Testing errors

While testing the happy path is a good start, you might also want to verify that expressions throw the error you expect. You check for a specifc type of error by setting expectedError.type and/or use expectedError.msg to search its message for the given regex.

Example:

tests/default.nix

{
  testCatchMessage = {
    expr = throw "10 instead of 5";
    expectedError.type = "ThrownError";
    expectedError.msg = "\\d+ instead of 5";
  };
}

->

✅ testCatchMessage

🎉 1/1 successful

Note: Regular expression like the one above are supported

Supported error types

The following values for expectedError.type are valid:

• RestrictedPathError
• MissingArgumentError
• UndefinedVarError
• TypeError
• Abort
• ThrownError
• AssertionError
• ParseError
• EvalError