Config with xunit.runner.json
Configuration files can be used to configure xUnit.net on a per test-assembly basis.
Note
In these examples, we tell you to use the file name xunit.runner.json. You can also use <AssemblyName>.xunit.runner.json (where <AssemblyName> is the name of your unit test assembly, without the file extension like .dll or .exe). You should only need to use this longer name format if your unit tests DLLs will all be placed into the same output folder, and you need to disambiguate the various configuration files.
The assembly-specific filename takes precedence over the non-specific filename; there is no merging of values between files.
Adding the configuration file
Add a new JSON file to the root of your test project. Name the file
xunit.runner.json. Start with a schema reference so that text editors (like Visual Studio & Visual Studio Code) can provide auto-complete behavior while editing the file:{ "$schema": "https://xunit.net/schema/current/xunit.runner.schema.json" }Tell the build system to copy the file into the build output directory. Edit your
.csprojfile and add the following:<ItemGroup> <Content Include="xunit.runner.json" CopyToOutputDirectory="PreserveNewest" /> </ItemGroup>
Supported configuration items
The current schema is online at https://xunit.net/schema/current/xunit.runner.schema.json, which can be set in the JSON file to aid with intellisense from development IDEs like Visual Studio and Visual Studio Code.
Configuration elements are placed inside a top-level object:
{
"$schema": "https://xunit.net/schema/current/xunit.runner.schema.json",
"enum-or-string-key": "value1",
"boolean-key": true,
"integer-key": 42
}
All values list the minimum runner version that is required to support the configuration value (previous versions will ignore unknown configuration values). Features that require support from the test framework itself will also list the minimum version of the test framework required for the feature; if you don't see a minimum test framework version, then it means the feature is implemented purely in the runners and works with all test framework versions.
appDomain
Set this value to determine whether App Domains are used. By default, they will be used when available (the "ifAvailable" value). If you set this to "required", it will require that app domains are available; if you set this to "denied", it will not use app domains. Note that App Domains are only supported with .NET Framework tests, and only with tests linked against xUnit.net framework v1 or v2.
Runners v2 2.1+, v3 Test framework v1, v2 JSON schema type String Valid values "required","ifAvailable","denied"Default value "ifAvailable"
assertEquivalentMaxDepth
Set this value to limit the recursive depth Assert.Equivalent will use when comparing objects for equivalence.
This can also be set by environment variable XUNIT_ASSERT_EQUIVALENT_MAX_DEPTH. A value in the configuration file will take precedence over the environment variable.
Runners v3 1.1+ Test framework v3 1.1+ JSON schema type 32-bit integer Minimum value 1Default value 50
culture
Set this value to override the default culture used to run all unit tests in the assembly. You can pass "default" to use the default behavior (use the default culture of the operating system); you can pass "invariant" to use the invariant culture; or you can pass any string which describes a valid culture on the target operating system (see BCP 47 for a description of how culture names are formatted; note that the list of supported cultures will vary by target operating system).
Runners v3 Test framework v3 JSON schema type String Default value "default"
diagnosticMessages
Set this value to true to include diagnostic information during test discovery and execution. Each runner has a unique method of presenting diagnostic messages.
Runners v2 2.1+, v3 Test framework v2, v3 JSON schema type Boolean Default value false
failSkips
Set this to true to enable skipped tests to be treated as errors.
Runners v2 2.5+, v3 JSON schema type Boolean Default value false
failWarns
Set this to true to enable warned tests to be treated as errors. By default, warnings will be reported with a passing test result.
Runners v3 Test framework v3 JSON schema type Boolean Default value false
internalDiagnosticMessages
Set this value to true to include internals diagnostic information during test discovery and execution. Each runner has a unique method of presenting diagnostic messages. Internal diagnostics often include information that is only useful when debugging the test framework itself.
