writing-mstest-tests
Write, create, modernize, or fix comprehensive MSTest unit tests with MSTest 3.x/4.x APIs. USE FOR: write, create, review, or modernize MSTest tests and assertions, better MSTest assertion than Assert.IsTrue, replace hard cast with IsInstanceOfType, MSTest assertion APIs (Contains, ContainsSingle, HasCount, IsEmpty, IsNotEmpty, DoesNotContain, AreSame, IsNull, StartsWith, EndsWith, MatchesRegex, IsGreaterThan, IsLessThan, IsInRange), swapped/reversed Assert.AreEqual args (Expected/Actual backwards), replace ExpectedException with Assert.Throws, data-driven (DataRow, DynamicData, ValueTuples),
Profile →npx skills add dotnet/skills --skill writing-mstest-tests --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# Writing MSTest Tests Help users write effective, modern unit tests with MSTest 3.x/4.x using current APIs and best practices. ## When to Use - User wants to write new MSTest unit tests - User wants to improve or modernize existing MSTest tests by implementing concrete fixes - User asks about MSTest assertion APIs, data-driven patterns, or test lifecycle - User asks to replace `Assert.IsTrue` with more specific assertions (collections, nulls, types, comparisons) - User asks to replace hard casts with type-checking assertions in tests - User needs help fixing a specific MSTest test bug or failing assertion - User asks to fix swapped `Assert.AreEqual` argument order (expected first, actual second) - User asks to convert `DynamicData` from `IEnumerable<object[]>` to ValueTuple-based data - User asks to fix or understand an MSTest analyzer diagnostic (an `MSTESTxxxx` warning/error) ## When Not to Use - User needs a test quality audit, anti-pattern detection, or flaky-test investigation (use `test-anti-patterns`) - User needs to run or execute tests (use the `run-tests` skill) - User needs to upgrade from MSTest v1/v2 to v3 (use `migrate-mstest-v1v2-to-v3`) - User needs to upgrade from
- When to Use
- When Not to Use
- Inputs
- Response Guidelines
- Workflow
- Step 1: Determine project setup
- Step 2: Write test classes following conventions
- Step 3: Use modern assertion APIs
- Step 4: Use data-driven tests for multiple inputs
- Step 5: Handle test lifecycle correctly
- Step 6: Apply cancellation and timeout patterns
- Step 7: Use advanced features where appropriate
- Step 8: Fix MSTest analyzer diagnostics (MSTESTxxxx)
What does the writing-mstest-tests skill do?
Write, create, modernize, or fix comprehensive MSTest unit tests with MSTest 3.x/4.x APIs. USE FOR: write, create, review, or modernize MSTest tests and assertions, better MSTest assertion than Assert.IsTrue, replace hard cast with IsInstanceOfType, MSTest assertion APIs (Contains, ContainsSingle, HasCount, IsEmpty, IsNotEmpty, DoesNotContain, AreSame, IsNull, StartsWith, EndsWith, MatchesRegex, IsGreaterThan, IsLessThan, IsInRange), swapped/reversed Assert.AreEqual args (Expected/Actual backwards), replace ExpectedException with Assert.Throws, data-driven (DataRow, DynamicData, ValueTuples),
How do I install it?
Run `npx skills add dotnet/skills --skill writing-mstest-tests --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From dotnet/skills, a repository with 4,927 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.