases.

Examples/test-suite/cpp11_strongly_typed_enumerations.i

@@ -263,3 +263,14 @@ private:
     Val2 = 1172,
   };
 %}
+
+// Test handling of %rename of enum class and an enumerator.
+%rename(Enum18) QEnum18;
+%rename(Val1) QVal1;
+%inline %{
+  enum class QEnum18
+  {
+    QVal1 = 1181,
+    Val2 = 1182,
+  };
+%}

Examples/test-suite/cpp11_strongly_typed_enumerations_perl_const.i

@@ -0,0 +1,3 @@
+%module cpp11_strongly_typed_enumerations_perl_const
+
+%include "cpp11_strongly_typed_enumerations.i"

Examples/test-suite/perl5/Makefile.in

@@ -23,6 +23,9 @@ CPP_TEST_CASES += \
 	memberin1 \
 	director_nestedmodule \
 
+CPP11_TEST_CASES += \
+	cpp11_strongly_typed_enumerations_perl_const
+
 C_TEST_CASES += \
 	li_cstring \
 	li_cdata_carrays \
@@ -34,7 +37,7 @@ include $(srcdir)/../common.mk
 # none!
 
 # Custom tests - tests with additional commandline options
-# none!
+cpp11_strongly_typed_enumerations_perl_const.cpptest: SWIGOPT += -const
 
 # Rules for the different types of tests
 %.cpptest:

Examples/test-suite/perl5/cpp11_strongly_typed_enumerations_perl_const_runme.pl

@@ -0,0 +1,8 @@
+use strict;
+use warnings;
+use Test::More tests => 4;
+BEGIN { use_ok('cpp11_strongly_typed_enumerations_perl_const') }
+require_ok('cpp11_strongly_typed_enumerations_perl_const');
+
+is(cpp11_strongly_typed_enumerations_perl_const::Enum18::Val1, 1181);
+is(cpp11_strongly_typed_enumerations_perl_const::Enum18::Val2, 1182);

Examples/test-suite/perl5/cpp11_strongly_typed_enumerations_runme.pl

@@ -1,6 +1,6 @@
 use strict;
 use warnings;
-use Test::More tests => 78;
+use Test::More tests => 80;
 BEGIN { use_ok('cpp11_strongly_typed_enumerations') }
 require_ok('cpp11_strongly_typed_enumerations');
 
@@ -166,3 +166,5 @@ enumCheck(cpp11_strongly_typed_enumerations::globalTest1($cpp11_strongly_typed_e
 enumCheck(cpp11_strongly_typed_enumerations::globalTest2($cpp11_strongly_typed_enumerations::Class1::Enum12_Val5c), 1121);
 #enumCheck(cpp11_strongly_typed_enumerations::globalTest3($cpp11_strongly_typed_enumerations::Class1::Struct1::Enum12_Val5f), 3121);
 
+$val = enumCheck($cpp11_strongly_typed_enumerations::Enum18_Val1, 1181);
+$val = enumCheck($cpp11_strongly_typed_enumerations::Enum18_Val2, 1182);

Source/Modules/perl5.cxx

@@ -107,7 +107,7 @@ static String *pcode = 0;	/* Perl code associated with each class */
 static int member_func = 0;	/* Set to 1 when wrapping a member function */
 static String *func_stubs = 0;	/* Function stubs */
 static String *const_stubs = 0;	/* Constant stubs */
-static int num_consts = 0;	/* Number of constants */
+static Node *const_stubs_enum_class = 0; /* Node for enum class if we're currently generating one */
 static String *var_stubs = 0;	/* Variable stubs */
 static String *exported = 0;	/* Exported symbols */
 static String *pragma_include = 0;
@@ -585,10 +585,9 @@ public:
       /* Emit package code for different classes */
       Printf(f_pm, "%s", pm);
 
-      if (num_consts > 0) {
+      if (Len(const_stubs) > 0) {
 	/* Emit constant stubs */
 	Printf(f_pm, "\n# ------- CONSTANT STUBS -------\n\n");
-	Printf(f_pm, "package %s;\n\n", namespace_module);
 	Printf(f_pm, "%s", const_stubs);
       }
 
@@ -1120,8 +1119,22 @@ public:
 	       "tie %__", iname, "_hash,\"", is_shadow(type), "\", $",
 	       cmodule, "::", iname, ";\n", "$", iname, "= \\%__", iname, "_hash;\n", "bless $", iname, ", ", is_shadow(type), ";\n", NIL);
       } else if (do_constants) {
-	Printv(const_stubs, "sub ", name, " () { $", cmodule, "::", name, " }\n", NIL);
+	char *dcolon = Strstr(name, "::");
-	num_consts++;
+	if (!dcolon) {
+	  if (Len(const_stubs) == 0 || const_stubs_enum_class != NULL) {
+	    Printf(const_stubs, "package %s;\n", namespace_module);
+	    const_stubs_enum_class = NULL;
+	  }
+	  Printv(const_stubs, "sub ", iname, " () { $", cmodule, "::", iname, " }\n", NIL);
+	} else {
+	  // C++11 strongly-typed enum.
+	  Node *parent = Getattr(n, "parentNode");
+	  if (const_stubs_enum_class != parent) {
+	    Printf(const_stubs, "package %s::%s;\n", namespace_module, Getattr(parent, "sym:name"));
+	    const_stubs_enum_class = parent;
+	  }
+	  Printv(const_stubs, "sub ", Getattr(n, "enumvalueDeclaration:sym:name"), " () { $", cmodule, "::", iname, " }\n", NIL);
+	}
       } else {
 	Printv(var_stubs, "*", iname, " = *", cmodule, "::", iname, ";\n", NIL);
       }