Consistency in warnings for ambiguous/redefined templated constructors

Constructors used to warn with:
  Warning 302: Identifier 'Json' redefined (ignored)
But now warn with:
  Warning 322: Redundant redeclaration of 'Json'

Note that 320 is a warning that is shown by default and 322 is a
hidden warning by default.

The warning is now consistent for both templated methods and constructors
that are deemed redefined. See cpp11_template_parameters_decltype
testcase. This testcase has been enhanced with a runtime test to check
that the workarounds for overloaded templated constructors/methods do
work.

Examples/test-suite/cpp11_template_parameters_decltype.i

@@ -1,9 +1,5 @@
 %module cpp11_template_parameters_decltype
 
-%include <std_string.i>
-%include <std_vector.i>
-%include <std_pair.i>
-
 %inline %{
 // Github issue #1589
 template <decltype(true) X = true>
@@ -13,33 +9,99 @@ void A() { }
 // %template(A) A<>; // not working
 %template(A) A<true>; // workaround
 
+
+%include <std_string.i>
+%include <std_vector.i>
+%include <std_map.i>
+
 #pragma SWIG nowarn=SWIGWARN_CPP11_DECLTYPE
 
-// Non-template expression equivalent to template expression further down:
-%inline %{
-#include <utility>
-#include <vector>
-  void f(bool c = std::is_constructible<std::string, decltype(std::declval<std::vector<std::pair<int, int>>>().begin()->first)>::value) {}
+%{
+// Simple implementation of helper functions required in test below
+std::string array(std::vector<std::string>::const_iterator begin, std::vector<std::string>::const_iterator end) {
+  return "not implemented";
+}
+std::string object(std::map<std::string, std::string>::const_iterator begin, std::map<std::string, std::string>::const_iterator end) {
+  return "not implemented";
+}
 %}
 
 %inline %{
+#include <iostream>
+
 // Github issue #1590
 struct Converter {
   std::string to_json() const { return std::string(); }
 };
 struct Json {
-  Json(std::string s) {}
+  int ctor;
+  Json(std::string s) : ctor(0) {}
   template < class T, class = decltype(&T::to_json) >
-    Json(const T & t) : Json(t.to_json()) {}
+    Json(const T & t) : Json(t.to_json()) { ctor = 1; }
 
 // Github issue #1589
   // Implicit constructor: map-like objects (std::map, std::unordered_map, etc)
   template <class M, typename std::enable_if<
       std::is_constructible<std::string, decltype(std::declval<M>().begin()->first)>::value,
       int>::type = 0>
-          Json(const M & m) : Json(object(m.begin(), m.end())) {}
+          Json(const M & m) : Json(object(m.begin(), m.end())) { ctor = 2; }
+  // Implicit constructor: vector-like objects (std::list, std::vector, std::set, etc)
+  template <class V, typename std::enable_if<
+      std::is_constructible<Json, decltype(*std::declval<V>().begin())>::value,
+          int>::type = 0>
+  Json(const V & v) : Json(array(v.begin(), v.end())) { ctor = 3; }
+
+  // Same sort of thing as constructors above but for a member function
+  int mmm(std::string s) { return 100; }
+  template < class T, class = decltype(&T::to_json) >
+    int mmm(const T & t) { return 101; }
+  template <class M, typename std::enable_if<
+    std::is_constructible<std::string, decltype(std::declval<M>().begin()->first)>::value,
+    int>::type = 0>
+      int mmm(const M & m) { return 102; }
+  template <class V, typename std::enable_if<
+    std::is_constructible<Json, decltype(*std::declval<V>().begin())>::value,
+    int>::type = 0>
+      int mmm(const V & v) { return 103; }
 };
+
+void tester(bool show) {
+  // Example usage from c++
+  if (show) {
+    Json json0(std::string("hi"));
+    Converter converter;
+    std::cout << "json0 " << json0.ctor << std::endl;
+    Json json1 = Json(converter);
+    std::cout << "json1 " << json1.ctor << std::endl;
+    std::map<std::string, std::string> myStringStringMap;
+    Json json2 = Json(myStringStringMap);
+    std::cout << "json2 " << json2.ctor << std::endl;
+    std::vector<std::string> myVectorString;
+    Json json3 = Json(myVectorString);
+    std::cout << "json3 " << json3.ctor << std::endl;
+
+    std::cout << "json0.mmm " << json0.mmm("bye") << std::endl;
+    std::cout << "json1.mmm " << json1.mmm(converter) << std::endl;
+    std::cout << "json2.mmm " << json2.mmm(myStringStringMap) << std::endl;
+    std::cout << "json3.mmm " << json3.mmm(myVectorString) << std::endl;
+  }
+}
 %}
 
+%template(VectorString) std::vector<std::string>;
+%template(MapStringString) std::map<std::string, std::string>;
+
+// There is quite a bit of inconsistency about providing or not providing default
+// template parameters that needs investigating. Below is a combination that works.
+
+// Note that instantiating the two Json constructors (or the two mmm methods) that
+// use enable_if is ambiguous given the enable_if is not evaluated by SWIG.
+
 // %template(Json) Json::Json<Converter>; // not working
 %template(Json) Json::Json<Converter, std::string>; // workaround
+%template(Json) Json::Json<std::map<std::string, std::string>, 0>;
+%template(Json) Json::Json<std::vector<std::string>, 0>;
+
+%template(mmm) Json::mmm<Converter, std::string>;
+%template(mmm) Json::mmm<std::map<std::string, std::string>, 0>;
+%template(mmm) Json::mmm<std::vector<std::string>, 0>;

Examples/test-suite/java/cpp11_template_parameters_decltype_runme.java

@@ -0,0 +1,45 @@
+import cpp11_template_parameters_decltype.*;
+
+public class cpp11_template_parameters_decltype_runme {
+
+  static {
+    try {
+	System.loadLibrary("cpp11_template_parameters_decltype");
+    } 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[]) {
+    boolean show = false; // for debugging
+
+    cpp11_template_parameters_decltype.tester(show);
+    Json json0 = new Json("hi");
+    if (json0.getCtor() != 0)
+      throw new RuntimeException("json0 failed");
+    if (json0.mmm("bye") != 100)
+      throw new RuntimeException("json0.mmm failed");
+
+    Converter converter = new Converter();
+    Json json1 = new Json(converter);
+    if (json1.getCtor() != 1)
+      throw new RuntimeException("json1 failed");
+    if (json1.mmm(converter) != 101)
+      throw new RuntimeException("json1.mmm failed");
+
+    MapStringString myMapStringString = new MapStringString();
+    Json json2 = new Json(myMapStringString);
+    if (json2.getCtor() != 2)
+      throw new RuntimeException("json2 failed");
+    if (json2.mmm(myMapStringString) != 102)
+      throw new RuntimeException("json2.mmm failed");
+
+    VectorString myVectorString = new VectorString();
+    Json json3 = new Json(myVectorString);
+    if (json3.getCtor() != 3)
+      throw new RuntimeException("json3 failed");
+    if (json3.mmm(myVectorString) != 103)
+      throw new RuntimeException("json3.mmm failed");
+  }
+}

Source/Swig/naming.c

@@ -972,8 +972,8 @@ static int nodes_are_equivalent(Node *a, Node *b, int a_inclass) {
     }
   }
 
-  if (Cmp(ta, "cdecl") == 0) {
-    /* both cdecl case */
+  if (Equal(ta, "cdecl") || Equal(ta, "constructor")) {
+    /* both cdecl or constructor case */
     /* typedef */
     String *a_storage = Getattr(a, "storage");
     String *b_storage = Getattr(b, "storage");