npx skills add ...
npx skills add dotnet/skills --skill filter-syntax
Reference-only filter syntax for VSTest and MTP with MSTest, NUnit, xUnit v3, and TUnit. Load only after the platform/framework is known and a consumer needs to create or translate a filter. Do not load for unfiltered runs or platform detection. Used by run-tests and mtp-hot-reload; never invoke directly.
npx skills add dotnet/skills --skill filter-syntax
Filter syntax depends on the platform and test framework.
Expression syntax: <Property><Operator><Value>[|&<Expression>]
Operators:
| Operator | Meaning |
|---|---|
= | Exact match |
!= | Not exact match |
~ | Contains |
!~ | Does not contain |
Combinators: | (OR), & (AND). Parentheses for grouping: (A|B)&C
Supported properties by framework:
| Framework | Properties |
|---|---|
| MSTest | FullyQualifiedName, Name, ClassName, Priority, TestCategory |
| xUnit | FullyQualifiedName, DisplayName, Traits |
| NUnit | FullyQualifiedName, Name, Priority, TestCategory |
An expression without an operator is treated as FullyQualifiedName~<value>.
Examples (VSTest):
MSTest and NUnit on MTP use the same --filter syntax as VSTest (same properties, operators, and combinators). The only difference is how the flag is passed:
xUnit v3 on MTP uses framework-specific filter flags instead of the generic --filter expression:
| Flag | Description |
|---|---|
--filter-class "name" | Run all tests in a given class |
--filter-not-class "name" | Exclude all tests in a given class |
--filter-method "name" | Run a specific test method |
--filter-not-method "name" | Exclude a specific test method |
--filter-namespace "name" | Run all tests in a namespace |
--filter-not-namespace "name" | Exclude all tests in a namespace |
--filter-trait "name=value" | Run tests with a matching trait |
--filter-not-trait "name=value" | Exclude tests with a matching trait |
Multiple values can be specified with a single flag: --filter-class Foo Bar.
For complex expressions, use --filter-query with a path-segment syntax:
Each segment matches against: assembly name, namespace, class name, method name. Use * for "match all" in any segment. Documentation: https://xunit.net/docs/query-filter-language
TUnit uses --treenode-filter with a path-based syntax:
Wildcards (*) are supported in any segment. Filter operators can be appended to test names for property-based filtering.
| Operator | Meaning |
|---|---|
* | Wildcard match |
= | Exact property match (e.g., [Category=Unit]) |
!= | Exclude property value |
& | AND (combine conditions) |
| | OR (within a segment, requires parentheses) |
Examples (TUnit):
MSTest, NUnit, and xUnit.net v2 (with YTest.MTP.XUnit2): The VSTest --filter syntax is identical on both VSTest and MTP. No changes needed.
xUnit.net v3 (native MTP): xUnit.net v3 does NOT support the VSTest --filter syntax on MTP. Translate filters using xUnit.net v3's native options:
VSTest --filter syntax | xUnit.net v3 MTP equivalent | Notes |
|---|---|---|
FullyQualifiedName~ClassName | --filter-class *ClassName* | Wildcards required for substring match |
FullyQualifiedName=Ns.Class.Method | --filter-method Ns.Class.Method | Exact match on fully qualified method |
Name=MethodName | --filter-method *MethodName* | Wildcards for substring match |
Category=Value (trait) | --filter-trait "Category=Value" | Filter by trait name/value pair |
| Complex expressions | --filter-query "expr" | Uses xUnit.net query filter language (see above) |