Mark blackd tests with the blackd optional marker (#2204)

This is a follow-up of #2203 that uses a pytest marker instead of a bunch of
`skipUnless`.  Similarly to the Python 2 tests, they are running by default and
will crash on an unsuspecting contributor with missing dependencies.  This is
by design, we WANT contributors to test everything.  Unless we actually don't
and then we can run:

  pytest --run-optional=no_blackd

Relatedly, bump required aiohttp to 3.6.0 at least to get rid of expected
failures on Python 3.8 (see 6b5eb7d465).

Pipfile

@@ -20,7 +20,7 @@ wheel = ">=0.31.1"
 black = {editable = true, extras = ["d"], path = "."}
 
 [packages]
-aiohttp = ">=3.3.2"
+aiohttp = ">=3.6.0"
 aiohttp-cors = "*"
 appdirs = "*"
 click = ">=7.1.2"

pyproject.toml

@@ -30,4 +30,5 @@ build-backend = "setuptools.build_meta"
 # Option below requires `tests/optional.py`
 optional-tests = [
   "no_python2: run when `python2` extra NOT installed",
+  "no_blackd: run when `d` extra NOT installed",
 ]

setup.py

@@ -83,7 +83,7 @@ def get_long_description() -> str:
         "mypy_extensions>=0.4.3",
     ],
     extras_require={
-        "d": ["aiohttp>=3.3.2", "aiohttp-cors"],
+        "d": ["aiohttp>=3.6.0", "aiohttp-cors"],
         "colorama": ["colorama>=0.4.3"],
         "python2": ["typed-ast>=1.4.2"],
     },

tests/test_blackd.py

@@ -1,10 +1,10 @@
 import re
-import unittest
 from unittest.mock import patch
 
 from click.testing import CliRunner
+import pytest
 
-from tests.util import read_data, DETERMINISTIC_HEADER, skip_if_exception
+from tests.util import read_data, DETERMINISTIC_HEADER
 
 try:
     import blackd
@@ -16,8 +16,8 @@
     has_blackd_deps = True
 
 
+@pytest.mark.blackd
 class BlackDTestCase(AioHTTPTestCase):
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     def test_blackd_main(self) -> None:
         with patch("blackd.web.run_app"):
             result = CliRunner().invoke(blackd.main, [])
@@ -28,10 +28,6 @@ def test_blackd_main(self) -> None:
     async def get_application(self) -> web.Application:
         return blackd.make_app()
 
-    # TODO: remove these decorators once the below is released
-    # https://github.com/aio-libs/aiohttp/pull/3727
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_request_needs_formatting(self) -> None:
         response = await self.client.post("/", data=b"print('hello world')")
@@ -39,16 +35,12 @@ async def test_blackd_request_needs_formatting(self) -> None:
         self.assertEqual(response.charset, "utf8")
         self.assertEqual(await response.read(), b'print("hello world")\n')
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_request_no_change(self) -> None:
         response = await self.client.post("/", data=b'print("hello world")\n')
         self.assertEqual(response.status, 204)
         self.assertEqual(await response.read(), b"")
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_request_syntax_error(self) -> None:
         response = await self.client.post("/", data=b"what even ( is")
@@ -59,8 +51,6 @@ async def test_blackd_request_syntax_error(self) -> None:
             msg=f"Expected error to start with 'Cannot parse', got {repr(content)}",
         )
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_unsupported_version(self) -> None:
         response = await self.client.post(
@@ -68,8 +58,6 @@ async def test_blackd_unsupported_version(self) -> None:
         )
         self.assertEqual(response.status, 501)
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_supported_version(self) -> None:
         response = await self.client.post(
@@ -77,8 +65,6 @@ async def test_blackd_supported_version(self) -> None:
         )
         self.assertEqual(response.status, 200)
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_invalid_python_variant(self) -> None:
         async def check(header_value: str, expected_status: int = 400) -> None:
@@ -97,8 +83,6 @@ async def check(header_value: str, expected_status: int = 400) -> None:
         await check("pypy3.0")
         await check("jython3.4")
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_pyi(self) -> None:
         source, expected = read_data("stub.pyi")
@@ -108,8 +92,6 @@ async def test_blackd_pyi(self) -> None:
         self.assertEqual(response.status, 200)
         self.assertEqual(await response.text(), expected)
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_diff(self) -> None:
         diff_header = re.compile(
@@ -128,8 +110,6 @@ async def test_blackd_diff(self) -> None:
         actual = diff_header.sub(DETERMINISTIC_HEADER, actual)
         self.assertEqual(actual, expected)
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_python_variant(self) -> None:
         code = (
@@ -166,8 +146,6 @@ async def check(header_value: str, expected_status: int) -> None:
         await check("py34,py36", 204)
         await check("34", 204)
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_line_length(self) -> None:
         response = await self.client.post(
@@ -175,8 +153,6 @@ async def test_blackd_line_length(self) -> None:
         )
         self.assertEqual(response.status, 200)
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_invalid_line_length(self) -> None:
         response = await self.client.post(
@@ -184,8 +160,6 @@ async def test_blackd_invalid_line_length(self) -> None:
         )
         self.assertEqual(response.status, 400)
 
-    @skip_if_exception("ClientOSError")
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest_run_loop
     async def test_blackd_response_black_version_header(self) -> None:
         response = await self.client.post("/")

tests/util.py

@@ -1,8 +1,7 @@
 import os
 import unittest
-from contextlib import contextmanager
 from pathlib import Path
-from typing import List, Tuple, Iterator, Any
+from typing import List, Tuple, Any
 import black
 from functools import partial
 
@@ -45,17 +44,6 @@ def assertFormatEqual(self, expected: str, actual: str) -> None:
         self.assertMultiLineEqual(expected, actual)
 
 
-@contextmanager
-def skip_if_exception(e: str) -> Iterator[None]:
-    try:
-        yield
-    except Exception as exc:
-        if exc.__class__.__name__ == e:
-            unittest.skip(f"Encountered expected exception {exc}, skipping")
-        else:
-            raise
-
-
 def read_data(name: str, data: bool = True) -> Tuple[str, str]:
     """read_data('test_name') -> 'input', 'output'"""
     if not name.endswith((".py", ".pyi", ".out", ".diff")):