Crate tryfn

Harness for discovering test inputs and asserting against snapshot files

This is a custom test harness and should be put in its own test binary with test.harness = false.

Examples

fn some_func(num: usize) -> usize {
    // ...
}

tryfn::Harness::new(
    "tests/fixtures/invalid",
    setup,
    test,
)
.select(["tests/cases/*.in"])
.test();

fn setup(input_path: std::path::PathBuf) -> tryfn::Case {
    let name = input_path.file_name().unwrap().to_str().unwrap().to_owned();
    let expected = tryfn::Data::read_from(&input_path.with_extension("out"), None);
    tryfn::Case {
        name,
        fixture: input_path,
        expected,
    }
}

fn test(input_path: &std::path::Path) -> Result<usize, Box<dyn std::error::Error>> {
    let raw = std::fs::read_to_string(input_path)?;
    let num = raw.parse::<usize>()?;

    let actual = some_func(num);

    Ok(actual)
}

Structs

• Case
  A test case enumerated by the Harness with data from the Setup function
• Data
  Test fixture, actual output, or expected result
• Harness
  Harness for discovering test inputs and asserting against snapshot files

Enums

• DataFormat
  Describes the structure of Data

Traits

• Setup
  Function signature for generating a test Case from a path fixture
• Test
  Function signature for running a test Case