metronome/tests/adapters/py_adapter.py
Me Here 754ed1c22d Formalize track format: spec + golden-vector conformance suite
Single source of truth for the track ("program"/"patch") grammar, which was
implemented by hand in src/engine.js and pico-cp/app.py with no cross-check and
had quietly drifted.

- docs/track-format.md: formal grammar, container (programs.json) schema with a
  version field, the new per-track playback-flow model (rep/end + relative goto;
  default = loop forever), normalization rules, and a list of known divergences.
- tests/: golden vectors + a runner that loads the REAL engine.js and app.py
  grammar (no copies; app.py via ast extraction) and compares both against the
  spec. Exit non-zero on unexpected mismatch or round-trip break -> usable as CI.

Surfaces real divergences for follow-up: default accent pattern (no =pattern)
differs web vs device and affects shipped presets; euclid not parsed on device;
vol/cd dropped on device; unknown-sound fallback; tempo clamp; empty patch.
The rep/end playback-flow vectors are the acceptance test for building that.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-05-30 23:54:20 -05:00

93 lines
3 KiB
Python

#!/usr/bin/env python3
"""Python adapter: extracts the REAL grammar functions out of pico-cp/app.py (no copy) and
emits the neutral normalized structure from docs/track-format.md §5.
app.py can't be imported directly (it does hardware init at module load), so we pull just the
pure codec nodes by name via `ast` and exec them in isolation. This tests the actual firmware
code and survives edits as long as the function/constant names persist.
"""
import ast
import json
import os
import sys
APP = os.path.join(os.path.dirname(__file__), "..", "..", "pico-cp", "app.py")
WANT = {"PAT", "PRIO", "PAT_CH", "parse_program", "_parse_lane", "lane_to_str"}
with open(APP) as f:
_src = f.read()
_segs = []
for node in ast.parse(_src).body:
name = None
if isinstance(node, ast.Assign) and len(node.targets) == 1 and isinstance(node.targets[0], ast.Name):
name = node.targets[0].id
elif isinstance(node, ast.FunctionDef):
name = node.name
if name in WANT:
_segs.append(ast.get_source_segment(_src, node))
NS = {}
exec("\n".join(_segs), NS)
def _prog_str(bpm, lanes, bars, ramp, trainer):
# Mirrors app.py App._prog_str (app.py:577) using the real lane_to_str.
parts = ["t" + str(bpm)]
if bars:
parts.append("b" + str(bars))
if ramp:
parts.append("rmp%d/%d/%d" % (ramp.get("start", bpm), ramp["amt"], ramp["every"]))
if trainer:
parts.append("tr%d/%d" % (trainer["play"], trainer["mute"]))
for L in lanes:
parts.append(NS["lane_to_str"](L))
return ";".join(parts)
def _gain_db(g):
if not g:
return 0
try:
return float(str(g).lstrip("@"))
except ValueError:
return 0
def normalize(patch):
bpm, lanes, bars, ramp, trainer = NS["parse_program"](patch)
return {
"bpm": bpm,
"bars": bars,
"volume": None, # device has no master-volume token
"countMs": 0, # device has no count-in
"ramp": {"start": ramp.get("start", bpm), "amt": ramp["amt"], "every": ramp["every"]} if ramp else None,
"trainer": {"play": trainer["play"], "mute": trainer["mute"]} if trainer else None,
"rep": None, # not parsed yet
"end": None, # not parsed yet
"lanes": [
{
"sound": L["sound"],
"groups": list(L.get("groups", [4])),
"sub": L["sub"],
"swing": bool(L["swing"]),
"poly": bool(L["poly"]),
"mute": bool(L["mute"]),
"gainDb": _gain_db(L.get("gain", "")),
"levels": [int(v) for v in L["levels"]],
}
for L in lanes
],
}
def canonical(patch):
return _prog_str(*NS["parse_program"](patch))
if __name__ == "__main__":
patch = sys.argv[1] if len(sys.argv) > 1 else ""
# Re-parse the canonical form too, so the runner can check idempotency in one call.
c1 = canonical(patch)
c2 = canonical(c1)
sys.stdout.write(json.dumps({"norm": normalize(patch), "canonical": c1, "idempotent": c1 == c2}))