|
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
#nullable disable
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.CodeFixes;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.RemoveUnnecessaryCast;
using Microsoft.CodeAnalysis.Diagnostics;
using Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.Diagnostics;
using Microsoft.CodeAnalysis.Test.Utilities;
using Roslyn.Test.Utilities;
using Xunit;
using Xunit.Abstractions;
namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.RemoveUnnecessaryCast
{
[Trait(Traits.Feature, Traits.Features.CodeActionsRemoveUnnecessaryCast)]
public partial class RemoveUnnecessaryCastTests_AsTests : AbstractCSharpDiagnosticProviderBasedUserDiagnosticTest
{
public RemoveUnnecessaryCastTests_AsTests(ITestOutputHelper logger)
: base(logger)
{
}
internal override (DiagnosticAnalyzer, CodeFixProvider) CreateDiagnosticProviderAndFixer(Workspace workspace)
=> (new CSharpRemoveUnnecessaryCastDiagnosticAnalyzer(), new CSharpRemoveUnnecessaryCastCodeFixProvider());
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545979")]
public async Task DontRemoveCastToErrorType()
{
await TestMissingInRegularAndScriptAsync(
"""
class Program
{
static void Main()
{
object s = ";
foreach (object x in ([|s as ErrorType|]))
{
}
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545146")]
public async Task ParenthesizeToKeepParseTheSame2()
{
await TestInRegularAndScriptAsync(
"""
using System;
class C
{
static void Main()
{
Action a = Console.WriteLine;
([|a as Action|])();
}
}
""",
"""
using System;
class C
{
static void Main()
{
Action a = Console.WriteLine;
a();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545138")]
public async Task DontRemoveTypeParameterCastToObject()
{
await TestMissingInRegularAndScriptAsync(
"""
class С
{
void Goo<T>(T obj)
{
int x = (int)([|obj as object|]);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545139")]
public async Task DontRemoveCastInIsTest()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class С
{
static void Main()
{
DayOfWeek[] a = {
};
Console.WriteLine([|a as object|] is int[]);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545142")]
public async Task DontRemoveCastNeedForUserDefinedOperator()
{
await TestMissingInRegularAndScriptAsync(
"""
class A
{
public static implicit operator A(string x)
{
return new A();
}
}
class Program
{
static void Main()
{
A x = [|null as string|];
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545143")]
public async Task DontRemovePointerCast1()
{
await TestMissingInRegularAndScriptAsync(
"""
unsafe class C
{
static unsafe void Main()
{
var x = (int)([|null as int*|]);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545144")]
public async Task DontRemoveCastToObjectFromDelegateComparison()
{
// The cast below can't be removed because it would result in the Delegate
// op_Equality operator overload being used over reference equality.
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
Action a = Console.WriteLine;
Action b = Console.WriteLine;
Console.WriteLine(a == ([|b as object|]));
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545145")]
public async Task DontRemoveCastToAnonymousMethodWhenOnLeftOfAsCast()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class C
{
static void Main()
{
var x = [|delegate {
} as Action|]
as Action;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545157")]
public async Task DontRemoveIdentityCastWhichAffectsOverloadResolution1()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
Goo(x => [|x as string|]);
}
static void Goo(Func<int, object> x)
{
}
static void Goo(Func<string, object> x)
{
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545158")]
public async Task DontRemoveIdentityCastWhichAffectsOverloadResolution2()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
var x = [|1 as IComparable<int>|];
Goo(x);
}
static void Goo(IComparable<int> x)
{
}
static void Goo(int x)
{
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545158")]
public async Task DontRemoveIdentityCastWhichAffectsOverloadResolution3()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
var x = [|1 as IComparable<int>|];
var y = x;
Goo(y);
}
static void Goo(IComparable<int> x)
{
}
static void Goo(int x)
{
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545747")]
public async Task DontRemoveCastWhichChangesTypeOfInferredLocal()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
static void Main()
{
var x = [|"" as object|];
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545159")]
public async Task DontRemoveNeededCastToIListOfObject()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
using System.Collections.Generic;
class C
{
static void Main()
{
Action<object>[] x = {
};
Goo(x);
}
static void Goo<T>(Action<T>[] x)
{
var y = (IList<Action<object>>)([|x as IList<object>|]);
Console.WriteLine(y.Count);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545287"), WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/880752")]
public async Task RemoveUnneededCastInParameterDefaultValue()
{
await TestInRegularAndScriptAsync(
"""
class Program
{
static void M1(string i1 = [|null as string|])
{
}
}
""",
"""
class Program
{
static void M1(string i1 = null)
{
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545289")]
public async Task RemoveUnneededCastInReturnStatement()
{
await TestInRegularAndScriptAsync(
"""
class Program
{
static string M2()
{
return [|"" as string|];
}
}
""",
"""
class Program
{
static string M2()
{
return "";
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545288")]
public async Task RemoveUnneededCastInLambda1()
{
await TestInRegularAndScriptAsync(
