Merge pull request #15918 from stephentoub/codedom_fix

CodeDom fixes for explicit interface implementation with built-in types

4 files changed, 150 insertions, 137 deletions

diff --git a/src/System.CodeDom/src/Microsoft/CSharp/CSharpCodeGenerator.cs b/src/System.CodeDom/src/Microsoft/CSharp/CSharpCodeGenerator.cs
index 242a60a2e8..e180cb5c5a 100644
--- a/src/System.CodeDom/src/Microsoft/CSharp/CSharpCodeGenerator.cs
+++ b/src/System.CodeDom/src/Microsoft/CSharp/CSharpCodeGenerator.cs
@@ -1213,7 +1213,7 @@ namespace Microsoft.CSharp
             string name = e.Name;
             if (e.PrivateImplementationType != null)
             {
-                name = GetBaseTypeOutput(e.PrivateImplementationType) + "." + name;
+                name = GetBaseTypeOutput(e.PrivateImplementationType, preferBuiltInTypes: false) + "." + name;
             }
             OutputTypeNamePair(e.Type, name);
             Output.WriteLine(';');
@@ -1472,7 +1472,7 @@ namespace Microsoft.CSharp
             Output.Write(' ');
             if (e.PrivateImplementationType != null)
             {
-                Output.Write(GetBaseTypeOutput(e.PrivateImplementationType));
+                Output.Write(GetBaseTypeOutput(e.PrivateImplementationType, preferBuiltInTypes: false));
                 Output.Write('.');
             }
             OutputIdentifier(e.Name);
@@ -1558,7 +1558,7 @@ namespace Microsoft.CSharp
 
             if (e.PrivateImplementationType != null && !IsCurrentInterface)
             {
-                Output.Write(GetBaseTypeOutput(e.PrivateImplementationType));
+                Output.Write(GetBaseTypeOutput(e.PrivateImplementationType, preferBuiltInTypes: false));
                 Output.Write('.');
             }
 
@@ -2803,68 +2803,56 @@ namespace Microsoft.CSharp
         }
 
         // returns the type name without any array declaration.
-        private string GetBaseTypeOutput(CodeTypeReference typeRef)
+        private string GetBaseTypeOutput(CodeTypeReference typeRef, bool preferBuiltInTypes = true)
         {
             string s = typeRef.BaseType;
-            if (s.Length == 0)
-            {
-                s = "void";
-                return s;
-            }
 
-            string lowerCaseString = s.ToLower(CultureInfo.InvariantCulture).Trim();
+            if (preferBuiltInTypes)
+            {
+                if (s.Length == 0)
+                {
+                    return "void";
+                }
+
+                string lowerCaseString = s.ToLower(CultureInfo.InvariantCulture).Trim();
+
+                switch (lowerCaseString)
+                {
+                    case "system.int16":
+                        return "short";
+                    case "system.int32":
+                        return "int";
+                    case "system.int64":
+                        return "long";
+                    case "system.string":
+                        return "string";
+                    case "system.object":
+                        return "object";
+                    case "system.boolean":
+                        return "bool";
+                    case "system.void":
+                        return "void";
+                    case "system.char":
+                        return "char";
+                    case "system.byte":
+                        return "byte";
+                    case "system.uint16":
+                        return "ushort";
+                    case "system.uint32":
+                        return "uint";
+                    case "system.uint64":
+                        return "ulong";
+                    case "system.sbyte":
+                        return "sbyte";
+                    case "system.single":
+                        return "float";
+                    case "system.double":
+                        return "double";
+                    case "system.decimal":
+                        return "decimal";
+                }
+            }
 
