From f639e50b5cc1c20308cf72d85f18c534fa7fce31 Mon Sep 17 00:00:00 2001
From: Jonathan Pobst <jonathan.pobst@microsoft.com>
Date: Mon, 8 Jun 2020 10:22:26 -0500
Subject: [PATCH] [generator] Don't invalidate interface if we invalidate a
 static method on it.

---
 .../DefaultInterfaceMethodsTests.cs           | 35 +++++++++++++++++++
 .../GenBase.cs                                |  6 ++--
 2 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/tests/generator-Tests/Unit-Tests/DefaultInterfaceMethodsTests.cs b/tests/generator-Tests/Unit-Tests/DefaultInterfaceMethodsTests.cs
index d7b4f82db..25f737f5c 100644
--- a/tests/generator-Tests/Unit-Tests/DefaultInterfaceMethodsTests.cs
+++ b/tests/generator-Tests/Unit-Tests/DefaultInterfaceMethodsTests.cs
@@ -396,5 +396,40 @@ public void RespectNoAlternativesForInterfaces ()
 			Assert.False (writer.ToString ().Contains ("class ParentConsts"));
 			Assert.False (writer.ToString ().Contains ("class Parent"));
 		}
+
+		[Test]
+		public void DontInvalidateInterfaceDueToStaticOrDefaultMethods ()
+		{
+			// This interface contains a static and a default interface method that cannot
+			// be bound due to an unknown return type. However the user doesn't have to
+			// provide an implementation for these methods, so it's ok to bind the interface.
+
+			var xml = @"<api>
+			  <package name='com.xamarin.android' jni-name='com/xamarin/android'>
+			    <interface abstract='true' deprecated='not deprecated' final='false' name='Parent' static='false' visibility='public' jni-signature='Lcom/xamarin/android/Parent;'>
+			      <method abstract='true' deprecated='not deprecated' name='normalMethod' jni-signature='()I' return='int' static='false' transient='false' visibility='public' volatile='false'></method>
+			      <method abstract='false' deprecated='not deprecated' name='staticMethod' jni-signature='()Lfoo/bar/baz;' return='Lfoo/bar/baz;' static='true' transient='false' visibility='public' volatile='false'></method>
+			      <method abstract='false' deprecated='not deprecated' name='defaultMethod' jni-signature='()Lfoo/bar/baz;' return='Lfoo/bar/baz;' static='false' transient='false' visibility='public' volatile='false'></method>
+			    </interface>
+			  </package>
+			</api>";
+
+			var gens = ParseApiDefinition (xml);
+			var iface = gens.OfType<InterfaceGen> ().Single ();
+
+			var result = iface.Validate (options, new GenericParameterDefinitionList (), new CodeGeneratorContext ());
+
+			// Inteface should pass validation despite invalid static/default methods
+			Assert.True (result);
+
+			generator.WriteInterface (iface, string.Empty, new GenerationInfo (string.Empty, string.Empty, "MyAssembly"));
+
+			var generated = writer.ToString ();
+
+			Assert.True (generated.Contains ("interface IParent"));
+			Assert.True (generated.Contains ("NormalMethod"));
+			Assert.False (generated.Contains ("StaticMethod"));
+			Assert.False (generated.Contains ("DefaultMethod"));
+		}
 	}
 }
diff --git a/tools/generator/Java.Interop.Tools.Generator.ObjectModel/GenBase.cs b/tools/generator/Java.Interop.Tools.Generator.ObjectModel/GenBase.cs
index 95ce07828..255a37e91 100644
--- a/tools/generator/Java.Interop.Tools.Generator.ObjectModel/GenBase.cs
+++ b/tools/generator/Java.Interop.Tools.Generator.ObjectModel/GenBase.cs
@@ -677,11 +677,11 @@ protected virtual bool OnValidate (CodeGenerationOptions opt, GenericParameterDe
 			}
 			Fields = valid_fields;
 
-			// If we can't validate a default interface method it's ok to ignore it and still bind the interface
-			var method_cnt = Methods.Where (m => !m.IsInterfaceDefaultMethod).Count ();
+			// If we can't validate a static or default interface method it's ok to ignore it and still bind the interface
+			var method_cnt = Methods.Where (m => !m.IsInterfaceDefaultMethod && !m.IsStatic).Count ();
 
 			Methods = Methods.Where (m => ValidateMethod (opt, m, context)).ToList ();
-			MethodValidationFailed = method_cnt != Methods.Where (m => !m.IsInterfaceDefaultMethod).Count ();
+			MethodValidationFailed = method_cnt != Methods.Where (m => !m.IsInterfaceDefaultMethod && !m.IsStatic).Count ();
 
 			foreach (Method m in Methods) {
 				if (m.IsVirtual)