require-subclass option now doesn't flag protocol classes (#130)

.github/workflows/build.yml

@@ -25,7 +25,7 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install tox tox-gh-actions poetry
+        pip install tox tox-gh-actions poetry==1.2.2
     - name: Test with tox
       run: tox
 

CHANGELOG.rst

@@ -1,6 +1,12 @@
 Changelog
 =========
 
+0.16.2 (2022-12-29)
+-------------------
+
+- Don't flag ``Protocol`` classes as needing slots if strict
+  ``require-subclass`` option is enabled.
+
 0.16.1 (2022-11-21)
 -------------------
 

docs/advanced.rst

@@ -18,7 +18,7 @@ Use the following configuration:
 
    repos:
    - repo: https://github.com/ariebovenberg/slotscheck
-     rev: v0.16.1
+     rev: v0.16.2
      hooks:
      - id: slotscheck
        # If your Python files are not importable from the project root,

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "slotscheck"
-version = "0.16.1"
+version = "0.16.2"
 description = "Ensure your __slots__ are working properly."
 authors = ["Arie Bovenberg <a.c.bovenberg@gmail.com>"]
 license = "MIT"
@@ -24,9 +24,8 @@ homepage = "https://github.com/ariebovenberg/slotscheck"
 
 [tool.poetry.dependencies]
 python = ">=3.7,<4"
-importlib-metadata = {version = ">=1,<5", python = "<3.8"}
+importlib-metadata = {version = ">=1,<6", python = "<3.8"}
 typing-extensions = {version = ">=4.1,<5", python = "<3.10"}
-dataclasses = {version = ">=0.6", python = "<3.7"}
 click = "^8.0"
 tomli = ">=0.2.6,<3.0.0"
 

src/slotscheck/cli.py

@@ -19,6 +19,7 @@
 )
 
 import click
+from typing_extensions import Protocol
 
 from . import config
 from .checks import (
@@ -560,7 +561,12 @@ def slot_messages(
         yield DuplicateSlots(c)
     if require_superclass and has_slots(c) and has_slotless_base(c):
         yield BadSlotInheritance(c)
-    elif require_subclass and not has_slots(c) and not has_slotless_base(c):
+    elif (
+        require_subclass
+        and not has_slots(c)
+        and not has_slotless_base(c)
+        and Protocol not in c.__bases__
+    ):
         yield ShouldHaveSlots(c)
 
 

tests/examples/module_not_ok/foo.py

@@ -1,3 +1,6 @@
+from typing_extensions import Protocol
+
+
 class A:
     pass
 
@@ -93,8 +96,16 @@ class X(RuntimeError):
 
 
 class Z:
-    __slots__ = ('a', 'b', 'c', 'b', 'b', 'c')
+    __slots__ = ("a", "b", "c", "b", "b", "c")
 
 
 class Za(Z):
-    __slots__ = ('b', 'c')
+    __slots__ = ("b", "c")
+
+
+class MyProto(Protocol):
+    pass
+
+
+class Zb(MyProto):
+    __slots__ = ()

tests/src/test_cli.py

@@ -205,8 +205,9 @@ def test_errors_with_default_settings(runner: CliRunner):
 ERROR: 'module_not_ok.foo:W' defines overlapping slots.
 ERROR: 'module_not_ok.foo:Z' has duplicate slots.
 ERROR: 'module_not_ok.foo:Za' defines overlapping slots.
+ERROR: 'module_not_ok.foo:Zb' has slots but superclass does not.
 Oh no, found some problems!
-Scanned 4 module(s), 28 class(es).
+Scanned 4 module(s), 30 class(es).
 """
     )
 
@@ -231,8 +232,9 @@ def test_errors_require_slots_subclass(runner: CliRunner):
 ERROR: 'module_not_ok.foo:W' defines overlapping slots.
 ERROR: 'module_not_ok.foo:Z' has duplicate slots.
 ERROR: 'module_not_ok.foo:Za' defines overlapping slots.
+ERROR: 'module_not_ok.foo:Zb' has slots but superclass does not.
 Oh no, found some problems!
-Scanned 4 module(s), 28 class(es).
+Scanned 4 module(s), 30 class(es).
 """
     )
 