-            switch (lowerCaseString)
-            {
-                case "system.int16":
-                    s = "short";
-                    break;
-                case "system.int32":
-                    s = "int";
-                    break;
-                case "system.int64":
-                    s = "long";
-                    break;
-                case "system.string":
-                    s = "string";
-                    break;
-                case "system.object":
-                    s = "object";
-                    break;
-                case "system.boolean":
-                    s = "bool";
-                    break;
-                case "system.void":
-                    s = "void";
-                    break;
-                case "system.char":
-                    s = "char";
-                    break;
-                case "system.byte":
-                    s = "byte";
-                    break;
-                case "system.uint16":
-                    s = "ushort";
-                    break;
-                case "system.uint32":
-                    s = "uint";
-                    break;
-                case "system.uint64":
-                    s = "ulong";
-                    break;
-                case "system.sbyte":
-                    s = "sbyte";
-                    break;
-                case "system.single":
-                    s = "float";
-                    break;
-                case "system.double":
-                    s = "double";
-                    break;
-                case "system.decimal":
-                    s = "decimal";
-                    break;
-                default:
                     // replace + with . for nested classes.
                     //
                     var sb = new StringBuilder(s.Length + 10);
@@ -2919,8 +2907,6 @@ namespace Microsoft.CSharp
                         sb.Append(CreateEscapedIdentifier(baseType.Substring(lastIndex)));
 
                     return sb.ToString();
-            }
-            return s;
         }
 
         private string GetTypeArgumentsOutput(CodeTypeReferenceCollection typeArguments)
diff --git a/src/System.CodeDom/src/Microsoft/VisualBasic/VBCodeGenerator.cs b/src/System.CodeDom/src/Microsoft/VisualBasic/VBCodeGenerator.cs
index 60f5a4f18d..a03d0b02be 100644
--- a/src/System.CodeDom/src/Microsoft/VisualBasic/VBCodeGenerator.cs
+++ b/src/System.CodeDom/src/Microsoft/VisualBasic/VBCodeGenerator.cs
@@ -1434,7 +1434,7 @@ namespace Microsoft.VisualBasic
             string eventName = e.Name;
             if (e.PrivateImplementationType != null)
             {
-                string impl = GetBaseTypeOutput(e.PrivateImplementationType);
+                string impl = GetBaseTypeOutput(e.PrivateImplementationType, preferBuiltInTypes: false);
                 impl = impl.Replace('.', '_');
                 e.Name = impl + "_" + e.Name;
             }
@@ -1561,7 +1561,7 @@ namespace Microsoft.VisualBasic
             string methodName = e.Name;
             if (e.PrivateImplementationType != null)
             {
-                string impl = GetBaseTypeOutput(e.PrivateImplementationType);
+                string impl = GetBaseTypeOutput(e.PrivateImplementationType, preferBuiltInTypes: false);
                 impl = impl.Replace('.', '_');
                 e.Name = impl + "_" + e.Name;
             }
@@ -1714,7 +1714,7 @@ namespace Microsoft.VisualBasic
             string propName = e.Name;
             if (e.PrivateImplementationType != null)
             {
-                string impl = GetBaseTypeOutput(e.PrivateImplementationType);
+                string impl = GetBaseTypeOutput(e.PrivateImplementationType, preferBuiltInTypes: false);
                 impl = impl.Replace('.', '_');
                 e.Name = impl + "_" + e.Name;
             }
@@ -2399,80 +2399,56 @@ namespace Microsoft.VisualBasic
             return name;
         }
 
-        private string GetBaseTypeOutput(CodeTypeReference typeRef)
+        private string GetBaseTypeOutput(CodeTypeReference typeRef, bool preferBuiltInTypes = true)
         {
             string baseType = typeRef.BaseType;
 