"""
using System;
class Program
{
static void M1()
{
Func<string> f1 = () => [|"" as string|];
}
}
""",
"""
using System;
class Program
{
static void M1()
{
Func<string> f1 = () => "";
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545288")]
public async Task RemoveUnneededCastInLambda2()
{
await TestInRegularAndScriptAsync(
"""
using System;
class Program
{
static void M1()
{
Func<string> f1 = () => { return [|"" as string|]; };
}
}
""",
"""
using System;
class Program
{
static void M1()
{
Func<string> f1 = () => { return ""; };
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545288")]
public async Task RemoveUnneededCastInLambda3()
{
await TestInRegularAndScriptAsync(
"""
using System;
class Program
{
static void M1()
{
Func<string> f1 = _ => { return [|"" as string|]; };
}
}
""",
"""
using System;
class Program
{
static void M1()
{
Func<string> f1 = _ => { return ""; };
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545288")]
public async Task RemoveUnneededCastInLambda4()
{
await TestInRegularAndScriptAsync(
"""
using System;
class Program
{
static void M1()
{
Func<string> f1 = _ => [|"" as string|];
}
}
""",
"""
using System;
class Program
{
static void M1()
{
Func<string> f1 = _ => "";
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545291")]
public async Task RemoveUnneededCastInConditionalExpression1()
{
await TestInRegularAndScriptAsync(
"""
class Test
{
public static void Main()
{
int b = 5;
string f1 = (b == 5) ? [|"a" as string|] : "b" as string;
}
}
""",
"""
class Test
{
public static void Main()
{
int b = 5;
string f1 = (b == 5) ? "a" : "b" as string;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545291")]
public async Task RemoveUnneededCastInConditionalExpression2()
{
await TestInRegularAndScriptAsync(
"""
class Test
{
public static void Main()
{
int b = 5;
string f1 = (b == 5) ? "a" as string : [|"b" as string|];
}
}
""",
"""
class Test
{
public static void Main()
{
int b = 5;
string f1 = (b == 5) ? "a" as string : "b";
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545291")]
public async Task DontRemoveNeededCastInConditionalExpression()
{
await TestMissingInRegularAndScriptAsync(
"""
class Test
{
public static void Main()
{
int b = 5;
var f1 = (b == 5) ? "" : [|"" as object|];
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545459")]
public async Task DoNotRemoveIllegalAsCastInsideADelegateConstructor()
{
await TestMissingAsync(
"""
using System;
class Test
{
delegate void D(int x);
static void Main(string[] args)
{
var cd1 = new D([|M1 as Action<int>|]);
}
public static void M1(int i) { }
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545422")]
public async Task RemoveUnneededCastInsideCaseLabel()
{
await TestInRegularAndScriptAsync(
"""
class Test
{
static void Main()
{
switch ("")
{
case [|"" as string|]:
break;
}
}
}
""",
"""
class Test
{
static void Main()
{
switch ("")
{
case "":
break;
}
}
}
""");
}
[WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545595")]
[WpfFact(Skip = "529787")]
public async Task RemoveUnneededCastInCollectionInitializer()
{
await TestInRegularAndScriptAsync(
"""
using System.Collections.Generic;
class Program
{
static void Main()
{
var z = new List<string> { [|"" as string|] };
}
}
""",
"""
using System.Collections.Generic;
class Program
{
static void Main()
{
var z = new List<string> { "" };
}
}
""");
}
[WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529787")]
[WpfFact(Skip = "529787")]
public async Task DontRemoveNecessaryCastWhichInCollectionInitializer1()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
using System.Collections.Generic;
class X : List<int>
{
void Add(object x)
{
Console.WriteLine(1);
}
void Add(string x)
{
Console.WriteLine(2);
}
static void Main()
{
var z = new X { [|"" as object|] };
}
}
""");
}
[WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529787")]
[WpfFact(Skip = "529787")]
public async Task DontRemoveNecessaryCastWhichInCollectionInitializer2()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
using System.Collections.Generic;
class X : List<int>
{
void Add(object x)
{
Console.WriteLine(1);
}
void Add(string x)
{
Console.WriteLine(2);
}
static void Main()
{
X z = new X { [|"" as object|] };
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545607")]
public async Task RemoveUnneededCastInArrayInitializer()
{
await TestInRegularAndScriptAsync(
"""
class X
{
static void Goo()
{
string x = ";
var s = new object[] { [|x as object|] };
}
}
""",
"""
class X
{
static void Goo()
{
string x = ";
var s = new object[] { x };
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545608")]
public async Task DontRemoveNecessaryCastWithImplicitUserDefinedConversion()
{
await TestMissingInRegularAndScriptAsync(
"""
class X
{
static void Goo()
{
X x = null;
object y = [|x as string|];
}
public static implicit operator string(X x)
{
return ";
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545941")]
public async Task DontRemoveNecessaryCastWithImplicitConversionInThrow()
{
// The cast below can't be removed because the throw statement expects
// an expression of type Exception -- not an expression convertible to
// Exception.
await TestMissingInRegularAndScriptAsync(
"""
using System;
class E
{
public static implicit operator Exception(E e)
{
return new Exception();
}
static void Main()
{
throw [|new E() as Exception|];
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545981")]
public async Task DontRemoveNecessaryCastInThrow()
{
// The cast below can't be removed because the throw statement expects
// an expression of type Exception -- not an expression convertible to
// Exception.
