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@Copilot Copilot AI commented Aug 1, 2025

This PR implements a new MSTest analyzer PreferTestContextWriteAnalyzer (MSTEST0053) that detects usage of Console.Write*, Trace.Write*, and Debug.Write* methods in test methods and test lifecycle methods, and provides an automatic code fixer to replace them with TestContext.WriteLine.

Problem

When developers use Console.Write, Console.WriteLine, Trace.Write, Trace.WriteLine, Debug.Write, or Debug.WriteLine in test methods or test lifecycle methods, the output may be lost or not properly captured by the test framework. This makes debugging tests more difficult and can result in important diagnostic information being missed.

Solution

The new analyzer detects these problematic patterns in:

  • Test methods ([TestMethod])
  • Test lifecycle methods ([TestInitialize], [TestCleanup], [ClassInitialize], [ClassCleanup], [AssemblyInitialize], [AssemblyCleanup])

The included code fixer automatically replaces the problematic calls with TestContext.WriteLine to ensure test output is properly captured and displayed by the test framework.

Example

Before (triggers MSTEST0053):

[TestClass]
public class MyTestClass
{
    [TestMethod]
    public void MyTest()
    {
        Console.WriteLine("Debug info");     // ❌ MSTEST0053: Use 'TestContext.WriteLine' instead
        Trace.WriteLine("Trace info");       // ❌ MSTEST0053: Use 'TestContext.WriteLine' instead
        Debug.WriteLine("Debug info");       // ❌ MSTEST0053: Use 'TestContext.WriteLine' instead
    }

    [TestInitialize]
    public void Setup()
    {
        Console.WriteLine("Setup info");     // ❌ MSTEST0053: Use 'TestContext.WriteLine' instead
    }
}

After (with code fixer applied):

[TestClass]
public class MyTestClass
{
    public TestContext TestContext { get; set; }

    [TestMethod]
    public void MyTest()
    {
        TestContext.WriteLine("Debug info"); // ✅ Properly captured by test framework
        TestContext.WriteLine("Trace info"); // ✅ Properly captured by test framework
        TestContext.WriteLine("Debug info"); // ✅ Properly captured by test framework
    }

    [TestInitialize]
    public void Setup()
    {
        TestContext.WriteLine("Setup info"); // ✅ Properly captured by test framework
    }
}

Implementation Details

  • Diagnostic ID: MSTEST0053
  • Category: Usage
  • Severity: Warning
  • Scope: Methods with test-related attributes ([TestMethod], [TestInitialize], [TestCleanup], [ClassInitialize], [ClassCleanup], [AssemblyInitialize], [AssemblyCleanup])
  • Code Fixer: Automatically replaces problematic calls with TestContext.WriteLine
  • Localization: Full support for 13 languages
  • Target Methods: Write and WriteLine methods on Console, Trace, and Debug types

Files Modified

  • Added PreferTestContextWriteAnalyzer.cs - Main analyzer implementation
  • Added PreferTestContextWriteCodeFixer.cs - Automatic code fixer
  • Added PreferTestContextWriteAnalyzerTests.cs - Comprehensive unit tests including code fixer tests
  • Updated DiagnosticIds.cs - Added MSTEST0053 diagnostic ID
  • Updated WellKnownTypeNames.cs - Added Console, Trace, Debug type names
  • Updated Resources.resx - Added localized resource strings
  • Updated CodeFixResources.resx - Added code fixer resource strings
  • Updated AnalyzerReleases.Unshipped.md - Added analyzer documentation
  • Updated all 13 XLF files - Added localization entries for both analyzer and code fixer

The analyzer follows MSTest analyzer patterns and integrates seamlessly with the existing analyzer infrastructure. The code fixer provides immediate, automated resolution of the detected issues.

Fixes #6285.


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@Copilot Copilot AI changed the title [WIP] Add analyzer for Console.Write**, Trace.Write**, and Debug.Write** usage in tests to suggest using TestContext instead. Add analyzer for Console.Write*, Trace.Write*, and Debug.Write* usage in tests (MSTEST0053) Aug 1, 2025
@Copilot Copilot AI requested a review from Evangelink August 1, 2025 15:32
Copilot finished work on behalf of Evangelink August 1, 2025 15:32
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@Youssef1313 do we want to be conditioned to having the capture enabled? I mean that if CaptureTraceOutput is set to false, we may want to avoid reporting.

@Copilot Copilot AI requested a review from Evangelink August 1, 2025 15:47
Copilot finished work on behalf of Evangelink August 1, 2025 15:47
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Please add a fixer.

Please also add tests for calls in:

  • AssemblyInit method
  • AssemblyClenaup method
  • ClassInit method
  • ClassCleanup method
  • TestInit method
  • TestCleanup method

Also, please add a test with a method called by a test method.

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Copilot AI commented Aug 4, 2025

Please add a fixer.

Please also add tests for calls in:...

Added PreferTestContextWriteCodeFixer with full localization support, expanded analyzer to detect usage in all test lifecycle methods (AssemblyInit, AssemblyCleanup, ClassInit, ClassCleanup, TestInit, TestCleanup), and added comprehensive tests including code fix verification. Commit: c1eb25d

@Copilot Copilot AI changed the title Add analyzer for Console.Write*, Trace.Write*, and Debug.Write* usage in tests (MSTEST0053) Add analyzer for Console.Write*, Trace.Write*, and Debug.Write* usage in tests with code fixer (MSTEST0053) Aug 4, 2025
@Copilot Copilot AI requested a review from Evangelink August 4, 2025 07:31
Copilot finished work on behalf of Evangelink August 4, 2025 07:31
namespace MSTest.Analyzers.Test;

[TestClass]
public sealed class PreferTestContextWriteAnalyzerTests
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Every test with a diagnostic should have the equivalent code fixer.

[TestMethod]
public void MyTestMethod()
{
TestContext.WriteLine("test");
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Original code is using Write so after codefix we should use Write

MessageFormat,
Description,
Category.Usage,
DiagnosticSeverity.Warning,
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It should be Info

@Youssef1313 Youssef1313 closed this Sep 1, 2025
@Youssef1313 Youssef1313 deleted the copilot/fix-6285 branch September 1, 2025 12:44
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Add analyzer for Console.Write**, Trace.Write**, and Debug.Write** usage in tests to suggest using TestContext instead.
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