-            if (baseType.Length == 0)
-            {
-                return "Void";
-            }
-            else if (string.Equals(baseType, "System.Byte", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Byte";
-            }
-            else if (string.Equals(baseType, "System.SByte", StringComparison.OrdinalIgnoreCase))
-            {
-                return "SByte";
-            }
-            else if (string.Equals(baseType, "System.Int16", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Short";
-            }
-            else if (string.Equals(baseType, "System.Int32", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Integer";
-            }
-            else if (string.Equals(baseType, "System.Int64", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Long";
-            }
-            else if (string.Equals(baseType, "System.UInt16", StringComparison.OrdinalIgnoreCase))
-            {
-                return "UShort";
-            }
-            else if (string.Equals(baseType, "System.UInt32", StringComparison.OrdinalIgnoreCase))
-            {
-                return "UInteger";
-            }
-            else if (string.Equals(baseType, "System.UInt64", StringComparison.OrdinalIgnoreCase))
-            {
-                return "ULong";
-            }
-            else if (string.Equals(baseType, "System.String", StringComparison.OrdinalIgnoreCase))
-            {
-                return "String";
-            }
-            else if (string.Equals(baseType, "System.DateTime", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Date";
-            }
-            else if (string.Equals(baseType, "System.Decimal", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Decimal";
-            }
-            else if (string.Equals(baseType, "System.Single", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Single";
-            }
-            else if (string.Equals(baseType, "System.Double", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Double";
-            }
-            else if (string.Equals(baseType, "System.Boolean", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Boolean";
-            }
-            else if (string.Equals(baseType, "System.Char", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Char";
-            }
-            else if (string.Equals(baseType, "System.Object", StringComparison.OrdinalIgnoreCase))
-            {
-                return "Object";
+            if (preferBuiltInTypes)
+            {
+                if (baseType.Length == 0)
+                {
+                    return "Void";
+                }
+
+                string lowerCaseString = baseType.ToLowerInvariant();
+
+                switch (lowerCaseString)
+                {
+                    case "system.byte":
+                        return "Byte";
+                    case "system.sbyte":
+                        return "SByte";
+                    case "system.int16":
+                        return "Short";
+                    case "system.int32":
+                        return "Integer";
+                    case "system.int64":
+                        return "Long";
+                    case "system.uint16":
+                        return "UShort";
+                    case "system.uint32":
+                        return "UInteger";
+                    case "system.uint64":
+                        return "ULong";
+                    case "system.string":
+                        return "String";
+                    case "system.datetime":
+                        return "Date";
+                    case "system.decimal":
+                        return "Decimal";
+                    case "system.single":
+                        return "Single";
+                    case "system.double":
+                        return "Double";
+                    case "system.boolean":
+                        return "Boolean";
+                    case "system.char":
+                        return "Char";
+                    case "system.object":
+                        return "Object";
+                }
             }
-            else
-            {
+
                 var sb = new StringBuilder(baseType.Length + 10);
                 if ((typeRef.Options & CodeTypeReferenceOptions.GlobalReference) != 0)
                 {
@@ -2525,7 +2501,6 @@ namespace Microsoft.VisualBasic
                 }
 
                 return sb.ToString();
-            }
         }
 
         private string GetTypeOutputWithoutArrayPostFix(CodeTypeReference typeRef)
diff --git a/src/System.CodeDom/tests/CSharpCodeGenerationTests.cs b/src/System.CodeDom/tests/CSharpCodeGenerationTests.cs
index bc36ebccaf..38777f60e4 100644
--- a/src/System.CodeDom/tests/CSharpCodeGenerationTests.cs
+++ b/src/System.CodeDom/tests/CSharpCodeGenerationTests.cs
@@ -448,6 +448,32 @@ namespace System.CodeDom.Tests
                   }");
         }
 