await TestMissingInRegularAndScriptAsync(
"""
using System;
class C
{
static void Main()
{
object ex = new Exception();
throw [|ex as Exception|];
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545941")]
public async Task RemoveUnnecessaryCastInThrow()
{
await TestInRegularAndScriptAsync(
"""
using System;
class E
{
static void Main()
{
throw [|new Exception() as Exception|];
}
}
""",
"""
using System;
class E
{
static void Main()
{
throw new Exception();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545945")]
public async Task DontRemoveNecessaryDowncast()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
void Goo(object y)
{
var x = [|y as string|];
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545606")]
public async Task DontRemoveNecessaryCastFromNullToTypeParameter()
{
await TestMissingInRegularAndScriptAsync(
"""
class X
{
static void Goo<T, S>() where T : class, S
{
S y = [|null as T|];
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545744")]
public async Task DontRemoveNecessaryCastInImplicitlyTypedArray()
{
await TestMissingInRegularAndScriptAsync(
"""
class X
{
static void Goo()
{
string x = ";
var s = new[] { [|x as object|] };
s[0] = 1;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545750")]
public async Task RemoveUnnecessaryCastToBaseType()
{
await TestInRegularAndScriptAsync(
"""
class X
{
static void Main()
{
var s = ([|new X() as object|]).ToString();
}
public override string ToString()
{
return ";
}
}
""",
"""
class X
{
static void Main()
{
var s = new X().ToString();
}
public override string ToString()
{
return ";
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545855")]
public async Task DoRemoveIllegalAsCastOnLambda()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
using System.Collections.Generic;
using System.Reflection;
static class Program
{
static void Main()
{
FieldInfo[] fields = typeof(Exception).GetFields();
Console.WriteLine(fields.Any([|(field => field.IsStatic) as Func<FieldInfo, bool>|]));
}
static bool Any<T>(this IEnumerable<T> s, Func<T, bool> predicate)
{
return false;
}
static bool Any<T>(this ICollection<T> s, Func<T, bool> predicate)
{
return true;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529816")]
public async Task RemoveUnnecessaryCastInQueryExpression()
{
await TestInRegularAndScriptAsync(
"""
using System;
class A
{
int Select(Func<int, string> x) { return 1; }
static void Main()
{
Console.WriteLine(from y in new A() select [|"" as string|]);
}
}
""",
"""
using System;
class A
{
int Select(Func<int, string> x) { return 1; }
static void Main()
{
Console.WriteLine(from y in new A() select "");
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529816")]
public async Task DontRemoveNecessaryCastInQueryExpression()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class A
{
int Select(Func<int, string> x)
{
return 1;
}
int Select(Func<int, object> x)
{
return 2;
}
static void Main()
{
Console.WriteLine(from y in new A()
select [|"" as object|]);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529831")]
public async Task DontRemoveNecessaryCastFromTypeParameterToInterface()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
interface IIncrementable
{
int Value { get; }
void Increment();
}
struct S : IIncrementable
{
public int Value { get; private set; }
public void Increment()
{
Value++;
}
}
class C : IIncrementable
{
public int Value { get; private set; }
public void Increment()
{
Value++;
}
}
static class Program
{
static void Main()
{
Goo(new S(), new C());
}
static void Goo<TAny, TClass>(TAny x, TClass y)
where TAny : IIncrementable
where TClass : class, IIncrementable
{
([|x as IIncrementable|]).Increment(); // False Unnecessary Cast
((IIncrementable)y).Increment(); // Unnecessary Cast - OK
Console.WriteLine(x.Value);
Console.WriteLine(y.Value);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529831")]
public async Task RemoveUnnecessaryCastFromTypeParameterToInterface()
{
await TestInRegularAndScriptAsync(
"""
using System;
interface IIncrementable
{
int Value { get; }
void Increment();
}
struct S : IIncrementable
{
public int Value { get; private set; }
public void Increment() { Value++; }
}
class C: IIncrementable
{
public int Value { get; private set; }
public void Increment() { Value++; }
}
static class Program
{
static void Main()
{
Goo(new S(), new C());
}
static void Goo<TAny, TClass>(TAny x, TClass y)
where TAny : IIncrementable
where TClass : class, IIncrementable
{
((IIncrementable)x).Increment(); // False Unnecessary Cast
([|y as IIncrementable|]).Increment(); // Unnecessary Cast - OK
Console.WriteLine(x.Value);
Console.WriteLine(y.Value);
}
}
""",
"""
using System;
interface IIncrementable
{
int Value { get; }
void Increment();
}
struct S : IIncrementable
{
public int Value { get; private set; }
public void Increment() { Value++; }
}
class C: IIncrementable
{
public int Value { get; private set; }
public void Increment() { Value++; }
}
static class Program
{
static void Main()
{
Goo(new S(), new C());
}
static void Goo<TAny, TClass>(TAny x, TClass y)
where TAny : IIncrementable
where TClass : class, IIncrementable
{
((IIncrementable)x).Increment(); // False Unnecessary Cast
y.Increment(); // Unnecessary Cast - OK
Console.WriteLine(x.Value);
Console.WriteLine(y.Value);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545877")]
public async Task DontCrashOnIncompleteMethodDeclaration()
{
await TestInRegularAndScriptAsync(
"""
using System;
class A
{
static void Main()
{
string
Goo(x => 1, [|"" as string|]);
}
static void Goo<T, S>(T x, )
{
}
}
""",
"""
using System;
class A
{
static void Main()
{
string
Goo(x => 1, "");
}
static void Goo<T, S>(T x, )
{
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529791")]
public async Task RemoveUnnecessaryCastToNullable1()
{
await TestInRegularAndScriptAsync(
"""
class X
{
static void Goo()
{
object x = (string)null;
object y = [|null as int?|];
}
}
""",
"""
class X
{
static void Goo()
{
object x = (string)null;
object y = null;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545850")]
public async Task RemoveSurroundingParentheses()
{
await TestInRegularAndScriptAsync(
"""
class Program
{
static void Main()
{
string x = "";
([|x as string|]).ToString();
}
}
""",
"""
class Program
{
static void Main()
{
string x = "";
x.ToString();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529846")]
public async Task DontRemoveNecessaryCastFromTypeParameterToObject()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
static void Goo<T>(T x, object y)
{
if (([|x as object|]) == y)
{
}
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545858")]
public async Task DontRemoveNecessaryCastFromDelegateTypeToMulticastDelegate()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class C
{
static void Main()
{
Action x = Console.WriteLine;
Action y = Console.WriteLine;
Console.WriteLine(([|x as MulticastDelegate|]) == y);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529842")]
public async Task DontRemoveNecessaryCastInTernaryExpression()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class X
{
public static implicit operator string(X x)
{
return x.ToString();
}
static void Main()
{
bool b = true;
X x = new X();
Console.WriteLine(b ? [|null as string|] : x);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545882"), WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/880752")]
public async Task RemoveCastInConstructorInitializer1()
{
await TestInRegularAndScriptAsync(
"""
class C
{
C(string x) { }
C() : this([|"" as string|]) { }
}
""",
"""
class C
{
C(string x) { }
C() : this("") { }
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545958"), WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/880752")]
public async Task RemoveCastInConstructorInitializer2()
{
await TestInRegularAndScriptAsync(
"""
using System.Collections;
class C
{
C(int x) { }
C(object x) { }
C() : this([|"" as IEnumerable|]) { }
}
""",
"""
using System.Collections;
class C
{
C(int x) { }
C(object x) { }
C() : this("") { }
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545957")]
public async Task DontRemoveCastInConstructorInitializer3()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
C(string x)
{
}
C() : this([|"" as object|])
{
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545842")]
public async Task RemoveCastToNullableInArithmeticExpression()
{
await TestInRegularAndScriptAsync(
"""
static class C
{
static void Main()
{
int? x = 1;
long y = 2;
long? z = x + ([|y as long?|]);
}
}
""",
"""
static class C
{
static void Main()
{
int? x = 1;
long y = 2;
long? z = x + y;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545942")]
public async Task DoNotRemoveCastFromStringTypeToObjectInReferenceEquality()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
object x = "";
Console.WriteLine(x == ([|"" as object|]));
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545962")]
public async Task DontRemoveCastWhenExpressionDoesntBind()
{
// Note: The cast below can't be removed because its expression doesn't bind.
