Seeded repo with intent and initial content.

tests/fixture_loading.py

@@ -0,0 +1,59 @@
+"""Shared fixture loading for the envelope tests.
+
+Fixture files are data (YAML). These helpers only load and merge them; all policy
+logic lives in the library under test.
+"""
+
+from __future__ import annotations
+
+import copy
+from pathlib import Path
+from typing import Any
+
+import pytest
+import yaml
+
+ROOT = Path(__file__).resolve().parent.parent
+ENVELOPES = ROOT / "envelopes"
+FIXTURES = Path(__file__).resolve().parent / "fixtures"
+
+DELETE = "~delete"
+
+
+def load_yaml(path: Path) -> Any:
+    with path.open(encoding="utf-8") as handle:
+        return yaml.safe_load(handle)
+
+
+def deep_merge(base: Any, patch: Any) -> Any:
+    """Return base with patch merged in; dicts merge recursively, '~delete' removes a key."""
+    if not isinstance(base, dict) or not isinstance(patch, dict):
+        return copy.deepcopy(patch)
+    merged = copy.deepcopy(base)
+    for key, value in patch.items():
+        if value == DELETE:
+            merged.pop(key, None)
+        elif key in merged:
+            merged[key] = deep_merge(merged[key], value)
+        else:
+            merged[key] = copy.deepcopy(value)
+    return merged
+
+
+def decision_cases() -> list[pytest.param]:
+    """All decision cases from fixtures/decisions/*.yaml, with file context merged per case."""
+    params = []
+    for path in sorted((FIXTURES / "decisions").glob("*.yaml")):
+        document = load_yaml(path)
+        file_context = document.get("context", {})
+        default_request = document.get("defaults", {}).get("request", {})
+        for case in document["cases"]:
+            params.append(
+                pytest.param(
+                    deep_merge(default_request, case["request"]),
+                    {**file_context, **case.get("context", {})},
+                    case["expect"],
+                    id=f"{path.stem}: {case['name']}",
+                )
+            )
+    return params