Add missing conversions

Author: jcouv

src/Compilers/CSharp/Portable/Lowering/LocalRewriter/LocalRewriter.PatternLocalRewriter.cs

@@ -152,6 +152,7 @@ protected BoundExpression LowerEvaluation(BoundDagEvaluation evaluation)
                             PropertySymbol property = p.Property;
                             var outputTemp = new BoundDagTemp(p.Syntax, property.Type, p);
                             BoundExpression output = _tempAllocator.GetTemp(outputTemp);
+                            input = _factory.ConvertReceiverForExtensionMemberIfNeeded(property, input);
                             return _factory.AssignmentExpression(output, _localRewriter.MakePropertyAccess(_factory.Syntax, input, property, LookupResultKind.Viable, property.Type, isLeftOfAssignment: false));
                         }
 
@@ -190,6 +191,7 @@ void addArg(RefKind refKind, BoundExpression expression)
                                 addArg(RefKind.Out, _tempAllocator.GetTemp(outputTemp));
                             }
 
+                            receiver = _factory.ConvertReceiverForExtensionMemberIfNeeded(method, receiver);
                             return _factory.Call(receiver, method, refKindBuilder.ToImmutableAndFree(), argBuilder.ToImmutableAndFree());
                         }
 

src/Compilers/CSharp/Portable/Lowering/LocalRewriter/LocalRewriter_FixedStatement.cs

@@ -355,6 +355,7 @@ private BoundStatement InitializeFixedStatementGetPinnable(
             }
 
             // .GetPinnable()
+            callReceiver = factory.ConvertReceiverForExtensionMemberIfNeeded(getPinnableMethod, callReceiver);
             var getPinnableCall = getPinnableMethod.IsStatic ?
                 factory.Call(null, getPinnableMethod, callReceiver) :
                 factory.Call(callReceiver, getPinnableMethod);

src/Compilers/CSharp/Portable/Lowering/LocalRewriter/LocalRewriter_ObjectOrCollectionInitializerExpression.cs

@@ -702,8 +702,7 @@ private BoundExpression MakeObjectInitializerMemberAccess(
                          _compilation.Conversions.HasImplicitConversionToOrImplementsVarianceCompatibleInterface(rewrittenReceiver.Type, memberSymbol.ContainingType, ref discardedUseSiteInfo, out _));
             // It is possible there are use site diagnostics from the above, but none that we need report as we aren't generating code for the conversion
 #endif
-            // Tracked by https://github.com/dotnet/roslyn/issues/76130 : handle creating a conversion on receiver
-            // TODO2
+            rewrittenReceiver = _factory.ConvertReceiverForExtensionMemberIfNeeded(memberSymbol, rewrittenReceiver);
 
             switch (memberSymbol.Kind)
             {

src/Compilers/CSharp/Portable/Lowering/SyntheticBoundNodeFactory.cs

@@ -431,6 +431,23 @@ public BoundExpression AssignmentExpression(BoundExpression left, BoundExpressio
             return AssignmentExpression(Syntax, left, right, isRef: isRef, wasCompilerGenerated: true);
         }
 
+        public BoundExpression ConvertReceiverForExtensionMemberIfNeeded(Symbol member, BoundExpression receiver)
+        {
+            if (member.GetIsNewExtensionMember())
+            {
+                ParameterSymbol? extensionParameter = member.ContainingType.ExtensionParameter;
+                Debug.Assert(extensionParameter is not null);
+#if DEBUG
+                var discardedUseSiteInfo = CompoundUseSiteInfo<AssemblySymbol>.Discarded;
+                Debug.Assert(Conversions.IsValidExtensionMethodThisArgConversion(this.Compilation.Conversions.ClassifyConversionFromType(receiver.Type, extensionParameter.Type, isChecked: false, ref discardedUseSiteInfo)));
+#endif
+
+                return this.Convert(extensionParameter.Type, receiver);
+            }
+
+            return receiver;
+        }
+
         /// <summary>
         /// Creates a general assignment that might be instrumented.
         /// </summary>

src/Compilers/CSharp/Test/Emit3/Semantics/ExtensionTests.cs

@@ -12871,17 +12871,17 @@ static class E
     }
 }
 """;
-        // Tracked by https://github.com/dotnet/roslyn/issues/76130 : handle conversion on receiver
         try
         {
+            // Tracked by https://github.com/dotnet/roslyn/issues/76130 : assertion in NullableWalker
             var comp = CreateCompilation(src);
             CompileAndVerify(comp, expectedOutput: "42").VerifyDiagnostics();
         }
         catch (InvalidOperationException)
         {
             return;
         }
-        Assert.False(true);
+        Assert.True(false);
     }
 
     [Fact]
@@ -20926,17 +20926,8 @@ static class E
     }
 }
 """;
-        // Tracked by https://github.com/dotnet/roslyn/issues/76130 : handle conversion on receiver
-        try
-        {
-            var comp = CreateCompilation(text, options: TestOptions.UnsafeReleaseExe);
-            CompileAndVerify(comp, expectedOutput: "pin 2", verify: Verification.Skipped).VerifyDiagnostics();
-        }
-        catch (InvalidOperationException)
-        {
-            return;
-        }
-        Assert.False(true);
+        var comp = CreateCompilation(text, options: TestOptions.UnsafeReleaseExe);
+        CompileAndVerify(comp, expectedOutput: "pin 2", verify: Verification.Skipped).VerifyDiagnostics();
     }
 
     [Fact]
@@ -22136,7 +22127,6 @@ public void ExtensionMemberLookup_Patterns()
     {
         var src = """
 var c = new C();
-
 _ = c is { Property: 42 };
 
 class C { }
@@ -22166,7 +22156,6 @@ public void ExtensionMemberLookup_Patterns_Conversion()
     {
         var src = """
 var c = new C();
-
 _ = c is { Property: 42 };
 
 class C { }
@@ -22182,17 +22171,8 @@ public int Property
     }
 }
 """;
-        // Tracked by https://github.com/dotnet/roslyn/issues/76130 : handle conversion on receiver
-        try
-        {
-            var comp = CreateCompilation(src);
-            CompileAndVerify(comp, expectedOutput: "property").VerifyDiagnostics();
-        }
-        catch (InvalidOperationException)
-        {
-            return;
-        }
-        Assert.False(true);
+        var comp = CreateCompilation(src);
+        CompileAndVerify(comp, expectedOutput: "property").VerifyDiagnostics();
     }
 
     [Fact]
@@ -22230,6 +22210,66 @@ static class E2
         Assert.Equal("System.Int32 E2.<>E__0.Property2 { get; }", model.GetSymbolInfo(expressionColon.Expression).Symbol.ToTestDisplayString());
     }
 
+    [Fact]
+    public void ExtensionMemberLookup_Patterns_ExtendedPropertyPattern_Conversion()
+    {
+        var src = """
+var c = new C();
+
+_ = c is { Property.Property2: 43 };
+
+class C { }
+
+static class E1
+{
+    extension(object o)
+    {
+        public int Property { get { System.Console.Write("property "); return 42; } }
+    }
+}
+
+static class E2
+{
+    extension(int i)
+    {
+        public int Property2 { get { System.Console.Write("property2"); return 43; } }
+    }
+}
+""";
+        var comp = CreateCompilation(src);
+        CompileAndVerify(comp, expectedOutput: "property property2").VerifyDiagnostics();
+    }
+
+    [Fact]
+    public void ExtensionMemberLookup_Patterns_ExtendedPropertyPattern_Conversion_02()
+    {
+        var src = """
+var c = new C();
+
+_ = c is { Property.Property2: 43 };
+
+class C { }
+
+static class E1
+{
+    extension(C c)
+    {
+        public C Property { get { System.Console.Write("property "); return c; } }
+    }
+}
+
+static class E2
+{
+    extension(object o)
+    {
+        public int Property2 { get { System.Console.Write("property2"); return 43; } }
+    }
+}
+""";
+        var comp = CreateCompilation(src);
+        CompileAndVerify(comp, expectedOutput: "property property2").VerifyDiagnostics();
+    }
+
     [Fact]
     public void ExtensionMemberLookup_Patterns_ListPattern_NoInstanceLength()
     {
@@ -22269,9 +22309,7 @@ public int Length
     public void ExtensionMemberLookup_ObjectInitializer()
     {
         var src = """
-/*<bind>*/
 _ = new C() { Property = 42 };
-/*</bind>*/
 
 class C { }
 
@@ -22297,9 +22335,7 @@ static class E
     public void ExtensionMemberLookup_ObjectInitializer_Conversion()
     {
         var src = """
-/*<bind>*/
 _ = new C() { Property = 42 };
-/*</bind>*/
 
 class C { }
 
@@ -22312,17 +22348,8 @@ static class E
 }
 """;
 