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
([|x as IDisposable|]).Dispose();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545944")]
public async Task DontRemoveNecessaryCastBeforePointerDereference1()
{
// Note: The cast below can't be removed because it would result in *null,
// which is illegal.
await TestMissingInRegularAndScriptAsync(
"""
unsafe class C
{
int x = *([|null as int*|]);
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545978")]
public async Task DontRemoveNecessaryCastBeforePointerDereference2()
{
// Note: The cast below can't be removed because it would result in dereferencing
// void*, which is illegal.
await TestMissingInRegularAndScriptAsync(
"""
unsafe class C
{
static void Main()
{
void* p = null;
int x = *([|p as int*|]);
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/26640")]
public async Task DontRemoveCastToByteFromIntInConditionalExpression_CSharp8()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
object M1(bool b)
{
return [|b ? (1 as byte?) : (0 as byte?)|];
}
}
""", new TestParameters(parseOptions: CSharpParseOptions.Default.WithLanguageVersion(LanguageVersion.CSharp8)));
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/26640")]
public async Task DontRemoveCastToByteFromIntInConditionalExpression_CSharp9()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
object M1(bool b)
{
return [|b ? (1 as byte?) : (0 as byte?)|];
}
}
""", new TestParameters(parseOptions: CSharpParseOptions.Default.WithLanguageVersion(LanguageVersion.CSharp9)));
}
#region Interface Casts
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545889")]
public async Task DontRemoveCastToInterfaceForUnsealedType()
{
// Note: The cast below can't be removed because X is not sealed.
await TestMissingInRegularAndScriptAsync(
"""
using System;
class X : IDisposable
{
static void Main()
{
X x = new Y();
([|x as IDisposable|]).Dispose();
}
public void Dispose()
{
Console.WriteLine("X.Dispose");
}
}
class Y : X, IDisposable
{
void IDisposable.Dispose()
{
Console.WriteLine("Y.Dispose");
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545890")]
public async Task DoRemoveCastToInterfaceForSealedType1()
{
await TestInRegularAndScriptAsync(
"""
using System;
interface I
{
void Goo(int x = 0);
}
sealed class C : I
{
public void Goo(int x = 0)
{
Console.WriteLine(x);
}
static void Main()
{
([|new C() as I|]).Goo();
}
}
""",
"""
using System;
interface I
{
void Goo(int x = 0);
}
sealed class C : I
{
public void Goo(int x = 0)
{
Console.WriteLine(x);
}
static void Main()
{
new C().Goo();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545890")]
public async Task DoRemoveCastToInterfaceForSealedType2()
{
await TestInRegularAndScriptAsync(
"""
using System;
interface I
{
string Goo { get; }
}
sealed class C : I
{
public string Goo
{
get
{
return "Nikov Rules";
}
}
static void Main()
{
Console.WriteLine(([|new C() as I|]).Goo);
}
}
""",
"""
using System;
interface I
{
string Goo { get; }
}
sealed class C : I
{
public string Goo
{
get
{
return "Nikov Rules";
}
}
static void Main()
{
Console.WriteLine(new C().Goo);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545890")]
public async Task DoNotRemoveCastToInterfaceForSealedType3()
{
await TestMissingAsync(
"""
using System;
interface I
{
string Goo { get; }
}
sealed class C : I
{
public C Instance { get { return new C(); } }
public string Goo
{
get
{
return "Nikov Rules";
}
}
static void Main()
{
Console.WriteLine(([|Instance as I|]).Goo);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545890")]
public async Task DontRemoveCastToInterfaceForSealedType4()
{
// Note: The cast below can't be removed (even though C is sealed)
// because the unspecified optional parameter default values differ.
await TestMissingInRegularAndScriptAsync(
"""
using System;
interface I
{
void Goo(int x = 0);
}
sealed class C : I
{
public void Goo(int x = 1)
{
Console.WriteLine(x);
}
static void Main()
{
([|new C() as I|]).Goo();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545890")]
public async Task DoRemoveCastToInterfaceForSealedTypeWhenDefaultValuesAreDifferentButParameterIsPassed()
{
await TestInRegularAndScriptAsync(
"""
using System;
interface I
{
void Goo(int x = 0);
}
sealed class C : I
{
public void Goo(int x = 1)
{
Console.WriteLine(x);
}
static void Main()
{
([|new C() as I|]).Goo(2);
}
}
""",
"""
using System;
interface I
{
void Goo(int x = 0);
}
sealed class C : I
{
public void Goo(int x = 1)
{
Console.WriteLine(x);
}
static void Main()
{
new C().Goo(2);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545888")]
public async Task DontRemoveCastToInterfaceForSealedType6()
{
// Note: The cast below can't be removed (even though C is sealed)
// because the specified named arguments refer to parameters that
// appear at different positions in the member signatures.
await TestMissingInRegularAndScriptAsync(
"""
using System;
interface I
{
void Goo(int x = 0, int y = 0);
}
sealed class C : I
{
public void Goo(int y = 0, int x = 0)
{
Console.WriteLine(x);
}
static void Main()
{
([|new C() as I|]).Goo(x: 1);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545888")]
public async Task DoNotRemoveCastToInterfaceForSealedType7()
{
await TestMissingAsync(
"""
using System;
interface I
{
int this[int x = 0, int y = 0] { get; }
}
sealed class C : I
{
public int this[int x = 0, int y = 0]
{
get
{
return x * 2;
}
}
static void Main()
{
Console.WriteLine(([|new C() as I|])[x: 1]);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545888")]
public async Task DontRemoveCastToInterfaceForSealedType8()
{
// Note: The cast below can't be removed (even though C is sealed)
// because the specified named arguments refer to parameters that
// appear at different positions in the member signatures.
await TestMissingInRegularAndScriptAsync(
"""
using System;
interface I
{
int this[int x = 0, int y = 0] { get; }
}
sealed class C : I
{
public int this(int y = 0, int x = 0)
{
get
{
return x * 2;
}
}
static void Main()
{
Console.WriteLine(([|new C() as I|])[x: 1]);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545883")]
public async Task DontRemoveCastToInterfaceForSealedType9()
{
// Note: The cast below can't be removed (even though C is sealed)
// because it would result in binding to a Dispose method that doesn't
// implement IDisposable.Dispose().
await TestMissingInRegularAndScriptAsync(
"""
using System;
using System.IO;
sealed class C : MemoryStream
{
static void Main()
{
C s = new C();
([|s as IDisposable|]).Dispose();
}
new public void Dispose()
{
Console.WriteLine("new Dispose()");
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545887")]
public async Task DontRemoveCastToInterfaceForStruct1()
{
// Note: The cast below can't be removed because the cast boxes 's' and
// unboxing would change program behavior.
await TestMissingInRegularAndScriptAsync(
"""
using System;
interface IIncrementable
{
int Value { get; }
void Increment();
}
struct S : IIncrementable
{
public int Value { get; private set; }
public void Increment()
{
Value++;
}
static void Main()
{
var s = new S();
([|s as IIncrementable|]).Increment();
Console.WriteLine(s.Value);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545834")]
public async Task RemoveCastToInterfaceForStruct2()
{
// Note: The cast below can be removed because we are sure to have
// a fresh copy of the struct from the GetEnumerator() method.
await TestInRegularAndScriptAsync(
"""
using System;
using System.Collections.Generic;
class Program
{
static void Main()
{
([|GetEnumerator() as IDisposable|]).Dispose();
}
static List<int>.Enumerator GetEnumerator()
{
var x = new List<int> { 1, 2, 3 };
return x.GetEnumerator();
}
}
""",
"""
using System;
using System.Collections.Generic;
class Program
{
static void Main()
{
GetEnumerator().Dispose();
}
static List<int>.Enumerator GetEnumerator()
{
var x = new List<int> { 1, 2, 3 };
return x.GetEnumerator();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/544655")]
public async Task RemoveCastToICloneableForDelegate()
{
// Note: The cast below can be removed because delegates are implicitly
// sealed.
await TestInRegularAndScriptAsync(
"""
using System;
class C
{
static void Main()
{
Action a = () => { };
var c = ([|a as ICloneable|]).Clone();
}
}
""",
"""
using System;
class C
{
static void Main()
{
Action a = () => { };
var c = a.Clone();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545926")]
public async Task RemoveCastToICloneableForArray()
{
// Note: The cast below can be removed because arrays are implicitly
// sealed.
await TestInRegularAndScriptAsync(
"""
using System;
class C
{
static void Main()
{
var a = new[] { 1, 2, 3 };
var c = ([|a as ICloneable|]).Clone();
}
}
""",
"""
using System;
class C
{
static void Main()
{
var a = new[] { 1, 2, 3 };
var c = a.Clone();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529897")]
public async Task RemoveCastToIConvertibleForEnum()
{
// Note: The cast below can be removed because enums are implicitly
// sealed.
await TestInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
Enum e = DayOfWeek.Monday;
var y = ([|e as IConvertible|]).GetTypeCode();
}
}
""",
"""
using System;
class Program
{
static void Main()
{
Enum e = DayOfWeek.Monday;
var y = e.GetTypeCode();
}
}
""");
}
#endregion
#region ParamArray Parameter Casts
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545141")]
public async Task DontRemoveCastToObjectInParamArrayArg1()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class C
{
static void Main()
{
Goo([|null as object|]);
}
static void Goo(params object[] x)
{
Console.WriteLine(x.Length);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529911")]
public async Task DontRemoveCastToIntArrayInParamArrayArg2()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class C
{
static void Main()
{
Goo([|null as int[]|]);
}
static void Goo(params object[] x)
{
Console.WriteLine(x.Length);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529911")]
public async Task DontRemoveCastToObjectArrayInParamArrayArg3()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class C
{
static void Main()
{
Goo([|null as object[]|]);
}
static void Goo(params object[][] x)
{
Console.WriteLine(x.Length);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529911")]
public async Task RemoveCastToObjectArrayInParamArrayArg1()
{
await TestInRegularAndScriptAsync(
"""
class C
{
static void Goo(params object[] x) { }
static void Main()
{
Goo([|null as object[]|]);
}
}
""",
"""
class C
{
static void Goo(params object[] x) { }
static void Main()
{
Goo(null);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529911")]
public async Task RemoveCastToStringArrayInParamArrayArg2()
{
await TestInRegularAndScriptAsync(
"""
class C
{
static void Goo(params object[] x) { }
static void Main()
{
Goo([|null as string[]|]);
}
}
""",
"""
class C
{
static void Goo(params object[] x) { }
static void Main()
{
Goo(null);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529911")]
public async Task RemoveCastToIntArrayInParamArrayArg3()
{
await TestInRegularAndScriptAsync(
"""
class C
{
static void Goo(params int[] x) { }
static void Main()
{
Goo([|null as int[]|]);
}
}
""",
"""
class C
{
static void Goo(params int[] x) { }
static void Main()
{
Goo(null);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529911")]
public async Task RemoveCastToObjectArrayInParamArrayArg4()
{
await TestInRegularAndScriptAsync(
"""
class C
{
static void Goo(params object[] x) { }
static void Main()
{
Goo([|null as object[]|], null);
}
}
""",
"""
class C
{
static void Goo(params object[] x) { }
static void Main()
{
Goo(null, null);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529911")]
public async Task RemoveCastToObjectInParamArrayArg5()
{
await TestInRegularAndScriptAsync(
"""
class C
{
static void Goo(params object[] x) { }
static void Main()
{
Goo([|null as object|], null);
}
}
""",
"""
class C
{
static void Goo(params object[] x) { }
static void Main()
{
Goo(null, null);
}
}
""");
}
[Fact]
public async Task RemoveCastToObjectArrayInParamArrayWithNamedArgument()
{
await TestInRegularAndScriptAsync(
"""
class C
{
static void Main()
{
Goo(x: [|null as object[]|]);
}
static void Goo(params object[] x) { }
}
""",
"""
class C
{
static void Main()
{
Goo(x: null);
}
static void Goo(params object[] x) { }
}
""");
}
#endregion
#region ForEach Statements
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545961")]
public async Task DontRemoveNecessaryCastInForEach1()
{
// The cast below can't be removed because it would result an error
// in the foreach statement.
