Add Javascript (JSC) support for type conversion

Fix types_directive testcase to ensure the %types code is actually
called and not just cast from one type to the other.

Examples/test-suite/types_directive.i

@@ -19,10 +19,11 @@ struct Date {
 };
 
 struct Time1 {
-  Time1(unsigned int year, unsigned int month, unsigned int day, unsigned int seconds) : date(year, month, day), seconds(seconds) {}
+  Time1(unsigned int year, unsigned int month, unsigned int day, unsigned int seconds) : padding(), date(year, month, day), seconds(seconds) {}
   Date &dateFromTime() {
     return date;
   }
+  unsigned int padding; // so that memory layout is not the same as Date
   Date date;
   unsigned int seconds;
 };

Lib/javascript/jsc/javascriptrun.swg

@@ -117,27 +117,25 @@ SWIGRUNTIME int SWIG_JSC_ConvertInstancePtr(JSContextRef context, JSObjectRef ob
   SwigPrivData *cdata;
 
   cdata = (SwigPrivData *) JSObjectGetPrivate(objRef);
-  if(cdata == NULL) {
+  if (cdata == NULL) {
     return SWIG_ERROR;
   }
-  if(cdata->info != info) {
-    bool type_valid = false;
-    swig_cast_info *t = info->cast;
-    while(t != NULL) {
-      if(t->type == cdata->info) {
-        type_valid = true;
-        break;
-      }
-      t = t->next;
-    }
-    if(!type_valid) {
-      return SWIG_TypeError;
+  assert(ptr);
+  *ptr = NULL;
+  if (cdata->info == info) {
+    *ptr = cdata->swigCObject;
+  } else {
+    swig_cast_info *tc = SWIG_TypeCheckStruct(cdata->info, info);
+    if (tc) {
+      int newmemory = 0;
+      *ptr = SWIG_TypeCast(tc, cdata->swigCObject, &newmemory);
+      assert(!newmemory); /* newmemory handling not yet implemented */
+    } else {
+      return SWIG_ERROR;
     }
   }
 
-  *ptr = cdata->swigCObject;
-
-  if(flags & SWIG_POINTER_DISOWN) {
+  if (flags & SWIG_POINTER_DISOWN) {
     cdata->swigCMemOwn = false;
   }
 

Lib/javascript/jsc/javascriptruntime.swg

@@ -11,6 +11,7 @@
 #include <string.h>
 #include <errno.h>
 #include <limits.h>
+#include <assert.h>
 %}
 
 %insert(runtime) "swigrun.swg";         /* SWIG API */