adds support for nameof expression (issue #95)

adrianoc · Oct 9, 2021 · d1c0631 · d1c0631
1 parent 9c56b62
commit d1c0631
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Showing 3 changed files with 36 additions and 0 deletions.
diff --git a/Cecilifier.Core.Tests/Tests/Unit/NameOfTests.cs b/Cecilifier.Core.Tests/Tests/Unit/NameOfTests.cs
@@ -0,0 +1,19 @@
+using NUnit.Framework;
+
+namespace Cecilifier.Core.Tests.Tests.Unit
+{
+    [TestFixture]
+    public class NameOfTests : CecilifierUnitTestBase
+    {
+        [TestCase("using System; [Obsolete(nameof(Foo))] public class Foo { }", "new CustomAttributeArgument(assembly.MainModule.TypeSystem.String, \"Foo\")", TestName = "Attribute Parameter")]
+        [TestCase("public class Foo { string ConstString = nameof(ConstString); }", "Ldstr, \"ConstString\"",TestName = "Field Initialization")]
+        [TestCase("public class Foo { string Name() => nameof(Name); }", "Ldstr, \"Name\"",TestName = "Method Return")]
+        [TestCase("public class Foo { string StringInterpolation() => $\"Name={nameof(StringInterpolation)}\"; }", "??",TestName = "String Interpolation", IgnoreReason = "Depends on #107")]
+        public void Test(string code, string expectedLiteral)
+        {
+            var result = RunCecilifier(code);
+            var cecilifiedCode = result.GeneratedCode.ReadToEnd();
+            Assert.That(cecilifiedCode, Contains.Substring(expectedLiteral));
+        }
+    }
+}
diff --git a/Cecilifier.Core/AST/ExpressionVisitor.cs b/Cecilifier.Core/AST/ExpressionVisitor.cs
@@ -331,6 +331,13 @@ public override void VisitDeclarationExpression(DeclarationExpressionSyntax node
 
         public override void VisitInvocationExpression(InvocationExpressionSyntax node)
         {
+            var constantValue = Context.SemanticModel.GetConstantValue(node);
+            if (constantValue.HasValue && node.Expression is IdentifierNameSyntax { Identifier: { Text: "nameof" }} nameofExpression)
+            {
+                AddCilInstruction(ilVar, OpCodes.Ldstr, $"\"{node.ArgumentList.Arguments[0].ToFullString()}\"");
+                return;
+            }
+
             HandleMethodInvocation(node.Expression, node.ArgumentList);
             StoreTopOfStackInLocalVariableAndLoadItsAddressIfNeeded(node);
         }

diff --git a/Cecilifier.Core/Extensions/ExpressionExtensions.cs b/Cecilifier.Core/Extensions/ExpressionExtensions.cs
@@ -30,6 +30,16 @@ public override string VisitTypeOfExpression(TypeOfExpressionSyntax node)
             return _context.TypeResolver.Resolve(typeSymbol.Type);
         }
 
+        public override string? VisitInvocationExpression(InvocationExpressionSyntax node)
+        {
+            if (node.Expression is IdentifierNameSyntax { Identifier: { Text: "nameof" } } nameOf)
+            {
+                return $"\"{node.ArgumentList.Arguments[0].Expression}\"";
+            }
+
+            return string.Empty;
+        }
+
         public override string VisitMemberAccessExpression(MemberAccessExpressionSyntax node)
         {
             var type = _context.SemanticModel.GetTypeInfo(node.Expression);