Fix applying SuppressIldasmAttribute by reverting strange check

Obfuscar/Obfuscator.cs

@@ -1512,15 +1512,25 @@ public void PostProcessing()
                 var module = info.Definition.MainModule;
                 var attribute = new TypeReference("System.Runtime.CompilerServices", "SuppressIldasmAttribute", module,
                     module.TypeSystem.CoreLibrary).Resolve();
-                if (attribute == null || attribute.Module != module.TypeSystem.CoreLibrary)
-                    return;
+
+                if (attribute == null)
+                {
+                    LogOutput($"Failed to resolve SuppressIldasmAttribute inside {module.Name}");
+                    continue;
+                }
+
+                // Something like this was added in the master repo, but it doesn't work
+                //if (attribute == null || attribute.Module.TypeSystem.CoreLibrary.Name != module.TypeSystem.CoreLibrary.Name) return;
 
                 CustomAttribute found = module.CustomAttributes.FirstOrDefault(existing =>
                     existing.Constructor.DeclaringType.FullName == attribute.FullName);
 
                 //Only add if it's not there already
                 if (found != null)
+                {
+                    LogOutput($"SuppressIldasmAttribute already exists for {module.Name}");
                     continue;
+                }
 
                 //Add one
                 var add = module.ImportReference(attribute.GetConstructors().FirstOrDefault(item => !item.HasParameters));

ObfuscarTest/SuppressIldasmTest.cs

@@ -0,0 +1,82 @@
+#region Copyright (c) 2007 Ryan Williams <[email protected]>
+
+/// <copyright>
+/// Copyright (c) 2007 Ryan Williams <[email protected]>
+///
+/// Permission is hereby granted, free of charge, to any person obtaining a copy
+/// of this software and associated documentation files (the "Software"), to deal
+/// in the Software without restriction, including without limitation the rights
+/// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+/// copies of the Software, and to permit persons to whom the Software is
+/// furnished to do so, subject to the following conditions:
+///
+/// The above copyright notice and this permission notice shall be included in
+/// all copies or substantial portions of the Software.
+///
+/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+/// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+/// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+/// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+/// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+/// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+/// THE SOFTWARE.
+/// </copyright>
+
+#endregion
+
+using System.IO;
+using System.Linq;
+using Mono.Cecil;
+using Obfuscar;
+using Xunit;
+using System.Runtime.CompilerServices;
+
+namespace ObfuscarTest
+{
+    public class SuppressIldasmTests
+    {
+        Obfuscator BuildAndObfuscateAssemblies(string name)
+        {
+            string xml = string.Format(
+                @"<?xml version='1.0'?>" +
+                @"<Obfuscator>" +
+                @"<Var name='InPath' value='{0}' />" +
+                @"<Var name='OutPath' value='{1}' />" +
+                @"<Var name='KeepPublicApi' value='true' />" +
+                @"<Var name='HidePrivateApi' value='true' />" +
+                @"<Var name='SuppressIldasm' value='true' />" +
+                @"<Module file='$(InPath){2}{3}.dll' />" +
+                @"</Obfuscator>", TestHelper.InputPath, TestHelper.OutputPath, Path.DirectorySeparatorChar, name);
+
+            return TestHelper.BuildAndObfuscate(name, string.Empty, xml);
+        }
+
+        [Fact]
+        public void CheckSuppressIldasm()
+        {
+            Obfuscator item = BuildAndObfuscateAssemblies("AssemblyWithInterfaces");
+            ObfuscationMap map = item.Mapping;
+
+            string assmName = "AssemblyWithInterfaces.dll";
+
+            // We do not expect input assembly to have special attribute
+            using (AssemblyDefinition inAssmDef = AssemblyDefinition.ReadAssembly(
+                Path.Combine(TestHelper.InputPath, assmName)))
+            {
+                CustomAttribute found = inAssmDef.CustomAttributes.FirstOrDefault(existing =>
+                    existing.Constructor.DeclaringType.Name == nameof(SuppressIldasmAttribute));
+                Assert.Null(found);
+
+            }
+
+            // the output assembly must have specific attribute
+            using (AssemblyDefinition outAssmDef = AssemblyDefinition.ReadAssembly(
+                    Path.Combine(item.Project.Settings.OutPath, assmName)))
+            {
+                CustomAttribute found = outAssmDef.CustomAttributes.FirstOrDefault(existing =>
+                    existing.Constructor.DeclaringType.Name == nameof(SuppressIldasmAttribute));
+                Assert.NotNull(found);
+            }
+        }
+    }
+}