The bpy.ops.export_scene.fbx argument block was duplicated in six scripts (hero, block frontage, north buildings, site, scale test, MPFB character) and all six carried mesh_smooth_type="OFF", which drops smoothing groups and made every Unreal import warn and every round part faceted. Tools/fbx_export_preset.py now owns the presets: - preset_kwargs(preset, selection, **overrides) is bpy-free and unit-tested; - export_static()/export_character() are thin wrappers that import bpy lazily; - ue_metric_v1 and ue_character_v1 keep the recorded scale contract (FBX_SCALE_NONE, apply_unit_scale, -Y forward / Z up) and use FACE smoothing. Callers switched: hero_facade_build, export_block_frontage, export_north_buildings, scale_test_export, mpfb_character_export, Art/blender/site/export_site_fbx. Verified by re-exporting every asset through the preset and re-importing all of them: 0 smoothing warnings on site, frontage and north buildings; packaging and -qaselftest all PASS (walk, transect 0 holes, wall probe 0/35, facade probe 0/9). 49 tool tests pass (9 new for the preset contract).
Tooling tests
Standard-library unittest tests for the host-side tools in Tools/. They never start Blender, Unreal, or the game; anything that needs those processes is verified by the tool itself and recorded in Docs/release-checks.md instead.
Run from the repository root:
python3 -m pip install -r requirements-tools.txt
python3 -m unittest discover -s Tools/tests -t Tools -p 'test_*.py'
The -t Tools top-level directory is required: the tests import the tool modules by their plain names (import input_emulation), which is why Tools/tests/ carries an __init__.py.
Individual test:
python3 -m unittest Tools.tests.test_input_emulation -v
What belongs here
Test the pure parts — argument parsing, key/coordinate encoding, geometry maths, licence gating, report formatting, decision classification. Network, Blender and Unreal calls stay out: a test that needs a paid API, a display, or an engine process is a manual check, not a unit test.
When a tool's logic is buried in main(), extract it into a function so it can be tested directly. That is a tooling improvement, not test scaffolding.
Geo (Geo/tools/) and Blender (Art/blender/*/) builders are tested the same way once their pure parts are extracted; note the module path in the test.