title	description	author	ms.author	ms.date
MSTest code analysis	Learn about the MSTest code analysis.	evangelink	amauryleve	12/20/2023

MSTest code analysis

MSTest analysis ("MSTESTxxxx") rules inspect your C# or Visual Basic code for security, performance, design and other issues.

Tip

If you're using Visual Studio, many analyzer rules have associated code fixes that you can apply to correct the problem. Code fixes are shown in the light bulb icon menu.

The rules are organized into categories such as performance usage...

Starting with MSTest.TestFramework 3.7, the MSTest.Analyzers NuGet package is a dependency of the framework. For earlier versions, you need to use MSTest metapackage or add a package reference for MSTest.Analyzers explicitly.

MSTestAnalysisMode

Starting with MSTest 3.8, an MSBuild property named MSTestAnalysisMode is available to determine which analyzers are enabled at which severity.

Tip

To see which rules are enabled at which severity for each mode, you can navigate to the package of the version of interest in NuGet cache, locate the globalconfigs directory, and open the .globalconfig file corresponding to the analysis mode. For more information on finding the NuGet cache directory, see Managing the global packages, cache, and temp folders. From that directory, locate mstest.analyzers directory, then the version (3.8 and higher), then globalconfigs. Alternatively, you can download the NuGet package of the version of interest from nuget.org and view it in NuGet Package Explorer (Windows app), or view directly in the web app version of NuGet Package Explorer.

The available values for this property:

None
Default
Recommended
All

`None`

This value sets all analyzers to none severity, disabling all of them. You can then enable individual analyzers using .editorconfig or .globalconfig files.

`Default`

This setting follows the default documented behavior for each rule.

Rules that are enabled by default will use their default severity.
Rules that are disabled by default will use none severity.

Note

Rules that are enabled by default as warnings are violations that are expected to cause issues at run time.

`Recommended`

This is the mode most developers are expected to use. Rules that are enabled by default with Info (suggestion) severity are escalated to warnings. The following rules are escalated to errors in both Recommended and All modes:

MSTEST0003: Test methods should have valid layout.
MSTEST0043: Use retry attribute on test method.

`All`

This mode is more aggressive than Recommended. All rules are enabled as warnings. In addition, the following rules are escalated to errors:

MSTEST0003: Test methods should have valid layout.
MSTEST0043: Use retry attribute on test method.

Note

The following rules are completely opt-in and are not enabled in Default, Recommended, or All modes:

MSTEST0015: Test method should not be ignored
MSTEST0019: Prefer TestInitialize methods over constructors
MSTEST0020: Prefer constructors over TestInitialize methods
MSTEST0021: Prefer Dispose over TestCleanup methods
MSTEST0022: Prefer TestCleanup over Dispose methods

Categories

Design rules

Design rules help you create and maintain test suites that adhere to proper design and good practices.

Performance rules

Performance rules support high-performance testing.

Suppression rules

Suppression rules support suppressing diagnostics from other rules.

Usage rules

Usage rules support proper usage of MSTest.

MSTESTEXP

Several APIs of MSTest are decorated with the xref:System.Diagnostics.CodeAnalysis.ExperimentalAttribute. This attribute indicates that the API is experimental and may be removed or changed in future versions of MSTest. The attribute is used to identify APIs that aren't yet stable and may not be suitable for production use.

The MSTESTEXP diagnostic alerts you to use of an experimental API in your code. To suppress this diagnostic with the SuppressMessageAttribute, add the following code to your project:

using System.Diagnostics.CodeAnalysis;

[assembly: SuppressMessage("MSTESTEXP", "Justification")]

Alternatively, you can suppress this diagnostic with preprocessor directive by adding the following code to your project:

#pragma warning disable MSTESTEXP
        // API that is causing the warning.
#pragma warning restore MSTESTEXP

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!