Initial code commit

tests/conftest.py

@@ -0,0 +1,73 @@
+"""Shared test fixtures and a controllable fake command runner."""
+
+from __future__ import annotations
+
+from collections.abc import Callable, Iterable
+
+import pytest
+
+from schedls.errors import DependencyMissingError, OperationalError
+from schedls.runner import Completed
+
+
+class FakeRunner:
+    """A duck-typed stand-in for :class:`schedls.runner.CommandRunner`."""
+
+    def __init__(
+        self,
+        handlers: dict[str, Callable] | None = None,
+        available: Iterable[str] = (),
+    ) -> None:
+        self.handlers = handlers or {}
+        self.available = set(available)
+        self.calls: list[tuple[list[str], str, str | None]] = []
+
+    def has(self, name: str) -> bool:
+        return name in self.available
+
+    def resolve(self, name: str) -> str | None:
+        return name if name in self.available else None
+
+    def run(self, argv, *, env_policy="minimal", timeout=None, check=True, input_text=None):
+        args = list(argv)
+        self.calls.append((args, env_policy, input_text))
+        handler = self.handlers.get(args[0])
+        if handler is None:
+            if args[0] not in self.available:
+                raise DependencyMissingError(f"required command not found: {args[0]}")
+            completed = Completed(tuple(args), 0, "", "")
+        else:
+            completed = _coerce(args, handler(args, input_text))
+        if check and completed.returncode != 0:
+            raise OperationalError(
+                f"command failed ({completed.returncode}): {' '.join(args)}",
+                hint=completed.stderr or completed.stdout or None,
+            )
+        return completed
+
+    def try_run(self, argv, *, env_policy="minimal", timeout=None, input_text=None):
+        if argv[0] not in self.available and argv[0] not in self.handlers:
+            return None
+        try:
+            return self.run(argv, env_policy=env_policy, input_text=input_text)
+        except OperationalError:
+            return None
+
+
+def _coerce(args: list[str], result) -> Completed:
+    if isinstance(result, Completed):
+        return result
+    if isinstance(result, str):
+        return Completed(tuple(args), 0, result, "")
+    if isinstance(result, tuple):
+        if len(result) == 3:
+            return Completed(tuple(args), *result)
+        if len(result) == 2:
+            return Completed(tuple(args), 0, result[0], result[1])
+        raise TypeError(f"unsupported fake result: {result!r}")
+    raise TypeError(f"unsupported fake result: {result!r}")
+
+
+@pytest.fixture
+def fake_runner() -> FakeRunner:
+    return FakeRunner()