File: ComponentParameterUsageAnalyzerTest.cs
Web Access
Project: src\src\Components\Analyzers\test\Microsoft.AspNetCore.Components.Analyzers.Tests.csproj (Microsoft.AspNetCore.Components.Analyzers.Tests)
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.Diagnostics;
using TestHelper;
 
namespace Microsoft.AspNetCore.Components.Analyzers;
 
public class ComponentParameterUsageAnalyzerTest : DiagnosticVerifier
{
    public ComponentParameterUsageAnalyzerTest()
    {
        ComponentTestSource = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class TestComponent : IComponent
        {{
            [Parameter] public string TestProperty {{ get; set; }}
            [Parameter] public int TestInt {{ get; set; }}
            public string NonParameter {{ get; set; }}
        }}
    }}" + ComponentsTestDeclarations.Source;
    }
 
    private string ComponentTestSource { get; }
 
    [Fact]
    public void ComponentPropertySimpleAssignment_Warns()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class OtherComponent : IComponent
        {{
            private TestComponent _testComponent;
            void Render()
            {{
                _testComponent = new TestComponent();
                _testComponent.TestProperty = ""Hello World"";
            }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test,
            new DiagnosticResult
            {
                Id = DiagnosticDescriptors.ComponentParametersShouldNotBeSetOutsideOfTheirDeclaredComponent.Id,
                Message = "Component parameter 'TestProperty' should not be set outside of its component.",
                Severity = DiagnosticSeverity.Warning,
                Locations = new[]
                {
                        new DiagnosticResultLocation("Test0.cs", 11, 17)
                }
            });
    }
 
    [Fact]
    public void ComponentPropertyCoalesceAssignment__Warns()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class OtherComponent : IComponent
        {{
            private TestComponent _testComponent;
            void Render()
            {{
                _testComponent = new TestComponent();
                _testComponent.TestProperty ??= ""Hello World"";
            }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test,
            new DiagnosticResult
            {
                Id = DiagnosticDescriptors.ComponentParametersShouldNotBeSetOutsideOfTheirDeclaredComponent.Id,
                Message = "Component parameter 'TestProperty' should not be set outside of its component.",
                Severity = DiagnosticSeverity.Warning,
                Locations = new[]
                {
                        new DiagnosticResultLocation("Test0.cs", 11, 17)
                }
            });
    }
 
    [Fact]
    public void ComponentPropertyCompoundAssignment__Warns()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class OtherComponent : IComponent
        {{
            private TestComponent _testComponent;
            void Render()
            {{
                _testComponent = new TestComponent();
                _testComponent.TestProperty += ""Hello World"";
            }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test,
            new DiagnosticResult
            {
                Id = DiagnosticDescriptors.ComponentParametersShouldNotBeSetOutsideOfTheirDeclaredComponent.Id,
                Message = "Component parameter 'TestProperty' should not be set outside of its component.",
                Severity = DiagnosticSeverity.Warning,
                Locations = new[]
                {
                        new DiagnosticResultLocation("Test0.cs", 11, 17)
                }
            });
    }
 
    [Fact]
    public void ComponentPropertyIncrement_Warns()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class OtherComponent : IComponent
        {{
            private TestComponent _testComponent;
            void Render()
            {{
                _testComponent = new TestComponent();
                _testComponent.TestInt++;
            }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test,
            new DiagnosticResult
            {
                Id = DiagnosticDescriptors.ComponentParametersShouldNotBeSetOutsideOfTheirDeclaredComponent.Id,
                Message = "Component parameter 'TestInt' should not be set outside of its component.",
                Severity = DiagnosticSeverity.Warning,
                Locations = new[]
                {
                        new DiagnosticResultLocation("Test0.cs", 11, 17)
                }
            });
    }
 
    [Fact]
    public void ComponentPropertyDecrement_Warns()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class OtherComponent : IComponent
        {{
            private TestComponent _testComponent;
            void Render()
            {{
                _testComponent = new TestComponent();
                _testComponent.TestInt--;
            }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test,
            new DiagnosticResult
            {
                Id = DiagnosticDescriptors.ComponentParametersShouldNotBeSetOutsideOfTheirDeclaredComponent.Id,
                Message = "Component parameter 'TestInt' should not be set outside of its component.",
                Severity = DiagnosticSeverity.Warning,
                Locations = new[]
                {
                        new DiagnosticResultLocation("Test0.cs", 11, 17)
                }
            });
    }
 
    [Fact]
    public void ComponentPropertyExpression_Ignores()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class TypeName
        {{
            void Method()
            {{
                System.IO.Console.WriteLine(new TestComponent().TestProperty);
            }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test);
    }
 
    [Fact]
    public void ComponentPropertyExpressionInStatement_Ignores()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class TypeName
        {{
            void Method()
            {{
                var testComponent = new TestComponent();
                for (var i = 0; i < testComponent.TestProperty.Length; i++)
                {{
                }}
            }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test);
    }
 
    [Fact]
    public void RetrievalOfComponentPropertyValueInAssignment_Ignores()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class TypeName
        {{
            void Method()
            {{
                var testComponent = new TestComponent();
                AnotherProperty = testComponent.TestProperty;
            }}
 
            public string AnotherProperty {{ get; set; }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test);
    }
 
    [Fact]
    public void ShadowedComponentPropertyAssignment_Ignores()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class TypeName
        {{
            void Method()
            {{
                var testComponent = new InheritedComponent();
                testComponent.TestProperty = ""Hello World"";
            }}
        }}
 
        class InheritedComponent : TestComponent
        {{
            public new string TestProperty {{ get; set; }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test);
    }
 
    [Fact]
    public void InheritedImplicitComponentPropertyAssignment_Ignores()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class TypeName : TestComponent
        {{
            void Method()
            {{
                this.TestProperty = ""Hello World"";
            }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test);
    }
 
    [Fact]
    public void ImplicitComponentPropertyAssignment_Ignores()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class TypeName : IComponent
        {{
            void Method()
            {{
                TestProperty = ""Hello World"";
            }}
 
            [Parameter] public string TestProperty {{ get; set; }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test);
    }
 
    [Fact]
    public void ComponentPropertyAssignment_NonParameter_Ignores()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class OtherComponent : IComponent
        {{
            private TestComponent _testComponent;
            void Render()
            {{
                _testComponent = new TestComponent();
                _testComponent.NonParameter = ""Hello World"";
            }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test);
    }
 
    [Fact]
    public void NonComponentPropertyAssignment_Ignores()
    {
        var test = $@"
    namespace ConsoleApplication1
    {{
        using {typeof(ParameterAttribute).Namespace};
        class OtherComponent : IComponent
        {{
            private SomethingElse _testNonComponent;
            void Render()
            {{
                _testNonComponent = new NotAComponent();
                _testNonComponent.TestProperty = ""Hello World"";
            }}
        }}
        class NotAComponent
        {{
            [Parameter] public string TestProperty {{ get; set; }}
        }}
    }}" + ComponentTestSource;
 
        VerifyCSharpDiagnostic(test);
    }
 
    protected override DiagnosticAnalyzer GetCSharpDiagnosticAnalyzer() => new ComponentParameterUsageAnalyzer();
}