Merge the two test_identifiers.py files.

I created one in the wrong directory and didn't see the existing one.

---

Migrated from D4075 (view on Phabricator)

swh/model/tests/test_identifiers.py

@@ -1075,3 +1075,69 @@ TS_DICTS_INVALID_TIMESTAMP = [
 def test_normalize_timestamp_dict_invalid_timestamp(dict_input):
     with pytest.raises(ValueError, match="non-integer timestamp"):
         normalize_timestamp(dict_input)
+
+
+def test_swhid_hash():
+    object_id = "94a9ed024d3859793618152ea559a168bbcbb5e2"
+
+    assert hash(SWHID(object_type="directory", object_id=object_id)) == hash(
+        SWHID(object_type="directory", object_id=object_id)
+    )
+
+    assert hash(
+        SWHID(
+            object_type="directory",
+            object_id=object_id,
+            metadata={"foo": "bar", "baz": "qux"},
+        )
+    ) == hash(
+        SWHID(
+            object_type="directory",
+            object_id=object_id,
+            metadata={"foo": "bar", "baz": "qux"},
+        )
+    )
+
+    # Different order of the dictionary, so the underlying order of the tuple in
+    # ImmutableDict is different.
+    assert hash(
+        SWHID(
+            object_type="directory",
+            object_id=object_id,
+            metadata={"foo": "bar", "baz": "qux"},
+        )
+    ) == hash(
+        SWHID(
+            object_type="directory",
+            object_id=object_id,
+            metadata={"baz": "qux", "foo": "bar"},
+        )
+    )
+
+
+def test_swhid_eq():
+    object_id = "94a9ed024d3859793618152ea559a168bbcbb5e2"
+
+    assert SWHID(object_type="directory", object_id=object_id) == SWHID(
+        object_type="directory", object_id=object_id
+    )
+
+    assert SWHID(
+        object_type="directory",
+        object_id=object_id,
+        metadata={"foo": "bar", "baz": "qux"},
+    ) == SWHID(
+        object_type="directory",
+        object_id=object_id,
+        metadata={"foo": "bar", "baz": "qux"},
+    )
+
+    assert SWHID(
+        object_type="directory",
+        object_id=object_id,
+        metadata={"foo": "bar", "baz": "qux"},
+    ) == SWHID(
+        object_type="directory",
+        object_id=object_id,
+        metadata={"baz": "qux", "foo": "bar"},
+    )