await TestMissingInRegularAndScriptAsync(
"""
using System.Collections;
class Program
{
static void Main()
{
object s = ";
foreach (object x in [|s as IEnumerable|])
{
}
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545961")]
public async Task DontRemoveNecessaryCastInForEach2()
{
// The cast below can't be removed because it would result an error
// in the foreach statement.
await TestMissingInRegularAndScriptAsync(
"""
using System.Collections.Generic;
class Program
{
static void Main()
{
object s = ";
foreach (object x in [|s as IEnumerable<char>|])
{
}
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545961")]
public async Task DontRemoveNecessaryCastInForEach3()
{
// The cast below can't be removed because it would result an error
// in the foreach statement since C doesn't contain a GetEnumerator()
// method.
await TestMissingInRegularAndScriptAsync(
"""
using System.Collections;
class D
{
public IEnumerator GetEnumerator()
{
yield return 1;
}
}
class C
{
public static implicit operator D(C c)
{
return new D();
}
static void Main()
{
object s = ";
foreach (object x in [|new C() as D|])
{
}
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545961")]
public async Task DontRemoveNecessaryCastInForEach4()
{
// The cast below can't be removed because it would result in
// C.GetEnumerator() being called rather than D.GetEnumerator().
await TestMissingInRegularAndScriptAsync(
"""
using System;
using System.Collections;
class D
{
public IEnumerator GetEnumerator()
{
yield return 1;
}
}
class C
{
public IEnumerator GetEnumerator()
{
yield return 2;
}
public static implicit operator D(C c)
{
return new D();
}
static void Main()
{
object s = ";
foreach (object x in [|new C() as D|])
{
Console.WriteLine(x);
}
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545961")]
public async Task DontRemoveNecessaryCastInForEach5()
{
// The cast below can't be removed because it would change the
// type of 'x'.
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
string[] s = {
"A"
};
foreach (var x in [|s as Array|])
{
var y = x;
y = 1;
}
}
}
""");
}
#endregion
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545925")]
public async Task DontRemoveCastIfOverriddenMethodHasIncompatibleParameterList()
{
// Note: The cast below can't be removed because the parameter list
// of Goo and its override have different default values.
await TestMissingInRegularAndScriptAsync(
"""
using System;
abstract class Y
{
public abstract void Goo(int x = 1);
}
class X : Y
{
static void Main()
{
([|new X() as Y|]).Goo();
}
public override void Goo(int x = 2)
{
Console.WriteLine(x);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545925")]
public async Task RemoveCastIfOverriddenMethodHaveCompatibleParameterList()
{
// Note: The cast below can be removed because the parameter list
// of Goo and its override have the same default values.
await TestInRegularAndScriptAsync(
"""
using System;
abstract class Y
{
public abstract void Goo(int x = 1);
}
class X : Y
{
static void Main()
{
([|new X() as Y|]).Goo();
}
public override void Goo(int x = 1)
{
Console.WriteLine(x);
}
}
""",
"""
using System;
abstract class Y
{
public abstract void Goo(int x = 1);
}
class X : Y
{
static void Main()
{
new X().Goo();
}
public override void Goo(int x = 1)
{
Console.WriteLine(x);
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529916")]
public async Task RemoveCastInReceiverForMethodGroup()
{
// Note: The cast below can be removed because the it results in
// the same method group.
