linting, more explicit coverage, add release notes

hypothesis-python/RELEASE.rst

@@ -0,0 +1,3 @@
+RELEASE_TYPE: patch
+
+This patch lays some groundwork for migrating our internal representation to the typed choice sequence (:issue:`3921`)

hypothesis-python/src/hypothesis/internal/conjecture/choice.py

@@ -204,21 +204,19 @@ def choice_to_index(choice, kwargs):
             return 0
         return int(choice)
     elif isinstance(choice, bytes):
-        index = collection_index(
+        return collection_index(
             list(choice),
             min_size=kwargs["min_size"],
             alphabet_size=2**8,
         )
-        return index
     elif isinstance(choice, str):
         intervals = kwargs["intervals"]
-        index = collection_index(
+        return collection_index(
             choice,
             min_size=kwargs["min_size"],
             alphabet_size=len(intervals),
             to_order=intervals.index_from_char_in_shrink_order,
         )
-        return index
     elif isinstance(choice, float):
         sign = int(sign_aware_lte(choice, -0.0))
         return (sign << 64) | float_to_lex(abs(choice))

hypothesis-python/tests/conjecture/test_ir.py

@@ -797,6 +797,8 @@ def test_choice_index_and_value_are_inverses(ir_type_and_kwargs):
         ("integer", integer_kw(max_value=5, shrink_towards=2), range(-10, 5 + 1)),
         ("integer", integer_kw(max_value=5), range(-10, 5 + 1)),
         ("integer", integer_kw(min_value=0, shrink_towards=1), range(10)),
+        ("integer", integer_kw(-5, 5, shrink_towards=3), range(-5, 5 + 1)),
+        ("integer", integer_kw(-5, 5, shrink_towards=-3), range(-5, 5 + 1)),
         (
             "float",
             float_kw(1.0, next_up(next_up(1.0))),