[Mono-bugs] [Bug 29601][Wis] New - Type.GetConstructor doesn't look at type inheritance for constructor signature

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Changed by jonpryor@vt.edu.

http://bugzilla.ximian.com/show_bug.cgi?id=29601

--- shadow/29601	Wed Aug 28 18:55:13 2002
+++ shadow/29601.tmp.2061	Wed Aug 28 18:55:13 2002
@@ -0,0 +1,95 @@
+Bug#: 29601
+Product: Mono/Class Libraries
+Version: unspecified
+OS: Red Hat 7.3
+OS Details: 
+Status: NEW   
+Resolution: 
+Severity: 
+Priority: Wishlist
+Component: CORLIB
+AssignedTo: mono-bugs@ximian.com                            
+ReportedBy: jonpryor@vt.edu               
+QAContact: mono-bugs@ximian.com
+TargetMilestone: ---
+URL: 
+Cc: 
+Summary: Type.GetConstructor doesn't look at type inheritance for constructor signature
+
+Please fill in this template when reporting a bug, unless you know what you
+are doing.
+Description of Problem:
+
+Type.GetConstructor(System.Type[]) doesn't look at the base class of types
+when looking for a matching constructor argument list.
+
+For example, if I have a class Foo:
+
+    class Foo {
+        public Foo (TextWriter writer) { /* ... */ }
+    }
+
+I'm able to pass in a subclass of `TextWriter' in C# code:
+
+    Foo f = new Foo (new StringWriter());
+
+However, I'm unable to do the "equivalent" call through (e.g.)
+Activator.CreateInstance under Mono (it works on .NET):
+
+    TextWriter w = new StringWriter();
+    Foo f = (Foo) Activator.CreateInstance(typeof(Foo),
+        new object[] {w});
+
+This is because Type.GetConstructor(Type[]) doesn't look at the base types
+of the types passed in (see the corlib/System/Activator.cs:142, which calls
+Type.GetConstructor).
+
+Steps to reproduce the problem:
+1. Compile the following code (``mcs aci.cs'').  Note the commented section
+in Main().  If the commented line is used instead of the preceding line,
+the program behaves correctly.  This is why I believe it to be an
+inheritence-check problem.
+
+    // file: aci.cs
+
+    using System;
+    using System.IO;
+    using System.Reflection;
+
+    public class aci
+    {
+      public static void Main ()
+      {
+        Type t = typeof(ToCreate);
+        TextWriter w = new StringWriter();
+        Type[] args = new Type[1];
+        args[0] = w.GetType();
+        // args[0] = typeof(TextWriter);
+        ConstructorInfo ci = t.GetConstructor(args);
+        if (ci == null)
+          Console.WriteLine ("couldn't find constructor!");
+        else
+          Console.WriteLine ("found constructor: {0}", ci.ToString());
+      }
+    }
+
+2. Run the resulting executable on both Linux and Windows.
+3. Note that output is different.
+
+Actual Results:
+
+On Linux, the output is:
+
+    couldn't find constructor!
+
+Expected Results:
+
+    found constructor: MonoCMethod
+
+The actual output after `constructor:' may vary; .NET has different output.
+
+How often does this happen? 
+
+Always.
+
+Additional Information: