From cf82b8fbe468264332993150ed8ac4ce1150ea8f Mon Sep 17 00:00:00 2001
From: Gen Lu <gen.lu@microsoft.com>
Date: Fri, 7 Apr 2017 18:09:24 -0700
Subject: [PATCH] More VB tests for IArgument

---
 .../IOperation/IOperationTests_IArgument.cs   |   2 +-
 .../IOperation/IOperationTests_IArgument.vb   | 337 ++++++++++++++----
 2 files changed, 274 insertions(+), 65 deletions(-)

diff --git a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IArgument.cs b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IArgument.cs
index f2e49a755a3..b7f4e67d142 100644
--- a/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IArgument.cs
+++ b/src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IArgument.cs
@@ -11,7 +11,7 @@ namespace Microsoft.CodeAnalysis.CSharp.UnitTests
     public partial class IOperationTests : SemanticModelTestBase
     {
         [Fact]
-        public void PositinalArgument()
+        public void PositionalArgument()
         {
             string source = @"
 class P
diff --git a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IArgument.vb b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IArgument.vb
index 3cd24be7245..b159e7f119a 100644
--- a/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IArgument.vb
+++ b/src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IArgument.vb
@@ -9,23 +9,129 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.UnitTests.Semantics
         Inherits SemanticModelTestBase
 
         <Fact()>
-        Public Sub ExplicitSimpleArgument()
+        Public Sub PositionalArgument()
             Dim source = <![CDATA[
-Class P
+Class Program
     Sub M1()
-        M2(1, 2.0)'BIND:"M2(1, 2.0)"
+        M2(1, 0.0)'BIND:"M2(1, 0.0)"
     End Sub
 
-    Sub M2(x As Integer, y As Double)
+    Sub M2(a As Integer, b As Double)
     End Sub
 End Class]]>.Value
 
             Dim expectedOperationTree = <![CDATA[
-IInvocationExpression ( Sub P.M2(x As System.Int32, y As System.Double)) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1, 2.0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
-  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: x) (OperationKind.Argument) (Syntax: '1')
+IInvocationExpression ( Sub Program.M2(a As System.Int32, b As System.Double)) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1, 0.0)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
       ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
-    IArgument (ArgumentKind.Explicit Matching Parameter: y) (OperationKind.Argument) (Syntax: '2.0')
+    IArgument (ArgumentKind.Explicit Matching Parameter: b) (OperationKind.Argument) (Syntax: '0.0')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 0) (Syntax: '0.0')
+]]>.Value
+
+            Dim expectedDiagnostics = String.Empty
+
+            VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
+        End Sub
+
+        <Fact()>
+        Public Sub PositionalArgumentWithDefaultValue()
+            Dim source = <![CDATA[
+Class Program
+    Sub M1()
+        M2(1)'BIND:"M2(1)"
+    End Sub
+
+    Sub M2(a As Integer, Optional b As Double = 0.0)
+    End Sub
+End Class]]>.Value
+
+            Dim expectedOperationTree = <![CDATA[
+IInvocationExpression ( Sub Program.M2(a As System.Int32, [b As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
+      ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
+    IArgument (ArgumentKind.DefaultValue Matching Parameter: b) (OperationKind.Argument) (Syntax: 'M2')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 0) (Syntax: 'M2')
+]]>.Value
+
+            Dim expectedDiagnostics = String.Empty
+
+            VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
+        End Sub
+
+        <Fact()>
+        Public Sub NamedArgumentListedInParameterOrder()
+            Dim source = <![CDATA[
+Class Program
+    Sub M1()
+        M2(a:=1, b:=1.0)'BIND:"M2(a:=1, b:=1.0)"
+    End Sub
+
+    Sub M2(a As Integer, Optional b As Double = 0.0)
+    End Sub
+End Class]]>.Value
+
+            Dim expectedOperationTree = <![CDATA[
+IInvocationExpression ( Sub Program.M2(a As System.Int32, [b As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(a:=1, b:=1.0)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
+      ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
+    IArgument (ArgumentKind.Explicit Matching Parameter: b) (OperationKind.Argument) (Syntax: '1.0')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 1) (Syntax: '1.0')
+]]>.Value
+
+            Dim expectedDiagnostics = String.Empty
+
+            VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
+        End Sub
+
+        <Fact()>
+        Public Sub NamedArgumentListedOutOfParameterOrder()
+            Dim source = <![CDATA[
+Class Program
+    Sub M1()
+        M2(b:=1.0, a:=0)'BIND:"M2(b:=1.0, a:=0)"
+    End Sub
+
+    Sub M2(a As Integer, Optional b As Double = 0.0)
+    End Sub
+End Class]]>.Value
+
+            Dim expectedOperationTree = <![CDATA[
+IInvocationExpression ( Sub Program.M2(a As System.Int32, [b As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(b:=1.0, a:=0)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: '0')
+      ILiteralExpression (Text: 0) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: '0')
+    IArgument (ArgumentKind.Explicit Matching Parameter: b) (OperationKind.Argument) (Syntax: '1.0')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 1) (Syntax: '1.0')
+]]>.Value
+
+            Dim expectedDiagnostics = String.Empty
+
+            VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
+        End Sub
+
+        <Fact()>
+        Public Sub NamedArgumentInParameterOrderWithDefaultValue()
+            Dim source = <![CDATA[
+Class Program
+    Sub M1()
+        M2(b:=1.0, c:=2.0)'BIND:"M2(b:=1.0, c:=2.0)"
+    End Sub
+
+    Sub M2(Optional a As Integer = 0, Optional b As Double = 0.0, Optional c As Double = 0.0)
+    End Sub
+End Class]]>.Value
+
+            Dim expectedOperationTree = <![CDATA[
+IInvocationExpression ( Sub Program.M2([a As System.Int32 = 0], [b As System.Double = 0], [c As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(b:=1.0, c:=2.0)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(3): IArgument (ArgumentKind.DefaultValue Matching Parameter: a) (OperationKind.Argument) (Syntax: 'M2')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: 'M2')
+    IArgument (ArgumentKind.Explicit Matching Parameter: b) (OperationKind.Argument) (Syntax: '1.0')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 1) (Syntax: '1.0')
+    IArgument (ArgumentKind.Explicit Matching Parameter: c) (OperationKind.Argument) (Syntax: '2.0')
       ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 2) (Syntax: '2.0')
 ]]>.Value
 
@@ -35,26 +141,26 @@ IInvocationExpression ( Sub P.M2(x As System.Int32, y As System.Double)) (Operat
         End Sub
 
         <Fact()>
-        Public Sub ExplicitSimpleArgumentByName()
+        Public Sub NamedArgumentInParameterOrderWithDefaultValueUsingOmittedSyntax()
             Dim source = <![CDATA[
-Class P
+Class Program
     Sub M1()
-        M2(y:=1, x:=2.0)'BIND:"M2(y:=1, x:=2.0)"
+        M2(, b:=1.0, c:=2.0)'BIND:"M2(, b:=1.0, c:=2.0)"
     End Sub
 
-    Sub M2(x As Integer, y As Double)
+    Sub M2(Optional a As Integer = 0, Optional b As Double = 0.0, Optional c As Double = 0.0)
     End Sub
 End Class]]>.Value
 
             Dim expectedOperationTree = <![CDATA[
-IInvocationExpression ( Sub P.M2(x As System.Int32, y As System.Double)) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(y:=1, x:=2.0)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
-  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: x) (OperationKind.Argument) (Syntax: '2.0')
-      IConversionExpression (ConversionKind.Basic, Implicit) (OperationKind.ConversionExpression, Type: System.Int32, Constant: 2) (Syntax: '2.0')
-        ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 2) (Syntax: '2.0')
-    IArgument (ArgumentKind.Explicit Matching Parameter: y) (OperationKind.Argument) (Syntax: '1')
-      IConversionExpression (ConversionKind.Basic, Implicit) (OperationKind.ConversionExpression, Type: System.Double, Constant: 1) (Syntax: '1')
-        ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
+IInvocationExpression ( Sub Program.M2([a As System.Int32 = 0], [b As System.Double = 0], [c As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(, b:=1.0, c:=2.0)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(3): IArgument (ArgumentKind.DefaultValue Matching Parameter: a) (OperationKind.Argument) (Syntax: 'M2')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: 'M2')
+    IArgument (ArgumentKind.Explicit Matching Parameter: b) (OperationKind.Argument) (Syntax: '1.0')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 1) (Syntax: '1.0')
+    IArgument (ArgumentKind.Explicit Matching Parameter: c) (OperationKind.Argument) (Syntax: '2.0')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 2) (Syntax: '2.0')
 ]]>.Value
 
             Dim expectedDiagnostics = String.Empty
@@ -63,24 +169,26 @@ IInvocationExpression ( Sub P.M2(x As System.Int32, y As System.Double)) (Operat
         End Sub
 
         <Fact()>
-        Public Sub XXXX()
+        Public Sub NamedArgumentOutOfParameterOrderWithDefaultValue()
             Dim source = <![CDATA[
-Class P
+Class Program
     Sub M1()
-        M2(y:=2)'BIND:"M2(y:=2)"
+        M2(b:=2.0)'BIND:"M2(b:=2.0)"
     End Sub
 
-    Sub M2(Optional x As Integer = 0, Optional y As Integer = 0)
+    Sub M2(Optional a As Integer = 0, Optional b As Double = 0.0, Optional c As Double = 0.0)
     End Sub
 End Class]]>.Value
 
             Dim expectedOperationTree = <![CDATA[
-IInvocationExpression ( Sub P.M2([x As System.Int32 = 0], [y As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(y:=2)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
-  Arguments(2): IArgument (ArgumentKind.DefaultValue Matching Parameter: x) (OperationKind.Argument) (Syntax: 'M2')
+IInvocationExpression ( Sub Program.M2([a As System.Int32 = 0], [b As System.Double = 0], [c As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(b:=2.0)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(3): IArgument (ArgumentKind.DefaultValue Matching Parameter: a) (OperationKind.Argument) (Syntax: 'M2')
       ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: 'M2')
-    IArgument (ArgumentKind.Explicit Matching Parameter: y) (OperationKind.Argument) (Syntax: '2')
-      ILiteralExpression (Text: 2) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 2) (Syntax: '2')
+    IArgument (ArgumentKind.Explicit Matching Parameter: b) (OperationKind.Argument) (Syntax: '2.0')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 2) (Syntax: '2.0')
+    IArgument (ArgumentKind.DefaultValue Matching Parameter: c) (OperationKind.Argument) (Syntax: 'M2')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 0) (Syntax: 'M2')
 ]]>.Value
 
             Dim expectedDiagnostics = String.Empty
@@ -89,24 +197,26 @@ IInvocationExpression ( Sub P.M2([x As System.Int32 = 0], [y As System.Int32 = 0
         End Sub
 
         <Fact()>
-        Public Sub DefaultArgument()
+        Public Sub NamedAndPositionalArgumentsWithDefaultValue()
             Dim source = <![CDATA[
-Class P
+Class Program
     Sub M1()
-        M2(1)'BIND:"M2(1)"
+        M2(1, c:=2.0)'BIND:"M2(1, c:=2.0)"
     End Sub
 
-    Sub M2(x As Integer, Optional y As Double = 0.0)
+    Sub M2(Optional a As Integer = 0, Optional b As Double = 0.0, Optional c As Double = 0.0)
     End Sub
 End Class]]>.Value
 
             Dim expectedOperationTree = <![CDATA[
-IInvocationExpression ( Sub P.M2(x As System.Int32, [y As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
-  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: x) (OperationKind.Argument) (Syntax: '1')
+IInvocationExpression ( Sub Program.M2([a As System.Int32 = 0], [b As System.Double = 0], [c As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1, c:=2.0)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(3): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
       ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
-    IArgument (ArgumentKind.DefaultValue Matching Parameter: y) (OperationKind.Argument) (Syntax: 'M2')
+    IArgument (ArgumentKind.DefaultValue Matching Parameter: b) (OperationKind.Argument) (Syntax: 'M2')
       ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 0) (Syntax: 'M2')
+    IArgument (ArgumentKind.Explicit Matching Parameter: c) (OperationKind.Argument) (Syntax: '2.0')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 2) (Syntax: '2.0')
 ]]>.Value
 
             Dim expectedDiagnostics = String.Empty
@@ -115,28 +225,22 @@ IInvocationExpression ( Sub P.M2(x As System.Int32, [y As System.Double = 0])) (
         End Sub
 
         <Fact()>
-        Public Sub ParamArrayArgument()
+        Public Sub PositionalByRefNonModifiableArgument()
             Dim source = <![CDATA[
-Class P
+Class Program
     Sub M1()
-        M2(1, 2, 3)'BIND:"M2(1, 2, 3)"
+        M2(1)'BIND:"M2(1)"
     End Sub
 
-    Sub M2(x As Integer, ParamArray array As Integer())
+    Sub M2(ByRef Optional a As Integer = 0)
     End Sub
 End Class]]>.Value
 
             Dim expectedOperationTree = <![CDATA[
-IInvocationExpression ( Sub P.M2(x As System.Int32, ParamArray array As System.Int32())) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1, 2, 3)')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
-  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: x) (OperationKind.Argument) (Syntax: '1')
+IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(1): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: '1')
       ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
-    IArgument (ArgumentKind.ParamArray Matching Parameter: array) (OperationKind.Argument) (Syntax: 'M2(1, 2, 3)')
-      IArrayCreationExpression (Element Type: System.Int32) (OperationKind.ArrayCreationExpression, Type: System.Int32()) (Syntax: 'M2(1, 2, 3)')
-        Dimension Sizes(1): ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 2) (Syntax: 'M2(1, 2, 3)')
-        Initializer: IArrayInitializer (OperationKind.ArrayInitializer) (Syntax: 'M2(1, 2, 3)')
-            Element Values(2): ILiteralExpression (Text: 2) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 2) (Syntax: '2')
-              ILiteralExpression (Text: 3) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 3) (Syntax: '3')
 ]]>.Value
 
             Dim expectedDiagnostics = String.Empty
@@ -144,29 +248,103 @@ IInvocationExpression ( Sub P.M2(x As System.Int32, ParamArray array As System.I
             VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
         End Sub
 
+
         <Fact()>
-        Public Sub ArrayAsParamsArrayArgument()
+        Public Sub PositionalByRefModifiableArgument()
             Dim source = <![CDATA[
-Class P
+Class Program
     Sub M1()
-        M2(1, New Integer() {2, 3})'BIND:"M2(1, New Integer() {2, 3})"
+        Dim x = 1
+        M2(x)'BIND:"M2(x)"
     End Sub
 
-    Sub M2(x As Integer, ParamArray array As Integer())
+    Sub M2(ByRef Optional a As Integer = 0)
     End Sub
 End Class]]>.Value
 
