.NET Verify Snapshot Testing

Manage Verify snapshot tests using the verify.tool dotnet local tool.

Discovery

To list all test files using Verify snapshots:

rg -l "Verifier\\.Verify|UsesVerify|\\.verified\\." --type cs

To scope to a specific directory:

rg -l "Verifier\\.Verify|UsesVerify|\\.verified\\." --type cs <path/to/test/directory>

Update Snapshots

To update snapshots after intentional code changes:

1. Build the solution:

   dotnet build -p:WarningLevel=0 /clp:ErrorsOnly --verbosity minimal
   

2. Run affected verify tests (they fail, generating .received. files):

   dotnet test <test-project> --no-build --filter "FullyQualifiedName~" -v m
   

3. Accept all new snapshots:

   dotnet verify accept -y
   

   To scope to a specific directory:

   dotnet verify accept -y -w <path/to/test/directory>
   

4. Re-run tests to confirm they pass:

   dotnet test <test-project> --no-build --filter "FullyQualifiedName~" -v m
   

File Conventions

• ClassName.MethodName.verified.txt — accepted snapshot (committed to git)
• ClassName.MethodName.received.txt — latest test output (not committed, gitignored)
• Parameterized tests: ClassName.MethodName_param=value.verified.txt

Quick Reference