Fix incorrectly shown warning for empty template instantiation used as a base class.

CHANGES.current

@@ -12,6 +12,14 @@ Version 4.0.0 (in progress)
 	    after template<T>).  Fixes https://github.com/swig/swig/issues/1031
 	    reported by Artem V L.
 
+2017-08-02: wsfulton
+            Fix incorrectly shown warning when an empty template instantiation was used on a
+            class used as a base class and that base class was explicitly ignored with %ignore.
+            Example of the warning which will no longer appear:
+
+              Warning 401: Base class 'Functor< int,int >' has no name as it is an empty
+              template instantiated with '%template()'. Ignored.
+
 2017-07-17: fflexo
             [Java] #674 Add std_list.i to add support for std::list containers. The Java proxy
             extends java.util.AbstractSequentialList and makes the C++ std::list container look

Examples/test-suite/common.mk

@@ -418,6 +418,7 @@ CPP_TEST_CASES += \
 	template_default_inherit \
 	template_default_qualify \
 	template_default_vw \
+	template_empty_inherit \
 	template_enum \
 	template_enum_ns_inherit \
 	template_enum_typedef \

Examples/test-suite/template_empty_inherit.i

@@ -0,0 +1,30 @@
+%module template_empty_inherit
+
+%inline %{
+template<class Arg, typename Result> struct Functor {
+  virtual Result operator()(Arg x) const = 0;
+};
+%}
+
+// Bug fix - %ignore was resulting in this warning:
+// Warning 401: Base class 'Functor< int,int >' has no name as it is an empty template instantiated with '%template()'. Ignored.
+%ignore Functor<int, int>;
+%template() Functor<int, int>;
+
+%inline %{
+#include <algorithm>
+struct SquareFunctor : Functor<int, int> {
+  int operator()(int v) const { return v*v; }
+};
+%}
+
+%include <std_vector.i>
+%template(VectorInt) std::vector<int>;
+
+%inline %{
+std::vector<int> squares(const std::vector<int>& vi) {
+  std::vector<int> result;
+  std::transform(vi.begin(), vi.end(), std::back_inserter(result), SquareFunctor());
+  return result;
+}
+%}

Source/Modules/typepass.cxx

@@ -187,10 +187,12 @@ class TypePass:private Dispatcher {
 			ilist = alist = NewList();
 		      Append(ilist, bcls);
 		    } else {
+		      if (!GetFlag(bcls, "feature:ignore")) {
 			Swig_warning(WARN_TYPE_UNDEFINED_CLASS, Getfile(bname), Getline(bname), "Base class '%s' has no name as it is an empty template instantiated with '%%template()'. Ignored.\n", SwigType_namestr(bname));
 			Swig_warning(WARN_TYPE_UNDEFINED_CLASS, Getfile(bcls), Getline(bcls), "The %%template directive must be written before '%s' is used as a base class and be declared with a name.\n", SwigType_namestr(bname));
 		      }
 		    }
+		  }
 		  break;
 		}
 		if (Strcmp(nodeType(bcls), "classforward") != 0) {
@@ -209,9 +211,11 @@ class TypePass:private Dispatcher {
 		      ilist = alist = NewList();
 		    Append(ilist, bcls);
 		  } else {
+		    if (!GetFlag(bcls, "feature:ignore")) {
 		      Swig_warning(WARN_TYPE_UNDEFINED_CLASS, Getfile(bname), Getline(bname), "Base class '%s' has no name as it is an empty template instantiated with '%%template()'. Ignored.\n", SwigType_namestr(bname));
 		      Swig_warning(WARN_TYPE_UNDEFINED_CLASS, Getfile(bcls), Getline(bcls), "The %%template directive must be written before '%s' is used as a base class and be declared with a name.\n", SwigType_namestr(bname));
 		    }
+		  }
 		} else {
 		  Swig_warning(WARN_TYPE_UNDEFINED_CLASS, Getfile(bname), Getline(bname), "Base class '%s' undefined.\n", SwigType_namestr(bname));
 		  Swig_warning(WARN_TYPE_UNDEFINED_CLASS, Getfile(bcls), Getline(bcls), "'%s' must be defined before it is used as a base class.\n", SwigType_namestr(bname));