Ensure that param-array matching works correctly (pythonnet#1304)

filmor · web-flow · commit 4133927e5e8a · 2020-12-10T18:47:00.000+01:00
We can match n Python parameters to exactly n+1 C# parameters of which the last one is a param-array. Fixes pythonnet#1302. There are still two cases that are not covered.
diff --git a/src/runtime/methodbinder.cs b/src/runtime/methodbinder.cs
@@ -512,7 +512,7 @@ static object[] TryConvertArguments(ParameterInfo[] pi, bool paramsArray,
                 {
                     if(arrayStart == paramIndex)
                     {
-                        op = HandleParamsArray(args, arrayStart, pyArgCount, out isNewReference);                                                                 
+                        op = HandleParamsArray(args, arrayStart, pyArgCount, out isNewReference);
                     }
                     else
                     {
@@ -652,7 +652,7 @@ static bool MatchesArgumentCount(int positionalArgumentCount, ParameterInfo[] pa
             {
                 match = true;
             }
-            else if (positionalArgumentCount < parameters.Length)
+            else if (positionalArgumentCount < parameters.Length && (!paramsArray || positionalArgumentCount == parameters.Length - 1))
             {
                 // every parameter past 'positionalArgumentCount' must have either
                 // a corresponding keyword argument or a default parameter
@@ -677,7 +677,7 @@ static bool MatchesArgumentCount(int positionalArgumentCount, ParameterInfo[] pa
                         defaultArgList.Add(parameters[v].GetDefaultValue());
                         defaultsNeeded++;
                     }
-                    else if(!paramsArray)
+                    else if (!paramsArray)
                     {
                         match = false;
                     }
diff --git a/src/testing/constructortests.cs b/src/testing/constructortests.cs
@@ -48,4 +48,22 @@ public SubclassConstructorTest(Exception v)
             value = v;
         }
     }
+
+    public class MultipleConstructorsTest
+    {
+        public string value;
+        public Type[] type;
+
+        public MultipleConstructorsTest()
+        {
+            value = "";
+            type = new Type[1] { null };
+        }
+
+        public MultipleConstructorsTest(string s, params Type[] tp)
+        {
+            value = s;
+            type = tp;
+        }
+    }
 }
diff --git a/src/testing/methodtest.cs b/src/testing/methodtest.cs
@@ -703,6 +703,16 @@ public static string DefaultParamsWithOverloading(int a = 5, int b = 6, int c =
         {
             return $"{a}{b}{c}{d}XXX";
         }
+
+        public static string ParamsArrayOverloaded(int i = 1)
+        {
+            return "without params-array";
+        }
+
+        public static string ParamsArrayOverloaded(int i, params int[] paramsArray)
+        {
+            return "with params-array";
+        }
     }
 
 
diff --git a/src/tests/test_constructors.py b/src/tests/test_constructors.py
@@ -44,3 +44,12 @@ class Sub(System.Exception):
     instance = Sub()
     ob = SubclassConstructorTest(instance)
     assert isinstance(ob.value, System.Exception)
+
+
+def test_multiple_constructor():
+    from Python.Test import MultipleConstructorsTest
+    import System
+
+    # Test parameterless
+    ob = MultipleConstructorsTest()
+    assert ob.value == ""
diff --git a/src/tests/test_method.py b/src/tests/test_method.py
@@ -1188,3 +1188,36 @@ def test_keyword_arg_method_resolution():
     ob = MethodArityTest()
     assert ob.Foo(1, b=2) == "Arity 2"
 
+def test_params_array_overload():
+    res = MethodTest.ParamsArrayOverloaded()
+    assert res == "without params-array"
+
+    res = MethodTest.ParamsArrayOverloaded(1)
+    assert res == "without params-array"
+
+    res = MethodTest.ParamsArrayOverloaded(i=1)
+    assert res == "without params-array"
+
+    res = MethodTest.ParamsArrayOverloaded(1, 2)
+    assert res == "with params-array"
+
+    res = MethodTest.ParamsArrayOverloaded(1, 2, 3)
+    assert res == "with params-array"
+
+    res = MethodTest.ParamsArrayOverloaded(1, paramsArray=[])
+    assert res == "with params-array"
+
+    res = MethodTest.ParamsArrayOverloaded(1, i=1)
+    assert res == "with params-array"
+
+    res = MethodTest.ParamsArrayOverloaded(1, 2, 3, i=1)
+    assert res == "with params-array"
+
+    # These two cases are still incorrectly failing:
+
+    # res = MethodTest.ParamsArrayOverloaded(1, 2, i=1)
+    # assert res == "with params-array"
+
+    # res = MethodTest.ParamsArrayOverloaded(paramsArray=[], i=1)
+    # assert res == "with params-array"
+

Original file line number	Diff line number	Diff line change
`@@ -512,7 +512,7 @@ static object[] TryConvertArguments(ParameterInfo[] pi, bool paramsArray,`
`512`	`512`	`{`
`513`	`513`	`if(arrayStart == paramIndex)`
`514`	`514`	`{`
`515`		`- op = HandleParamsArray(args, arrayStart, pyArgCount, out isNewReference);`
	`515`	`+ op = HandleParamsArray(args, arrayStart, pyArgCount, out isNewReference);`
`516`	`516`	`}`
`517`	`517`	`else`
`518`	`518`	`{`
`@@ -652,7 +652,7 @@ static bool MatchesArgumentCount(int positionalArgumentCount, ParameterInfo[] pa`
`652`	`652`	`{`
`653`	`653`	`match = true;`
`654`	`654`	`}`
`655`		`- else if (positionalArgumentCount < parameters.Length)`
	`655`	`+ else if (positionalArgumentCount < parameters.Length && (!paramsArray \|\| positionalArgumentCount == parameters.Length - 1))`
`656`	`656`	`{`
`657`	`657`	`// every parameter past 'positionalArgumentCount' must have either`
`658`	`658`	`// a corresponding keyword argument or a default parameter`
`@@ -677,7 +677,7 @@ static bool MatchesArgumentCount(int positionalArgumentCount, ParameterInfo[] pa`
`677`	`677`	`defaultArgList.Add(parameters[v].GetDefaultValue());`
`678`	`678`	`defaultsNeeded++;`
`679`	`679`	`}`
`680`		`- else if(!paramsArray)`
	`680`	`+ else if (!paramsArray)`
`681`	`681`	`{`
`682`	`682`	`match = false;`
`683`	`683`	`}`
Original file line number	Diff line number	Diff line change
`@@ -703,6 +703,16 @@ public static string DefaultParamsWithOverloading(int a = 5, int b = 6, int c =`
`703`	`703`	`{`
`704`	`704`	`return $"{a}{b}{c}{d}XXX";`
`705`	`705`	`}`
	`706`	`+`
	`707`	`+ public static string ParamsArrayOverloaded(int i = 1)`
	`708`	`+ {`
	`709`	`+ return "without params-array";`
	`710`	`+ }`
	`711`	`+`
	`712`	`+ public static string ParamsArrayOverloaded(int i, params int[] paramsArray)`
	`713`	`+ {`
	`714`	`+ return "with params-array";`
	`715`	`+ }`
`706`	`716`	`}`
`707`	`717`
`708`	`718`