await TestInRegularAndScriptAsync(
"""
using System;
static class Program
{
static void Main()
{
Action a = ([|"" as string|]).Goo;
}
static void Goo(this string x) { }
}
""",
"""
using System;
static class Program
{
static void Main()
{
Action a = "".Goo;
}
static void Goo(this string x) { }
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/609497")]
public async Task Bugfix_609497()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
using System.Threading.Tasks;
class Program
{
static void Main()
{
Goo().Wait();
}
static async Task Goo()
{
Task task = Task.FromResult(0);
Console.WriteLine(await ([|task as dynamic|]));
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/624252")]
[WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/608180")]
public async Task DontRemoveCastIfArgumentIsRestricted_TypedReference()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main(string[] args)
{
}
static void v(dynamic x)
{
var y = default(TypedReference);
dd([|x as object|], y);
}
static void dd(object obj, TypedReference d)
{
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/627107")]
public async Task DontRemoveCastOnArgumentsWithOtherDynamicArguments()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
C<string>.InvokeGoo(0);
}
}
class C<T>
{
public static void InvokeGoo(dynamic x)
{
Console.WriteLine(Goo(x, [|"" as object|], ""));
}
static void Goo(int x, string y, T z)
{
}
static bool Goo(int x, object y, object z)
{
return true;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/627107")]
public async Task DontRemoveCastOnArgumentsWithOtherDynamicArguments_Bracketed()
{
await TestMissingInRegularAndScriptAsync(
"""
class C<T>
{
int this[int x, T s, string d = "abc"]
{
get
{
return 0;
}
set
{
}
}
int this[int x, object s, object d]
{
get
{
return 0;
}
set
{
}
}
void Goo(dynamic xx)
{
var y = this[x: xx, s: "", d: [|"" as object|]];
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/627107")]
public async Task DontRemoveCastOnArgumentsWithDynamicReceiverOpt()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
static bool Goo(dynamic d)
{
d([|"" as object|]);
return true;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/627107")]
public async Task DontRemoveCastOnArgumentsWithDynamicReceiverOpt_1()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
static bool Goo(dynamic d)
{
d.goo([|"" as object|]);
return true;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/627107")]
public async Task DontRemoveCastOnArgumentsWithDynamicReceiverOpt_2()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
static bool Goo(dynamic d)
{
d.goo.bar.goo([|"" as object|]);
return true;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/627107")]
public async Task DontRemoveCastOnArgumentsWithDynamicReceiverOpt_3()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
static bool Goo(dynamic d)
{
d.goo().bar().goo([|"" as object|]);
return true;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/627107")]
public async Task DontRemoveCastOnArgumentsWithOtherDynamicArguments_1()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
static void Main()
{
C<string>.InvokeGoo(0);
}
}
class C<T>
{
public static void InvokeGoo(dynamic x)
{
Console.WriteLine(Goo([|"" as object|], x, ""));
}
static void Goo(string y, int x, T z)
{
}
static bool Goo(object y, int x, object z)
{
return true;
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/529846")]
public async Task DontUnnecessaryCastFromTypeParameterToObject()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
static void Goo<T>(T x, object y)
{
if (([|x as object|]) == y)
{
}
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/640136")]
public async Task RemoveUnnecessaryCastAndParseCorrect()
{
await TestInRegularAndScriptAsync(
"""
using System;
using System.Threading.Tasks;
class C
{
void Goo(Task<Action> x)
{
(([|x as Task<Action>|]).Result)();
}
}
""",
"""
using System;
using System.Threading.Tasks;
class C
{
void Goo(Task<Action> x)
{
(x.Result)();
}
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/626026")]
public async Task DontRemoveCastIfUserDefinedExplicitCast()
{
await TestMissingInRegularAndScriptAsync(
"""
class Program
{
static void Main(string[] args)
{
B bar = new B();
A a = [|bar as A|];
}
}
public class A
{
public static explicit operator A(B b)
{
return new A();
}
}
public struct B
{
}
""");
}
[Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/770187")]
public async Task DontRemoveNecessaryCastInSwitchExpression()
{
await TestMissingInRegularAndScriptAsync(
"""
namespace ConsoleApplication23
{
class Program
{
static void Main(string[] args)
{
int goo = 0;
switch ([|goo as E?|])
{
case E.A:
case E.B:
return;
}
}
}
enum E
{
A,
B,
C
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/2761")]
[WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/844482")]
public async Task DontRemoveCastFromBaseToDerivedWithExplicitReference()
{
await TestMissingInRegularAndScriptAsync(
"""
class Program
{
static void Main(string[] args)
{
C x = null;
C y = null;
y = [|x as D|];
}
}
class C
{
}
class D : C
{
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/3254")]
public async Task DontRemoveCastToTypeParameterWithExceptionConstraint()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
private static void RequiresCondition<TException>(bool condition, string messageOnFalseCondition) where TException : Exception
{
if (!condition)
{
throw [|Activator.CreateInstance(typeof(TException), messageOnFalseCondition) as TException|];
}
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/3254")]
public async Task DontRemoveCastToTypeParameterWithExceptionSubTypeConstraint()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class Program
{
private static void RequiresCondition<TException>(bool condition, string messageOnFalseCondition) where TException : ArgumentException
{
if (!condition)
{
throw [|Activator.CreateInstance(typeof(TException), messageOnFalseCondition) as TException|];
}
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/8111")]
public async Task DontRemoveCastThatChangesShapeOfAnonymousTypeObject()
{
await TestMissingInRegularAndScriptAsync(
"""
class Program
{
static void Main(object o)
{
object thing = new { shouldBeAString = [|o as string|] };
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/8111")]
public async Task RemoveCastThatDoesntChangeShapeOfAnonymousTypeObject()
{
await TestInRegularAndScriptAsync(
"""
class Program
{
static void Main(string o)
{
object thing = new { shouldBeAString = [|o as string|] };
}
}
""",
"""
class Program
{
static void Main(string o)
{
object thing = new { shouldBeAString = o };
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/18978")]
public async Task DontRemoveCastOnCallToMethodWithParamsArgs()
{
await TestMissingInRegularAndScriptAsync(
"""
class Program
{
public static void Main(string[] args)
{
var takesArgs = new[] { "Hello", "World" };
TakesParams([|takesArgs as object|]);
}
private static void TakesParams(params object[] goo)
{
Console.WriteLine(goo.Length);
}
}
""");
}
[Fact]
public async Task DoRemoveCastOnCallToMethodWithIncorrectParamsArgs()
{
await TestInRegularAndScript1Async(
"""
class Program
{
public static void Main(string[] args)
{
TakesParams([|null as string|]);
}
private static void TakesParams(params string wrongDefined)
{
Console.WriteLine(wrongDefined.Length);
}
}
""",
"""
class Program
{
public static void Main(string[] args)
{
TakesParams(null);
}
private static void TakesParams(params string wrongDefined)
{
Console.WriteLine(wrongDefined.Length);
}
}
""");
}
[Fact]
public async Task DoNotRemoveCastOnCallToMethodWithCorrectParamsArgs()
{
await TestMissingInRegularAndScriptAsync(
"""
class Program
{
public static void Main(string[] args)
{
TakesParams([|null as string|]);
}
private static void TakesParams(params string[] wrongDefined)
{
Console.WriteLine(wrongDefined.Length);
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/18978")]
public async Task RemoveCastOnCallToMethodWithParamsArgsIfImplicitConversionExists()
{
await TestInRegularAndScriptAsync(
"""
class Program
{
public static void Main(string[] args)
{
var takesArgs = new[] { "Hello", "World" };
TakesParams([|takesArgs as System.IComparable[]|]);
}
private static void TakesParams(params object[] goo)
{
System.Console.WriteLine(goo.Length);
}
}
""",
"""
class Program
{
public static void Main(string[] args)
{
var takesArgs = new[] { "Hello", "World" };
TakesParams(takesArgs);
}
private static void TakesParams(params object[] goo)
{
System.Console.WriteLine(goo.Length);
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/20630")]
public async Task DontRemoveCastOnCallToAttributeWithParamsArgs()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
using System.Reflection;
sealed class MarkAttribute : Attribute
{
public readonly string[] Arr;
public MarkAttribute(params string[] arr)
{
Arr = arr;
}
}
[Mark([|null as string|])] // wrong instance of: IDE0004 Cast is redundant.