-        // Tracked by https://github.com/dotnet/roslyn/issues/76130 : handle conversion on receiver
-        try
-        {
-            var comp = CreateCompilation(src);
-            CompileAndVerify(comp, expectedOutput: "property").VerifyDiagnostics();
-        }
-        catch (InvalidOperationException)
-        {
-            return;
-        }
-        Assert.False(true);
+        var comp = CreateCompilation(src);
+        CompileAndVerify(comp, expectedOutput: "property").VerifyDiagnostics();
     }
 
     [Fact]
@@ -38561,15 +38588,17 @@ public class MyCollection : IEnumerable<object>
     IEnumerator IEnumerable.GetEnumerator() => throw null!;
 }
 """;
+        // Tracked by https://github.com/dotnet/roslyn/issues/78452 : assertion hit during nullability analysis
         try
         {
-            // Assertion tracked by https://github.com/dotnet/roslyn/issues/78452
             comp = CreateCompilation(src);
             comp.VerifyEmitDiagnostics();
         }
         catch (InvalidOperationException)
         {
+            return;
         }
+        Assert.True(false);
     }
 
     [Fact]
@@ -38649,17 +38678,11 @@ public object Property { set { } }
 }
 """;
 
-        // Tracked by https://github.com/dotnet/roslyn/issues/76130 : handle conversion on receiver
-        try
-        {
-            var comp = CreateCompilation(src);
-            comp.VerifyEmitDiagnostics();
-        }
-        catch (InvalidOperationException)
-        {
-            return;
-        }
-        Assert.False(true);
+        var comp = CreateCompilation(src);
+        comp.VerifyEmitDiagnostics(
+            // (4,31): warning CS8601: Possible null reference assignment.
+            // _ = new S() with { Property = oNull };
+            Diagnostic(ErrorCode.WRN_NullReferenceAssignment, "oNull").WithLocation(4, 31));
     }
 
     [Fact]
@@ -38685,17 +38708,11 @@ public int Property { set { } }
 }
 """;
 
-        // Tracked by https://github.com/dotnet/roslyn/issues/76130 : handle conversion on receiver
-        try
-        {
-            var comp = CreateCompilation(src);
-            comp.VerifyEmitDiagnostics();
-        }
-        catch (InvalidOperationException)
-        {
-            return;
-        }
-        Assert.False(true);
+        var comp = CreateCompilation(src);
+        comp.VerifyEmitDiagnostics(
+            // (4,5): warning CS8602: Dereference of a possibly null reference.
+            // _ = cNull with { Property = 42 };
+            Diagnostic(ErrorCode.WRN_NullReferenceReceiver, "cNull").WithLocation(4, 5));
     }
 
     [Fact]
@@ -38712,6 +38729,37 @@ public void Nullability_With_03()
 
 record C { }
 
+static class E
+{
+    extension(object? o)
+    {
+        public int Property { set { } }
+    }
+}
+""";
+
+        // Tracked by https://github.com/dotnet/roslyn/issues/76130 : unexpected nullability warning
+        var comp = CreateCompilation(src);
+        comp.VerifyEmitDiagnostics(
+            // (4,5): warning CS8602: Dereference of a possibly null reference.
+            // _ = cNull with { Property = 42 };
+            Diagnostic(ErrorCode.WRN_NullReferenceReceiver, "cNull").WithLocation(4, 5));
+    }
+
+    [Fact]
+    public void Nullability_With_04()
+    {
+        var src = """
+#nullable enable
+
+C? cNull = null;
+_ = cNull with { Property = 42 };
+
+C cNotNull = new C();
+_ = cNotNull with { Property = 42 };
+
+record C { }
+
 static class E
 {
     extension<T>(T t)
@@ -38729,7 +38777,7 @@ public int Property { set { } }
     }
 
     [Fact]
-    public void Nullability_With_04()
+    public void Nullability_With_05()
     {
         var src = """
 #nullable enable