             Dim expectedOperationTree = <![CDATA[
-IInvocationExpression ( Sub P.M2(x As System.Int32, ParamArray array As System.Int32())) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1, New I ... r() {2, 3})')
-  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: P) (Syntax: 'M2')
-  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: x) (OperationKind.Argument) (Syntax: '1')
-      ILiteralExpression (Text: 1) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
-    IArgument (ArgumentKind.Explicit Matching Parameter: array) (OperationKind.Argument) (Syntax: 'New Integer() {2, 3}')
-      IArrayCreationExpression (Element Type: System.Int32) (OperationKind.ArrayCreationExpression, Type: System.Int32()) (Syntax: 'New Integer() {2, 3}')
-        Dimension Sizes(1): ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 2) (Syntax: 'New Integer() {2, 3}')
-        Initializer: IArrayInitializer (OperationKind.ArrayInitializer) (Syntax: '{2, 3}')
-            Element Values(2): ILiteralExpression (Text: 2) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 2) (Syntax: '2')
-              ILiteralExpression (Text: 3) (OperationKind.LiteralExpression, Type: System.Int32, Constant: 3) (Syntax: '3')
+IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(x)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(1): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: 'x')
+      ILocalReferenceExpression: x (OperationKind.LocalReferenceExpression, Type: System.Int32) (Syntax: 'x')
+]]>.Value
+
+            Dim expectedDiagnostics = String.Empty
+
+            VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
+        End Sub
+
+        <Fact()>
+        Public Sub NamedByRefModifiableArgumentsOutOfParameterOrder()
+            Dim source = <![CDATA[
+Class Program
+    Sub M1()
+        Dim x = 1
+        Dim y = 1.0
+        M2(b:=y, a:=x)'BIND:"M2(b:=y, a:=x)"
+    End Sub
+
+    Sub M2(ByRef Optional a As Integer = 0, ByRef Optional b As Double = 0.0)
+    End Sub
+End Class]]>.Value
+
+            Dim expectedOperationTree = <![CDATA[
+IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0], [ByRef b As System.Double = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(b:=y, a:=x)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(2): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: 'x')
+      ILocalReferenceExpression: x (OperationKind.LocalReferenceExpression, Type: System.Int32) (Syntax: 'x')
+    IArgument (ArgumentKind.Explicit Matching Parameter: b) (OperationKind.Argument) (Syntax: 'y')
+      ILocalReferenceExpression: y (OperationKind.LocalReferenceExpression, Type: System.Double) (Syntax: 'y')
+]]>.Value
+
+            Dim expectedDiagnostics = String.Empty
+
+            VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
+        End Sub
+
+        <Fact()>
+        Public Sub DefaultValueForByRefParameter()
+            Dim source = <![CDATA[
+Class Program
+    Sub M1()
+        Dim x = 1.0
+        M2()'BIND:"M2()"
+    End Sub
+
+    Sub M2(ByRef Optional a As Integer = 0)
+    End Sub
+End Class]]>.Value
+
+            Dim expectedOperationTree = <![CDATA[
+IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2()')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(1): IArgument (ArgumentKind.DefaultValue Matching Parameter: a) (OperationKind.Argument) (Syntax: 'M2')
+      ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: 'M2')
+]]>.Value
+
+            Dim expectedDiagnostics = String.Empty
+
+            VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
+        End Sub
+
+        <Fact()>
+        Public Sub PositionalByRefNonModifiableArgumentWithConversion()
+            Dim source = <![CDATA[
+Class Program
+    Sub M1()
+        M2(1.0)'BIND:"M2(1.0)"
+    End Sub
+
+    Sub M2(ByRef Optional a As Integer = 0)
+    End Sub
+End Class]]>.Value
+
+            Dim expectedOperationTree = <![CDATA[
+IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(1.0)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(1): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: '1.0')
+      IConversionExpression (ConversionKind.Basic, Implicit) (OperationKind.ConversionExpression, Type: System.Int32, Constant: 1) (Syntax: '1.0')
+        ILiteralExpression (OperationKind.LiteralExpression, Type: System.Double, Constant: 1) (Syntax: '1.0')
 ]]>.Value
 
             Dim expectedDiagnostics = String.Empty
@@ -174,6 +352,37 @@ IInvocationExpression ( Sub P.M2(x As System.Int32, ParamArray array As System.I
             VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
         End Sub
 
+        <Fact()>
+        Public Sub PositionalByRefModifiableArgumentWithConversion()
+            Dim source = <![CDATA[
+Class Program
+    Sub M1()
+        Dim x = 1.0
+        M2(x)'BIND:"M2(x)"
+    End Sub
+
+    Sub M2(ByRef Optional a As Integer = 0)
+    End Sub
+End Class]]>.Value
+
+            Dim expectedOperationTree = <![CDATA[
+IInvocationExpression ( Sub Program.M2([ByRef a As System.Int32 = 0])) (OperationKind.InvocationExpression, Type: System.Void) (Syntax: 'M2(x)')
+  Instance Receiver: IInstanceReferenceExpression (InstanceReferenceKind.Implicit) (OperationKind.InstanceReferenceExpression, Type: Program) (Syntax: 'M2')
+  Arguments(1): IArgument (ArgumentKind.Explicit Matching Parameter: a) (OperationKind.Argument) (Syntax: 'x')
+      ILocalReferenceExpression: x (OperationKind.LocalReferenceExpression, Type: System.Double) (Syntax: 'x')
+      InConversion: IConversionExpression (ConversionKind.Basic, Implicit) (OperationKind.ConversionExpression, Type: System.Int32) (Syntax: 'x')
+          IOperation:  (OperationKind.None) (Syntax: 'x')
+      OutConversion: IConversionExpression (ConversionKind.Basic, Implicit) (OperationKind.ConversionExpression, Type: System.Double) (Syntax: 'x')
+          IPlaceholderExpression (OperationKind.PlaceholderExpression, Type: System.Int32) (Syntax: 'x')
+]]>.Value
+
+            Dim expectedDiagnostics = String.Empty
+
+            VerifyOperationTreeAndDiagnosticsForTest(Of InvocationExpressionSyntax)(source, expectedOperationTree, expectedDiagnostics)
+        End Sub
+
+
+
     End Class
 End Namespace
 
-- 
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