lf_mri_platform/services/seq-interp/tests/conftest.py

"""
Shared pytest fixtures and import setup for the seq_interp test suite.

The source modules import themselves as ``seq_interp.src...`` — the name the
Docker image mounts the tree under (``COPY services/seq-interp /app/seq_interp``).
Locally the directory is ``seq-interp`` (with a hyphen), which is not a valid
module name, so we register an in-process alias package ``seq_interp`` that
points at the service root. This lets tests import the real source unchanged.
"""
from __future__ import annotations

import pathlib
import sys
import types

import pytest

SERVICE_ROOT = pathlib.Path(__file__).resolve().parents[1]  # .../services/seq-interp

if "seq_interp" not in sys.modules:
    _pkg = types.ModuleType("seq_interp")
    _pkg.__path__ = [str(SERVICE_ROOT)]
    sys.modules["seq_interp"] = _pkg


class FakeSeq:
    """
    Minimal stand-in for a loaded pypulseq sequence, exposing only what
    ``Synchronizer.process`` touches: ``block_events`` and ``block_durations``.

    block_events layout (1-indexed, pypulseq order):
        [ ?, RF, GX, GY, GZ, ADC, EXT ]
          0   1   2   3   4   5    6
    """

    def __init__(self, specs: list[dict]):
        self.block_events: dict[int, list[int]] = {}
        self.block_durations: dict[int, float] = {}
        for i, spec in enumerate(specs, start=1):
            ev = [0, 0, 0, 0, 0, 0, 0]
            if spec.get("rf"):
                ev[1] = 1
            if spec.get("adc"):
                ev[5] = 1
            self.block_events[i] = ev
            self.block_durations[i] = spec["dur"]


@pytest.fixture
def make_seq():
    """Factory: make_seq([{"rf": bool, "adc": bool, "dur": seconds}, ...])."""
    return FakeSeq