static class Program
{
static void Main()
{
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/29264")]
public async Task RemoveCastOnDictionaryIndexer()
{
await TestInRegularAndScriptAsync(
"""
using System;
using System.Reflection;
using System.Collections.Generic;
static class Program
{
static void Main()
{
Dictionary<string, string> Icons = new Dictionary<string, string>
{
[[|"" as string|]] = null,
};
}
}
""",
"""
using System;
using System.Reflection;
using System.Collections.Generic;
static class Program
{
static void Main()
{
Dictionary<string, string> Icons = new Dictionary<string, string>
{
[""] = null,
};
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/20630")]
public async Task DontRemoveCastOnCallToAttributeWithParamsArgsAndProperty()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
sealed class MarkAttribute : Attribute
{
public MarkAttribute(params string[] arr)
{
}
public int Prop { get; set; }
}
[Mark([|null as string|], Prop = 1)]
static class Program
{
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/20630")]
public async Task DontRemoveCastOnCallToAttributeWithParamsArgsPropertyAndOtherArg()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
sealed class MarkAttribute : Attribute
{
public MarkAttribute(bool otherArg, params string[] arr)
{
}
public int Prop { get; set; }
}
[Mark(true, [|null as string|], Prop = 1)]
static class Program
{
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/20630")]
public async Task DontRemoveCastOnCallToAttributeWithParamsArgsNamedArgsAndProperty()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
sealed class MarkAttribute : Attribute
{
public MarkAttribute(bool otherArg, params string[] arr)
{
}
public int Prop { get; set; }
}
[Mark(arr: [|null as string|], otherArg: true, Prop = 1)]
static class Program
{
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/20630")]
public async Task DoRemoveCastOnCallToAttributeWithInvalidParamsArgs()
{
await TestInRegularAndScript1Async(
"""
using System;
sealed class MarkAttribute : Attribute
{
public MarkAttribute(bool otherArg, params string wrongDefined)
{
}
public int Prop { get; set; }
}
[Mark(true, [|null as string|], Prop = 1)]
static class Program
{
}
""",
"""
using System;
sealed class MarkAttribute : Attribute
{
public MarkAttribute(bool otherArg, params string wrongDefined)
{
}
public int Prop { get; set; }
}
[Mark(true, null, Prop = 1)]
static class Program
{
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/20630")]
public async Task DoNotRemoveCastOfNullToParamsArg()
{
await TestMissingAsync(
"""
using System;
using System.Reflection;
class MarkAttribute : Attribute
{
public readonly string[] Arr;
public MarkAttribute(params string[] arr)
{
Arr = arr;
}
}
[Mark([|(string)|]null)]
static class Program
{
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/20630")]
public async Task RemoveCastOnCallToAttributeWithParamsArgsWithImplicitCast()
{
await TestInRegularAndScriptAsync(
"""
using System;
sealed class MarkAttribute : Attribute
{
public MarkAttribute(bool otherArg, params object[] arr)
{
}
public int Prop { get; set; }
}
[Mark(arr: [|new[] { "Hello", "World" } as object[]|], otherArg: true, Prop = 1)]
static class Program
{
}
""",
"""
using System;
sealed class MarkAttribute : Attribute
{
public MarkAttribute(bool otherArg, params object[] arr)
{
}
public int Prop { get; set; }
}
[Mark(arr: new[] { "Hello", "World" }, otherArg: true, Prop = 1)]
static class Program
{
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/25456#issuecomment-373549735")]
public async Task DontIntroduceDefaultLiteralInSwitchCase()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
void M()
{
switch ("")
{
case [|default as string|]:
break;
}
}
}
""", parameters: new TestParameters(new CSharpParseOptions(LanguageVersion.CSharp7_1)));
}
[Fact]
public async Task DontIntroduceDefaultLiteralInSwitchCase_CastInsideParentheses()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
void M()
{
switch ("")
{
case ([|default as string|]):
break;
}
}
}
""", parameters: new TestParameters(new CSharpParseOptions(LanguageVersion.CSharp7_1)));
}
[Fact]
public async Task DontIntroduceDefaultLiteralInSwitchCase_DefaultInsideParentheses()
{
await TestMissingInRegularAndScriptAsync(
"""
class C
{
void M()
{
switch ("")
{
case [|(default) as string|]:
break;
}
}
}
""", parameters: new TestParameters(new CSharpParseOptions(LanguageVersion.CSharp7_1)));
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27239")]
public async Task DontOfferToRemoveCastWhereNoConversionExists()
{
await TestMissingInRegularAndScriptAsync(
"""
using System;
class C
{
void M()
{
object o = null;
TypedReference r2 = [|o as TypedReference|];
}
}
""");
}
[Fact, WorkItem("https://github.com/dotnet/roslyn/issues/28412")]
public async Task DontOfferToRemoveCastWhenAccessingHiddenProperty()
{
await TestMissingInRegularAndScriptAsync("""
using System.Collections.Generic;
class Fruit
{
public IDictionary<string, object> Properties { get; set; }
}
class Apple : Fruit
{
public new IDictionary<string, object> Properties { get; }
}
class Tester
{
public void Test()
{
var a = new Apple();
([|a as Fruit|]).Properties["Color"] = "Red";
}
}
""");
}
}
}
|