OneCAD/docs/book/src/dev/testing.md

Test harnesses

cargo xtask ci runs everything a pull request must pass: fmt, xtask assets, xtask licences --check, xtask layers, clippy with -D warnings, the tests with the ci profile and the wasm build check.

Harness	Where	What it catches
Unit and engine tests	next to the code, *_tests.rs	measured results: volume, area, topology counts against derived values
Hostile input	hostile_params_never_panic, crates/engine/src/tests.rs	every command × every documented parameter × junk values: errors, never panics
Sketch fuzz	crates/engine/src/cmd/sketch_fuzz_tests.rs	random sketches through the solver and profile finder
UI scenarios	crates/ui-egui/tests/scenarios/*.json	the real app, headless: clicks, keys, drags, assertions
Layout tests	crates/ui-egui/tests/ui_layout.rs, window_widths.rs	panels and dialogs at every window width
Design-file corpus	apps/solvecraft-cli/tests/corpus	every saved file version still opens and evaluates the same
Kill mid-save	apps/solvecraft-cli/tests/kill_mid_save.rs	a save killed at any moment leaves a readable file
Fusion oracle	cargo xtask oracle → docs/oracle.md	parts rebuilt from recipes, compared with Fusion's measurements
STEP corpus	cargo xtask step-corpus → docs/step-import.md	STEP files from Fusion opened and measured

UI scenarios

A scenario is a JSON list of steps run against the real app with a headless egui context:

[
  {"start": "sketch.create"},
  {"click": {"plane": "XY"}},
  {"start": "sketch.rectangle.two_point"},
  {"click": {"sketch": [0, 0]}},
  {"click": {"sketch": [40, 30]}},
  {"expect": {"errors": 0}}
]

A new file in crates/ui-egui/tests/scenarios/ is picked up automatically. To record a bug before it's fixed, add a {"pending": "why"} step; its test is then ignored with that reason, and the fix removes the step.

CI profile

CI runs the tests with --profile ci: light optimisation, line tables, no LTO and debug assertions off. Some truck debug assertions fail on valid geometry; the ci profile disables them while building faster than --release. If a test fails only in a plain debug build, say so in the PR.

Run cargo xtask test to build with this profile and run the test binaries concurrently, with doc tests alongside. Arguments after -- go to each test binary, for example cargo xtask test -- shell. To run the test binaries sequentially instead, use cargo test --workspace --profile ci.