Add tests for annotation helpers.

scrapy_zyte_api/_annotations.py

@@ -57,6 +57,7 @@ class _ActionResult(TypedDict, total=False):
 
 
 def make_hashable(obj: Any) -> Any:
+    """Converts input into hashable form, to use in ``Annotated``."""
     if isinstance(obj, (tuple, list)):
         return tuple((make_hashable(e) for e in obj))
 
@@ -67,6 +68,7 @@ def make_hashable(obj: Any) -> Any:
 
 
 def _from_hashable(obj: Any) -> Any:
+    """Converts a result of ``make_hashable`` back to original form."""
     if isinstance(obj, tuple):
         return [_from_hashable(o) for o in obj]
 

tests/test_annotations.py

@@ -0,0 +1,111 @@
+import pytest
+
+from scrapy_zyte_api._annotations import (
+    _from_hashable,
+    actions,
+    custom_attrs,
+    make_hashable,
+)
+
+
+@pytest.mark.parametrize(
+    "input,expected",
+    [
+        ([], ()),
+        (set(), ()),
+        ({}, frozenset()),
+        ("foo", "foo"),
+        (["foo"], ("foo",)),
+        (42, 42),
+        (
+            {"action": "foo", "id": "xx"},
+            frozenset({("action", "foo"), ("id", "xx")}),
+        ),
+        (
+            [{"action": "foo", "id": "xx"}, {"action": "bar"}],
+            (
+                frozenset({("action", "foo"), ("id", "xx")}),
+                frozenset({("action", "bar")}),
+            ),
+        ),
+        (
+            {"action": "foo", "options": {"a": "b", "c": ["d", "e"]}},
+            frozenset(
+                {
+                    ("action", "foo"),
+                    ("options", frozenset({("a", "b"), ("c", ("d", "e"))})),
+                }
+            ),
+        ),
+    ],
+)
+def test_make_hashable(input, expected):
+    assert make_hashable(input) == expected
+
+
+@pytest.mark.parametrize(
+    "input,expected",
+    [
+        ((), []),
+        (frozenset(), {}),
+        ("foo", "foo"),
+        (("foo",), ["foo"]),
+        (42, 42),
+        (
+            frozenset({("action", "foo"), ("id", "xx")}),
+            {"action": "foo", "id": "xx"},
+        ),
+        (
+            (
+                frozenset({("action", "foo"), ("id", "xx")}),
+                frozenset({("action", "bar")}),
+            ),
+            [{"action": "foo", "id": "xx"}, {"action": "bar"}],
+        ),
+        (
+            frozenset(
+                {
+                    ("action", "foo"),
+                    ("options", frozenset({("a", "b"), ("c", ("d", "e"))})),
+                }
+            ),
+            {"action": "foo", "options": {"a": "b", "c": ["d", "e"]}},
+        ),
+    ],
+)
+def test_from_hashable(input, expected):
+    assert _from_hashable(input) == expected
+
+
+@pytest.mark.parametrize(
+    "input,expected",
+    [
+        ([], ()),
+        ([{}], (frozenset(),)),
+        (
+            [{"action": "foo"}, {"action": "bar"}],
+            (
+                frozenset({("action", "foo")}),
+                frozenset({("action", "bar")}),
+            ),
+        ),
+    ],
+)
+def test_actions(input, expected):
+    assert actions(input) == expected
+
+
+@pytest.mark.parametrize(
+    "input,options,expected",
+    [
+        ({}, None, (frozenset(), None)),
+        ({"foo": "bar"}, None, (frozenset({("foo", "bar")}), None)),
+        (
+            {"foo": "bar"},
+            {"tokens": 42},
+            (frozenset({("foo", "bar")}), frozenset({("tokens", 42)})),
+        ),
+    ],
+)
+def test_custom_attrs(input, options, expected):
+    assert custom_attrs(input, options) == expected