@@ -255,8 +257,9 @@ def test_errors_disallow_nonslot_inherit(runner: CliRunner):
 ERROR: 'module_not_ok.foo:W' defines overlapping slots.
 ERROR: 'module_not_ok.foo:Z' has duplicate slots.
 ERROR: 'module_not_ok.foo:Za' defines overlapping slots.
+ERROR: 'module_not_ok.foo:Zb' has slots but superclass does not.
 Oh no, found some problems!
-Scanned 4 module(s), 28 class(es).
+Scanned 4 module(s), 30 class(es).
 """
     )
 
@@ -276,7 +279,7 @@ def test_errors_no_require_superclass(runner: CliRunner):
 ERROR: 'module_not_ok.foo:Z' has duplicate slots.
 ERROR: 'module_not_ok.foo:Za' defines overlapping slots.
 Oh no, found some problems!
-Scanned 4 module(s), 28 class(es).
+Scanned 4 module(s), 30 class(es).
 """
     )
 
@@ -297,8 +300,9 @@ def test_errors_with_exclude_classes(runner: CliRunner):
 ERROR: 'module_not_ok.foo:U.Ub' defines overlapping slots.
 ERROR: 'module_not_ok.foo:Z' has duplicate slots.
 ERROR: 'module_not_ok.foo:Za' defines overlapping slots.
+ERROR: 'module_not_ok.foo:Zb' has slots but superclass does not.
 Oh no, found some problems!
-Scanned 4 module(s), 28 class(es).
+Scanned 4 module(s), 30 class(es).
 """
     )
 
@@ -318,7 +322,7 @@ def test_errors_with_include_classes(runner: CliRunner):
 ERROR: 'module_not_ok.foo:W' defines overlapping slots.
 ERROR: 'module_not_ok.foo:Za' defines overlapping slots.
 Oh no, found some problems!
-Scanned 4 module(s), 28 class(es).
+Scanned 4 module(s), 30 class(es).
 """
     )
 
@@ -403,16 +407,19 @@ def test_module_not_ok_verbose(runner: CliRunner):
        Slots already defined in superclass:
        - 'b' (module_not_ok.foo:Z)
        - 'c' (module_not_ok.foo:Z)
+ERROR: 'module_not_ok.foo:Zb' has slots but superclass does not.
+       Superclasses without slots:
+       - 'module_not_ok.foo:MyProto'
 Oh no, found some problems!
 stats:
   modules:     4
     checked:   4
     excluded:  0
     skipped:   0
 
-  classes:     28
-    has slots: 21
-    no slots:  7
+  classes:     30
+    has slots: 22
+    no slots:  8
     n/a:       0
 """
     )
@@ -512,7 +519,7 @@ def test_finds_config(runner: CliRunner, mocker, tmpdir):
 ERROR: 'module_not_ok.foo:Z' has duplicate slots.
 ERROR: 'module_not_ok.foo:Za' defines overlapping slots.
 Oh no, found some problems!
-Scanned 4 module(s), 28 class(es).
+Scanned 4 module(s), 30 class(es).
 """
     )
 
@@ -541,7 +548,7 @@ def test_given_config(runner: CliRunner, tmpdir):
 ERROR: 'module_not_ok.foo:Z' has duplicate slots.
 ERROR: 'module_not_ok.foo:Za' defines overlapping slots.
 Oh no, found some problems!
-Scanned 4 module(s), 28 class(es).
+Scanned 4 module(s), 30 class(es).
 """
     )
 

tox.ini

@@ -3,7 +3,7 @@ isolated_build = true
 envlist = py{37,38,39,310,311},lint,mypy,isort,slots
 
 [testenv]
-whitelist_externals = 
+allowlist_externals = 
   poetry
 commands_pre=
     poetry install -n -v --no-root