Fix C enum forward declarations in some target languages (notably Java)

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@13030 626c5289-ae23-0410-ae9c-e8d60b6d4f22

CHANGES.current

@@ -5,3 +5,6 @@ See the RELEASENOTES file for a summary of changes in each release.
 Version 2.0.7 (in progress)
 ===========================
 
+2012-05-01: wsfulton
+            Fix generated code for C forward enum declarations in some languages.
+

Examples/test-suite/common.mk

@@ -495,6 +495,7 @@ C_TEST_CASES += \
 	constant_expr \
 	empty \
 	enums \
+	enum_forward \
 	extern_declaration \
 	funcptr \
 	function_typedef \

Examples/test-suite/csharp/enum_forward_runme.cs

@@ -0,0 +1,16 @@
+using System;
+using enum_forwardNamespace;
+
+public class runme {
+  static void Main() {
+    ForwardEnum1 f1 = enum_forward.get_enum1();
+    f1 = enum_forward.test_function1(f1);
+
+    ForwardEnum2 f2 = enum_forward.get_enum2();
+    f2 = enum_forward.test_function2(f2);
+
+    ForwardEnum3 f3 = enum_forward.get_enum3();
+    f3 = enum_forward.test_function3(f3);
+  }
+}
+

Examples/test-suite/enum_forward.i

@@ -0,0 +1,35 @@
+%module enum_forward
+
+%{
+enum ForwardEnum1 { AAA, BBB };
+enum ForwardEnum2 { CCC, DDD };
+%}
+
+%inline %{
+enum ForwardEnum1;
+enum ForwardEnum1 get_enum1() { return AAA; }
+enum ForwardEnum1 test_function1(enum ForwardEnum1 e) {
+  return e;
+}
+%}
+
+%inline %{
+enum ForwardEnum2;
+enum ForwardEnum2;
+enum ForwardEnum2 get_enum2() { return CCC; }
+enum ForwardEnum2 test_function2(enum ForwardEnum2 e) {
+  return e;
+}
+enum ForwardEnum2;
+%}
+
+%inline %{
+enum ForwardEnum3;
+enum ForwardEnum3 { EEE, FFF };
+enum ForwardEnum3 get_enum3() { return EEE; }
+enum ForwardEnum3 test_function3(enum ForwardEnum3 e) {
+  return e;
+}
+enum ForwardEnum3;
+%}
+

Examples/test-suite/java/enum_forward_runme.java

@@ -0,0 +1,33 @@
+
+import enum_forward.*;
+
+public class enum_forward_runme {
+
+  static {
+    try {
+        System.loadLibrary("enum_forward");
+    } catch (UnsatisfiedLinkError e) {
+      System.err.println("Native code library failed to load. See the chapter on Dynamic Linking Problems in the SWIG Java documentation for help.\n" + e);
+      System.exit(1);
+    }
+  }
+
+  public static void main(String argv[]) 
+  {
+    try {
+      ForwardEnum1 f1 = enum_forward.get_enum1();
+      f1 = enum_forward.test_function1(f1);
+    } catch (IllegalArgumentException e) {
+    }
+
+    try {
+      ForwardEnum2 f2 = enum_forward.get_enum2();
+      f2 = enum_forward.test_function2(f2);
+    } catch (IllegalArgumentException e) {
+    }
+
+    ForwardEnum3 f3 = enum_forward.get_enum3();
+    f3 = enum_forward.test_function3(f3);
+  }
+}
+

Examples/test-suite/python/enum_forward_runme.py

@@ -0,0 +1,10 @@
+import enum_forward
+  
+f1 = enum_forward.get_enum1();
+f1 = enum_forward.test_function1(f1);
+
+f2 = enum_forward.get_enum2();
+f2 = enum_forward.test_function2(f2);
+
+f3 = enum_forward.get_enum3();
+f3 = enum_forward.test_function3(f3);

Source/Modules/lang.cxx

@@ -1664,6 +1664,8 @@ int Language::enumvalueDeclaration(Node *n) {
 
 int Language::enumforwardDeclaration(Node *n) {
   (void) n;
+  if (GetFlag(n, "enumMissing"))
+    enumDeclaration(n); // Generate an empty enum in target language
   return SWIG_OK;
 }
 
@@ -3156,7 +3158,9 @@ Node *Language::enumLookup(SwigType *s) {
       n = Swig_symbol_clookup(base, stab);
       if (!n)
 	break;
-      if (Strcmp(nodeType(n), "enum") == 0)
+      if (Equal(nodeType(n), "enum"))
+	break;
+      if (Equal(nodeType(n), "enumforward") && GetFlag(n, "enumMissing"))
 	break;
       n = parentNode(n);
       if (!n)

Source/Modules/typepass.cxx

@@ -886,7 +886,22 @@ class TypePass:private Dispatcher {
 
     // Use enumDeclaration() to do all the hard work.
     // Note that no children can be emitted in a forward declaration as there aren't any.
-    return enumDeclaration(n);
+    int result = enumDeclaration(n);
+    if (result == SWIG_OK) {
+      // Detect when the real enum matching the forward enum declaration has not been parsed/declared
+      SwigType *ty = SwigType_typedef_resolve_all(Getattr(n, "type"));
+      Replaceall(ty, "enum ", "");
+      Node *nn = Swig_symbol_clookup(ty, 0);
+
+      String *nodetype = nn ? nodeType(nn) : 0;
+      if (nodetype) {
+	if (Equal(nodetype, "enumforward")) {
+	  SetFlag(nn, "enumMissing");
+	} // if a real enum was declared this would be an "enum" node type
+      }
+      Delete(ty);
+    }
+    return result;
   }
 
 #ifdef DEBUG_OVERLOADED