template template parameters patch tidyup

- Document change in CHANGES file
- Minor tweaks and whitespace fixes in stype.c
- Enhance testcase
- Synchronise Java and Python runt test in testcase

5 files changed, 61 insertions, 33 deletions

diff --git a/CHANGES.current b/CHANGES.current
index 473db0696..b97d7709d 100644
--- a/CHANGES.current
+++ b/CHANGES.current
@@ -7,6 +7,9 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.1.0 (in progress)
 ===========================
 
+2021-03-22: goto40
+            #1977 Fix handling of template template parameters.
+
 2021-03-21: olly
 	    #1929, #1978 [PHP] Add support for PHP 8.
 
diff --git a/Examples/test-suite/java/template_template_parameters_runme.java b/Examples/test-suite/java/template_template_parameters_runme.java
index 6ccc858ac..613f9087c 100644
--- a/Examples/test-suite/java/template_template_parameters_runme.java
+++ b/Examples/test-suite/java/template_template_parameters_runme.java
@@ -29,12 +29,17 @@ public class template_template_parameters_runme {
 
     // Test second part
     FloatTestStruct floatTestStruct = new FloatTestStruct();
-    FloatContainer2 floatContainer2 = floatTestStruct.getX(); 
+    FloatContainer2 floatContainer2 = floatTestStruct.getX();
     floatContainer2.setX(8.1f);
     IntTestStruct intTestStruct = new IntTestStruct();
-    IntContainer1 intContainer1 = intTestStruct.getX(); 
+    IntContainer1 intContainer1 = intTestStruct.getX();
     intContainer1.setX(91);
-    if (intContainer1.getX()!=91) 
+    if (intContainer1.getX() != 91)
+      throw new RuntimeException("Failed");
+    if (intTestStruct.getX().getX() != 91)
+      throw new RuntimeException("Failed");
+    IntTestStruct intTestStructReturned = template_template_parameters.TestStructContainer1Method(intTestStruct);
+    if (intTestStructReturned.getX().getX() != 101)
       throw new RuntimeException("Failed");
   }
 }
diff --git a/Examples/test-suite/python/template_template_parameters_runme.py b/Examples/test-suite/python/template_template_parameters_runme.py
index 4c018176e..4b0e27d9c 100644
--- a/Examples/test-suite/python/template_template_parameters_runme.py
+++ b/Examples/test-suite/python/template_template_parameters_runme.py
@@ -1,5 +1,18 @@
 from template_template_parameters import *
 
+# Test first part
+listBool = ListFastBool()
+listBool.item = True
+x_boolean = listBool.allotype
+if listBool.item != True:
+  raise RuntimeError("Failed")
+
+listDouble = ListDefaultDouble()
+listDouble.item = 10.2
+x_double = listDouble.allotype
+if listDouble.item != 10.2:
+  raise RuntimeError("Failed")
+
 # Test second part
 floatTestStruct = FloatTestStruct()
 floatContainer2 = floatTestStruct.x
@@ -7,8 +20,11 @@ floatContainer2.x = 8.1
 intTestStruct = IntTestStruct()
 intContainer1 = intTestStruct.x
 intContainer1.x = 91
-if intContainer1.x!=91:
-    raise RuntimeError("Failed")
-if intTestStruct.x.x!=91:
-    raise RuntimeError("Failed")
+if intContainer1.x != 91:
+  raise RuntimeError("Failed")
+if intTestStruct.x.x != 91:
+  raise RuntimeError("Failed")
+intTestStructReturned = TestStructContainer1Method(intTestStruct)
+if intTestStructReturned.x.x != 101:
+  raise RuntimeError("Failed")
 
diff --git a/Examples/test-suite/template_template_parameters.i b/Examples/test-suite/template_template_parameters.i
index 3d8825697..53b18b0b0 100644
--- a/Examples/test-suite/template_template_parameters.i
+++ b/Examples/test-suite/template_template_parameters.i
@@ -48,6 +48,11 @@ struct TestStruct {
     TemplateTemplateT<BaseT> x;
 };
 
+TestStruct<int, Container1> TestStructContainer1Method(TestStruct<int, Container1> ts1) {
+  ts1.x.x += 10;
+  return ts1;
+}
+
 %}
 
 /* part 1 */
@@ -61,8 +66,8 @@ struct TestStruct {
 %template(DoubleAllocFast) pfc::alloc_fast<double>;
 
 /* part 2 */
-%template(IntTestStruct) TestStruct<int, Container1>;
-%template(FloatTestStruct) TestStruct<float, Container2>;
 %template(IntContainer1) Container1<int>;
 %template(FloatContainer2) Container2<float>;
+%template(IntTestStruct) TestStruct<int, Container1>;
+%template(FloatTestStruct) TestStruct<float, Container2>;
 
diff --git a/Source/Swig/stype.c b/Source/Swig/stype.c
index 1c7f6cc00..5f876ff04 100644
--- a/Source/Swig/stype.c
+++ b/Source/Swig/stype.c
@@ -1290,30 +1290,29 @@ void SwigType_typename_replace(SwigType *t, String *pat, String *rep) {
 	/* Replaces a type of the form 'pat' with 'rep<args>' */
 	Replace(e, pat, rep, DOH_REPLACE_ANY);
       } else if (SwigType_istemplate(e)) {
-    /* Replaces a type of the form 'pat<args>' with 'rep' */
-    {
-       /* To match "e=TemplateTemplateT<(float)>"
-       * with "pat=TemplateTemplateT"
-       * we need to compare only the first part of the string e.
-       */
-      int len = DohLen(pat);
-
-      /* DohLen(e) > len, not >= (because we expecte at least a
-       * character '<' following the template typename)
-       */
-      if (DohLen(e)>len) {
-        String *firstPartOfType = NewStringWithSize(e, len);
-        const char* e_as_char = DohData(e);
-
-        if (Equal(firstPartOfType, pat) && e_as_char[len]=='<') {
-          String *repbase = SwigType_templateprefix(rep);
-          Replace(e, pat, repbase, DOH_REPLACE_ID | DOH_REPLACE_FIRST);
-          Delete(repbase);
-        }
-        Delete(firstPartOfType);
-  
-      }
-    }
+	/* Replaces a type of the form 'pat<args>' with 'rep' */
+	{
+	  /* To match "e=TemplateTemplateT<(float)>"
+	   * with "pat=TemplateTemplateT"
+	   * we need to compare only the first part of the string e.
+	   */
+	  int len = Len(pat);
+
+	  /* Len(e) > len, not >= (because we expect at least a
+	   * character '<' following the template typename)
+	   */
+	  if (Len(e) > len) {
+	    String *firstPartOfType = NewStringWithSize(e, len);
+	    const char* e_as_char = Char(e);
+
+	    if (Equal(firstPartOfType, pat) && e_as_char[len] == '<') {
+	      String *repbase = SwigType_templateprefix(rep);
+	      Replace(e, pat, repbase, DOH_REPLACE_ID | DOH_REPLACE_FIRST);
+	      Delete(repbase);
+	    }
+	    Delete(firstPartOfType);
+	  }
+	}
 
 	{
 	  String *tsuffix;