+        [SkipOnTargetFramework(TargetFrameworkMonikers.NetFramework, ".NET Framework outputs C# keywords rather than type names")]
+        [Theory]
+        [InlineData(typeof(byte), "void System.Byte.MyMethod() { }")]
+        [InlineData(typeof(short), "void System.Int16.MyMethod() { }")]
+        [InlineData(typeof(ushort), "void System.UInt16.MyMethod() { }")]
+        [InlineData(typeof(int), "void System.Int32.MyMethod() { }")]
+        [InlineData(typeof(uint), "void System.UInt32.MyMethod() { }")]
+        [InlineData(typeof(long), "void System.Int64.MyMethod() { }")]
+        [InlineData(typeof(ulong), "void System.UInt64.MyMethod() { }")]
+        [InlineData(typeof(string), "void System.String.MyMethod() { }")]
+        [InlineData(typeof(object), "void System.Object.MyMethod() { }")]
+        [InlineData(typeof(bool), "void System.Boolean.MyMethod() { }")]
+        [InlineData(typeof(void), "void System.Void.MyMethod() { }")]
+        [InlineData(typeof(char), "void System.Char.MyMethod() { }")]
+        [InlineData(typeof(float), "void System.Single.MyMethod() { }")]
+        [InlineData(typeof(double), "void System.Double.MyMethod() { }")]
+        [InlineData(typeof(decimal), "void System.Decimal.MyMethod() { }")]
+        public void ExplicitImplementation(Type type, string expectedResult)
+        {
+            AssertEqual(new CodeMemberMethod()
+            {
+                Name = "MyMethod",
+                PrivateImplementationType = new CodeTypeReference(type)
+            }, expectedResult);
+        }
+
         [Fact]
         public void Arrays_SingleDimensional_PrimitiveTypes()
         {
diff --git a/src/System.CodeDom/tests/VBCodeGenerationTests.cs b/src/System.CodeDom/tests/VBCodeGenerationTests.cs
index 43e752c1b9..619694b8ba 100644
--- a/src/System.CodeDom/tests/VBCodeGenerationTests.cs
+++ b/src/System.CodeDom/tests/VBCodeGenerationTests.cs
@@ -416,6 +416,32 @@ namespace System.CodeDom.Tests
                   End Namespace");
         }
 
+        [SkipOnTargetFramework(TargetFrameworkMonikers.NetFramework, ".NET Framework outputs C# keywords rather than type names")]
+        [Theory]
+        [InlineData(typeof(byte), "Sub System_[Byte]_MyMethod() Implements Byte.MyMethod End Sub")]
+        [InlineData(typeof(short), "Sub System_Int16_MyMethod() Implements Short.MyMethod End Sub")]
+        [InlineData(typeof(ushort), "Sub System_UInt16_MyMethod() Implements UShort.MyMethod End Sub")]
+        [InlineData(typeof(int), "Sub System_Int32_MyMethod() Implements Integer.MyMethod End Sub")]
+        [InlineData(typeof(uint), "Sub System_UInt32_MyMethod() Implements UInteger.MyMethod End Sub")]
+        [InlineData(typeof(long), "Sub System_Int64_MyMethod() Implements Long.MyMethod End Sub")]
+        [InlineData(typeof(ulong), "Sub System_UInt64_MyMethod() Implements ULong.MyMethod End Sub")]
+        [InlineData(typeof(string), "Sub System_[String]_MyMethod() Implements String.MyMethod End Sub")]
+        [InlineData(typeof(object), "Sub System_[Object]_MyMethod() Implements Object.MyMethod End Sub")]
+        [InlineData(typeof(bool), "Sub System_[Boolean]_MyMethod() Implements Boolean.MyMethod End Sub")]
+        [InlineData(typeof(void), "Sub System_Void_MyMethod() Implements System.Void.MyMethod End Sub")]
+        [InlineData(typeof(char), "Sub System_[Char]_MyMethod() Implements Char.MyMethod End Sub")]
+        [InlineData(typeof(float), "Sub System_[Single]_MyMethod() Implements Single.MyMethod End Sub")]
+        [InlineData(typeof(double), "Sub System_[Double]_MyMethod() Implements Double.MyMethod End Sub")]
+        [InlineData(typeof(decimal), "Sub System_[Decimal]_MyMethod() Implements Decimal.MyMethod End Sub")]
+        public void ExplicitImplementation_BuiltIns_UsesTypeNamesForBetterCompilerHandling(Type type, string expectedResult)
+        {
+            AssertEqual(new CodeMemberMethod()
+            {
+                Name = "MyMethod",
+                PrivateImplementationType = new CodeTypeReference(type)
+            }, expectedResult);
+        }
+
         [Fact]
         public void Arrays_SingleDimensional_PrimitiveTypes()
         {