Testing

gof now has the first shipped slice of a real testing platform.

This is not the final test system yet. It is the first coherent baseline that lets user code and repository code share the same language-level test surface instead of treating assert(...) as a pseudo-framework.

Current surface

The shipped slice currently includes:

• test fn
• fixture(test) fn and fixture(module) fn
• the reserved stdlib import testing
• typed TestContext
• deterministic gof test discovery for *_test.gof and tests/**/*.gof
• snapshot storage under tests/snapshots/
• artifact-backed product fixtures under tests/ui, tests/runtime, and tests/runtime-fail
• optional fixture cleanup hooks through receiver method cleanup()
• markdown doctests through gof test --docs

Example:

import testing

test fn sums_are_stable(t: TestContext):
    case = t.case("small-sum")
    case.equal(2 + 3, 5, "expected deterministic integer addition")

test fn result_paths_stay_explicit(t: TestContext) -> Result[unit, RuntimeError]:
    parsed = parse_int("7")?
    return Result.Ok(t.equal(parsed, 7, "expected parse_int to preserve value"))

Run it with:

gof test examples/testing_baseline
gof test --list examples/testing_baseline
gof test --shuffle --seed 17 examples/testing_baseline

TestContext

The shipped testing stdlib currently exposes these baseline helpers:

• t.fail(message) — immediate test failure
• t.equal(actual, expected, message) — equality check
• t.not_equal(actual, expected, message) — inequality check
• t.true(condition, message) — boolean assertion
• t.false(condition, message) — negated boolean assertion
• t.ok(result, message) — assert Result is Ok
• t.err(result, message) — assert Result is Err
• t.match_snapshot(name, value) — snapshot comparison
• t.case(name) — sub-case scoping
• t.temp_dir() — create temporary directory
• t.temp_file(prefix) — create temporary file
• t.env(name, value) — scoped environment override
• t.skip(message) — skip the test
• t.todo(message) — mark as todo

Typed fixtures

Fixtures are explicit top-level functions that feed typed dependencies into tests and other fixtures.

import testing

fixture(module) fn shared_total() -> int:
    return 41

fixture(test) fn scratch_dir(t: TestContext) -> TempDir:
    return t.temp_dir()

test fn uses_fixtures(shared_total: int, scratch_dir: TempDir, t: TestContext):
    t.equal(shared_total, 41, "expected cached module fixture value")
    t.true(exists(scratch_dir.path()), "expected test fixture temp dir")

Current fixture rules:

• fixture(module) caches one value per test file during a gof test run
• fixture(test) creates one value per test case
• dependency injection resolves by parameter name and compatible type
• fixtures must declare an explicit return type
• only fixture(test) may request t: TestContext
• fixture values may declare an optional cleanup() receiver method

Snapshot contract

Snapshots are explicit and deterministic:

• they live under tests/snapshots/
• paths are derived from the source file path and nested t.case(...) names
• they update only when you pass --update-snapshots

Product fixtures

gof test now also owns the repository-style product harness paths:

• tests/ui/*.gof: the file must fail during compilation
• tests/runtime/*.gof: the file must execute successfully
• tests/runtime-fail/*.gof: the file must compile, then fail at runtime

Those paths use explicit artifact files: .diag, .stdout, .stderr, .exit.

JSON reporter

gof test --json emits one machine-readable report to stdout with stable schema gof.test.report/v1.

JUnit reporter

gof test --junit emits one JUnit/xUnit XML document to stdout.

Exit codes

gof test reserves two dedicated non-zero exit codes:

• 10: at least one discovered test target failed honestly
• 11: the test harness itself could not complete discovery, execution, or reporting honestly

Markdown doctests

gof test --docs has a shipped markdown baseline:

• ```gof doctest ``: compile and run
• ```gof doctest no_run ``: compile only
• ```gof doctest compile_fail ``: expect compilation failure
• ```gof doctest runtime_fail ``: expect runtime failure
• plain ```gof `` fences default to doctests only when the block looks like a whole-file example
• ```gof ignore and ```gof text force a fence to stay prose-only
• when gof test --docs targets the repository root, canonical discovery is limited to README.md, docs/site/content/docs/en/**/*.mdx, and docs/site/content/docs/ru/**/*.mdx

Current limits

Not shipped yet:

• property testing
• fuzzing
• concurrency stress
• benchmark integration
• default parallel execution