Testing

Silt has a built-in test runner invoked with silt test. It discovers and runs test functions without any configuration.

File Conventions

Test files must use one of these naming patterns to be auto-discovered:

• *_test.silt (e.g. math_test.silt)
• *.test.silt (e.g. math.test.silt)

Without a path argument, silt test searches the current directory recursively. You can also pass a specific file or directory:

silt test                      -- search current directory recursively
silt test tests/               -- search tests/ directory recursively
silt test math_test.silt       -- run a single file

Function Conventions

Within a test file, functions are recognized by their name prefix:

• test_* — recognized as a test and executed
• skip_test_* — shown as skipped, not executed
• Any other function name — ignored by the test runner (available as helpers)

import test
import string

fn test_addition() {
    test.assert_eq(1 + 1, 2)
}

fn test_string_length() {
    test.assert_eq(string.length("hello"), 5)
}

fn skip_test_not_ready_yet() {
    test.assert(false, "this would fail")
}

fn helper(x) {
    x * 2
}

fn test_with_helper() {
    test.assert_eq(helper(3), 6)
}

Running this file produces:

  PASS math_test.silt::test_addition
  PASS math_test.silt::test_string_length
  SKIP math_test.silt::skip_test_not_ready_yet
  PASS math_test.silt::test_with_helper

4 tests: 3 passed, 0 failed, 1 skipped

Filtering Tests

Use --filter <pattern> to run only tests whose names contain the pattern:

silt test --filter addition     -- runs only test_addition
silt test --filter string       -- runs only test_string_length

The filter matches against the function name (not the file name). Files that cannot contain any matching test are skipped entirely.

Assertions

The test module provides assertion functions. See the test module reference for details.

All assertions accept an optional trailing String message argument.

Exit Code

silt test exits with code 0 if all tests pass and code 1 if any test fails.