Runners v2 2.1+, v3 Test framework v2, v3 JSON schema type Boolean Default value false
longRunningTestSeconds
Set this value to enable long-running (hung) test detection. When the runner is idle waiting for tests to finished, it will report that fact once the timeout has passed. Use a value of 0 to disable the feature, or a positive integer value to enable the feature (time in seconds).
NOTE: Long running test messages are diagnostic messages. You must enable diagnostic messages in order to see the long running test warnings.
Runners v2 2.2+, v3 JSON schema type 32-bit integer Minimum value 0Default value 0(disabled)
maxParallelThreads
Set this to override the maximum number of threads to be used when parallelizing tests within this assembly. Use a value of 0 (or "default"1) to indicate that you would like the default behavior; use a value of -1 (or "unlimited"1) to indicate that you do not wish to limit the number of threads used for parallelization; use a value with the multiplier syntax1 (i.e., values like "0.5x" or "2x") to indicate that you wish you have a multiple of the number of CPU threads (so 2x indicates you want the number of maximum parallel threads to be 2 * the number of CPU threads).
1 NOTE: While this configuration value has been present since v2 2.1, the newer values ("default", "unlimited", and the multiplier syntax) are only supported with Runners v2 2.8 and later (and all Runners v3).
Runners v2 2.1+, v3 Test framework v2, v3 JSON schema type 32-bit integer (schema v2.1+), 32-bit integer or string (schema v2.8+) Default value The number of CPU threads
methodDisplay
Set this to override the default display name for test cases. If you set this to "method", the display name will be just the method (without the class name); if this set this value to "classAndMethod", the default display name will be the fully qualified class name and method name.
Runners v2 2.1+, v3 Test framework v2, v3 JSON schema type String Valid values "method","classAndMethod"Default value "classAndMethod"
methodDisplayOptions
Set this to automatically perform transforms on default test names. This value can either be all, none, or a comma-separated combination of one or more of the following values:
"replaceUnderscoreWithSpace"replaces all underscores with spaces."useOperatorMonikers"replaces operator names with matching symbols. Replacements:eqbecomes=nebecomes!=ltbecomes<lebecomes<=gtbecomes>gebecomes>=
"useEscapeSequences"replaces escape sequences in the formatXnnorUnnnnwith their ASCII or Unicode character equivalents. Examples:X2Cbecomes,U1D13becomesᴓ
"replacePeriodWithComma"replaces periods with a comma and a space. This option is typically only useful ifmethodDisplayisclassAndMethod.
Runners v2 2.4+, v3 Test framework v2, v3 JSON schema type String flags Valid values "all","none", or comma separated flagsDefault value "none"
parallelAlgorithm
Set this to change the way tests are scheduled when they're running in parallel. For more information, see Running Tests in Parallel. Note that the algorithm only applies when you have enabled test collection parallelism, and are using a limited number of threads (i.e., not unlimited or -1).
Runners v2 2.8+, v3 Test framework v2 2.8+, v3 JSON schema type String Valid values "conservative","aggressive"Default value "conservative"
parallelizeAssembly
Set this to true if this assembly is willing to participate in parallelization with other assemblies. Test runners can use this information to automatically enable parallelization across assemblies if all the assemblies agree to it.
Runners v2 2.1+, v3 Test framework v2, v3 JSON schema type Boolean Default value false
parallelizeTestCollections
Set this to true if the assembly is willing to run tests inside this assembly in parallel against each other. Tests in the same test collection will be run sequentially against each other, but tests in different test collections will be run in parallel against each other. Set this to false to disable all parallelization within this test assembly.
Runners v2 2.1+, v3 Test framework v2, v3 JSON schema type Boolean Default value true
preEnumerateTheories
Set this to true to pre-enumerate theories so that there is an individual test case for each theory data row. Set this to false to return a single test case for each theory without pre-enumerating the data ahead of time (this is how xUnit.net v1 used to behave). This is most useful for developers running tests inside Visual Studio, who wish to have the Code Lens test runner icons on their theory methods, since Code Lens does not support multiple tests from a single method.
