From 6df753f4445d854521d1e647bf961a565e13c958 Mon Sep 17 00:00:00 2001
From: Victor Milovanov <lost@losttech.software>
Date: Sat, 29 Aug 2020 15:06:11 -0700
Subject: [PATCH] fix `object[]` parameters taking precedence when should not
 in overload resolution

---
 CHANGELOG.md                |  6 ++++++
 src/runtime/methodbinder.cs | 20 ++++++++++----------
 src/testing/methodtest.cs   |  3 ++-
 src/tests/test_method.py    |  9 ++++++---
 4 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 51e4f842e..f7cf0859b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,12 @@ project adheres to [Semantic Versioning][].
 
 This document follows the conventions laid out in [Keep a CHANGELOG][].
 
+
+## Unreleased
+
+### Fixed
+-    Fix `object[]` parameters taking precedence when should not in overload resolution
+
 ## [2.5.1][] - 2020-06-18
 
 Bugfix release.
diff --git a/src/runtime/methodbinder.cs b/src/runtime/methodbinder.cs
index b3186a3f2..2725f5f16 100644
--- a/src/runtime/methodbinder.cs
+++ b/src/runtime/methodbinder.cs
@@ -203,6 +203,16 @@ internal static int ArgPrecedence(Type t)
                 return 3000;
             }
 
+            if (t.IsArray)
+            {
+                Type e = t.GetElementType();
+                if (e == objectType)
+                {
+                    return 2500;
+                }
+                return 100 + ArgPrecedence(e);
+            }
+
             TypeCode tc = Type.GetTypeCode(t);
             // TODO: Clean up
             switch (tc)
@@ -250,16 +260,6 @@ internal static int ArgPrecedence(Type t)
                     return 40;
             }
 
-            if (t.IsArray)
-            {
-                Type e = t.GetElementType();
-                if (e == objectType)
-                {
-                    return 2500;
-                }
-                return 100 + ArgPrecedence(e);
-            }
-
             return 2000;
         }
 
diff --git a/src/testing/methodtest.cs b/src/testing/methodtest.cs
index 91836b727..9a4c408d6 100644
--- a/src/testing/methodtest.cs
+++ b/src/testing/methodtest.cs
@@ -1,5 +1,6 @@
 using System;
 using System.IO;
+using System.Linq;
 using System.Runtime.InteropServices;
 
 namespace Python.Test
@@ -84,7 +85,7 @@ public Type[] TestNullArrayConversion(Type[] v)
 
         public static string[] TestStringParamsArg(params string[] args)
         {
-            return args;
+            return args.Concat(new []{"tail"}).ToArray();
         }
 
         public static object[] TestObjectParamsArg(params object[] args)
diff --git a/src/tests/test_method.py b/src/tests/test_method.py
index 69f1b5e72..8456ddc9f 100644
--- a/src/tests/test_method.py
+++ b/src/tests/test_method.py
@@ -208,17 +208,20 @@ def test_null_array_conversion():
 def test_string_params_args():
     """Test use of string params."""
     result = MethodTest.TestStringParamsArg('one', 'two', 'three')
-    assert result.Length == 3
-    assert len(result) == 3, result
+    assert result.Length == 4
+    assert len(result) == 4, result
     assert result[0] == 'one'
     assert result[1] == 'two'
     assert result[2] == 'three'
+    # ensures params string[] overload takes precedence over params object[]
+    assert result[3] == 'tail'
 
     result = MethodTest.TestStringParamsArg(['one', 'two', 'three'])
-    assert len(result) == 3
+    assert len(result) == 4
     assert result[0] == 'one'
     assert result[1] == 'two'
     assert result[2] == 'three'
+    assert result[3] == 'tail'
 
 
 def test_object_params_args():