Test flatten_literal_params

README.md

@@ -40,6 +40,12 @@ Running `coverage html` and opening the document in the browser gives the follow
 
 Thijmen
 
+flatten_literal_params
+
+[commit](https://github.com/tthijm/sep/commit/2afde74ee94eb7e6cdc476356aa41f1ca09d87cf)
+
+![](./assets/flatten_literal_params_custom.png)
+
 \_human_join
 
 [commit](https://github.com/tthijm/sep/commit/88c98ebc05c4d67bcdce7d3046ffa786f79b9284)
@@ -70,6 +76,17 @@ Thijmen
 
 Thijmen
 
+test_flatten_literal_params
+
+[commit](https://github.com/tthijm/sep/commit/18e8104041610c32f9dedff6740688c4d1934550) + [commit](https://github.com/tthijm/sep/commit/138ca9a4c4b0a5f8fba254271f6b913b80d20b95)
+
+![](./assets/flatten_literal_params_before.png)
+
+![](./assets/flatten_literal_params_after.png)
+
+The coverage improvement is +100%.
+The coverage has been improved, because `flatten_literal_params` used to not be tested, while the new `test_flatten_literal_params` considers every branch to be taken.
+
 test\_\_human_join
 
 [commit](https://github.com/tthijm/sep/commit/92796db0afb5feff4b51b3c7e4874c2ba0eae7b9)

tests/test_utils.py

@@ -336,6 +336,21 @@ def test_format_dt(dt: datetime.datetime, style: typing.Optional[utils.Timestamp
     assert utils.format_dt(dt, style=style) == formatted
 
 
+@pytest.mark.parametrize(
+    ("parameters", "flattened"),
+    [
+        # Python 3.8: Literal[Literal[0]].__args__ == (Literal[0],)
+        # Python 3.x: Literal[Literal[0]].__args__ == (0,)
+        ([], ()),
+        ([0, 1, 2], (0, 1, 2)),
+        ([0, typing.Literal["a", 1], "b"], (0, "a", 1, "b")),
+        ([0, "a", typing.Literal[1, "b", 2], typing.Literal["c"]], (0, "a", 1, "b", 2, "c")),
+    ],
+)
+def test_flatten_literal_params(parameters: typing.Iterable[typing.Any], flattened: typing.Tuple[typing.Any, ...]) -> None:
+    assert utils.flatten_literal_params(parameters) == flattened
+
+
 def test__human_join() -> None:
     assert utils._human_join([]) == ""
     assert utils._human_join(["cat"]) == "cat"