This value does not have a default, because it's up to each individual test runner to decide what the best default behavior is. The Visual Studio adapter, for example, will default to true, while the console and MSBuild runners will default to false.
Runners v2 2.1+, v3 Test framework v2, v3 JSON schema type Boolean
printMaxEnumerableLength
Set this value to limit the number of items to print in a collection (followed by an ellipsis when the collection is longer). This is also used when printing into the middle of a collection with a mismatch index, which means the printing may also start with an ellipsis.
Set this to 0 to always print the full collection.
This can also be set by environment variable XUNIT_PRINT_MAX_ENUMERABLE_LENGTH. A value in the configuration file will take precedence over the environment variable.
Runners v3 1.1+ Test framework v3 1.1+ JSON schema type 32-bit integer Minimum value 0Default value 5
printMaxObjectDepth
Set this value to limit the recursive depth when printing objects (followed by an ellipsis when the object depth is too deep).
Set this to 0 to always print objects at all depths.
Warning
Disabling this when printing objects with circular references could result in an infinite loop that will cause an OutOfMemoryException and crash the test runner process.
This can also be set by environment variable XUNIT_PRINT_MAX_OBJECT_DEPTH. A value in the configuration file will take precedence over the environment variable.
Runners v3 1.1+ Test framework v3 1.1+ JSON schema type 32-bit integer Minimum value 0Default value 3
printMaxObjectMemberCount
Set this value to limit the the number of members (fields and properties) to include when printing objects (followed by an ellipsis when there are more members).
Set this to 0 to always print all members.
This can also be set by environment variable XUNIT_PRINT_MAX_OBJECT_MEMBER_COUNT. A value in the configuration file will take precedence over the environment variable.
Runners v3 1.1+ Test framework v3 1.1+ JSON schema type 32-bit integer Minimum value 0Default value 5
printMaxStringLength
Set this value to limit the number of characters to print in a string (followed by an ellipsis when the collection is longer). This is also used when printing into the middle of a string with a mismatch index, which means the printing may also start with an ellipsis.
Set this to 0 to always print full strings.
This can also be set by environment variable XUNIT_PRINT_MAX_STRING_LENGTH. A value in the configuration file will take precedence over the environment variable.
Runners v3 1.1+ Test framework v3 1.1+ JSON schema type 32-bit integer Minimum value 0Default value 50
seed
Set this to set the seed used for randomization (affects how the test cases are randomized). This is only valid for v3.0+ test assemblies; it will be ignored for v1 or v2 assemblies. If the seed value isn't set, then the system will determine a reasonable seed (and print that seed when running the test assembly, to assist you in reproducing order-dependent failures).
Runners v3 Test framework v3 JSON schema type 32-bit integer Minimum value 0Default value unset
shadowCopy
Set this to true to use shadow copying when running tests in separate app domains; set to false to run tests without shadow copying. When running tests without app domains, this value is ignored.
This value is only valid for .NET Framework test projects targeting xUnit.net v1 and v2.
Runners v2 2.1+, v3 Test framework v1, v2 JSON schema type Boolean Default value true
showLiveOutput
Set this to true to show messages from ITestOutputHelper live during the test run, in addition to showing them after the test has completed; set to false to only show test output messages after the test has completed.
Note
When using dotnet test you may need to pass --logger "console;verbosity=normal" to be able to see messages from xUnit.net, as they may be hidden by default.
Runners v2 2.8.1+, v3 Test framework v2, v3 JSON schema type Boolean Default value false
stopOnFail
Set this to true to stop running further tests once a test has failed. (Because of the asynchronous nature of test execution, this will not necessarily happen immediately; any test that is already in flight may complete, which may result in multiple test failures reported.)
Runners v2 2.5+, v3 Test framework v2, v3 JSON schema type Boolean Default value false