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fix doc generation
[etc/vim.git] / tests / test_black.py
index 53d175066a95e4e1e56d4f7ee2460fada0e9309b..66a0761ecf82a2d3c529fa0fff499bf932c2412f 100644 (file)
@@ -2,25 +2,15 @@
 import asyncio
 import logging
 from concurrent.futures import ThreadPoolExecutor
 import asyncio
 import logging
 from concurrent.futures import ThreadPoolExecutor
-from contextlib import contextmanager, redirect_stderr
-from functools import partial, wraps
+from contextlib import contextmanager
+from functools import partial
 from io import BytesIO, TextIOWrapper
 import os
 from pathlib import Path
 import re
 import sys
 from tempfile import TemporaryDirectory
 from io import BytesIO, TextIOWrapper
 import os
 from pathlib import Path
 import re
 import sys
 from tempfile import TemporaryDirectory
-from typing import (
-    Any,
-    BinaryIO,
-    Callable,
-    Coroutine,
-    Generator,
-    List,
-    Tuple,
-    Iterator,
-    TypeVar,
-)
+from typing import Any, BinaryIO, Generator, List, Tuple, Iterator, TypeVar
 import unittest
 from unittest.mock import patch, MagicMock
 
 import unittest
 from unittest.mock import patch, MagicMock
 
@@ -32,7 +22,8 @@ from black import Feature, TargetVersion
 
 try:
     import blackd
 
 try:
     import blackd
-    from aiohttp.test_utils import TestClient, TestServer
+    from aiohttp.test_utils import AioHTTPTestCase, unittest_run_loop
+    from aiohttp import web
 except ImportError:
     has_blackd_deps = False
 else:
 except ImportError:
     has_blackd_deps = False
 else:
@@ -90,25 +81,25 @@ def cache_dir(exists: bool = True) -> Iterator[Path]:
 @contextmanager
 def event_loop(close: bool) -> Iterator[None]:
     policy = asyncio.get_event_loop_policy()
 @contextmanager
 def event_loop(close: bool) -> Iterator[None]:
     policy = asyncio.get_event_loop_policy()
-    old_loop = policy.get_event_loop()
     loop = policy.new_event_loop()
     asyncio.set_event_loop(loop)
     try:
         yield
 
     finally:
     loop = policy.new_event_loop()
     asyncio.set_event_loop(loop)
     try:
         yield
 
     finally:
-        policy.set_event_loop(old_loop)
         if close:
             loop.close()
 
 
         if close:
             loop.close()
 
 
-def async_test(f: Callable[..., Coroutine[Any, None, R]]) -> Callable[..., None]:
-    @event_loop(close=True)
-    @wraps(f)
-    def wrapper(*args: Any, **kwargs: Any) -> None:
-        asyncio.get_event_loop().run_until_complete(f(*args, **kwargs))
-
-    return wrapper
+@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
 
 
 class BlackRunner(CliRunner):
 
 
 class BlackRunner(CliRunner):
@@ -264,6 +255,14 @@ class BlackTestCase(unittest.TestCase):
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
+    @patch("black.dump_to_file", dump_to_stderr)
+    def test_function_trailing_comma(self) -> None:
+        source, expected = read_data("function_trailing_comma")
+        actual = fs(source)
+        self.assertFormatEqual(expected, actual)
+        black.assert_equivalent(source, actual)
+        black.assert_stable(source, actual, black.FileMode())
+
     @patch("black.dump_to_file", dump_to_stderr)
     def test_expression(self) -> None:
         source, expected = read_data("expression")
     @patch("black.dump_to_file", dump_to_stderr)
     def test_expression(self) -> None:
         source, expected = read_data("expression")
@@ -272,6 +271,23 @@ class BlackTestCase(unittest.TestCase):
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
+    @patch("black.dump_to_file", dump_to_stderr)
+    def test_pep_572(self) -> None:
+        source, expected = read_data("pep_572")
+        actual = fs(source)
+        self.assertFormatEqual(expected, actual)
+        black.assert_stable(source, actual, black.FileMode())
+        if sys.version_info >= (3, 8):
+            black.assert_equivalent(source, actual)
+
+    def test_pep_572_version_detection(self) -> None:
+        source, _ = read_data("pep_572")
+        root = black.lib2to3_parse(source)
+        features = black.get_features_used(root)
+        self.assertIn(black.Feature.ASSIGNMENT_EXPRESSIONS, features)
+        versions = black.detect_target_versions(root)
+        self.assertIn(black.TargetVersion.PY38, versions)
+
     def test_expression_ff(self) -> None:
         source, expected = read_data("expression")
         tmp_file = Path(black.dump_to_file(source))
     def test_expression_ff(self) -> None:
         source, expected = read_data("expression")
         tmp_file = Path(black.dump_to_file(source))
@@ -319,6 +335,23 @@ class BlackTestCase(unittest.TestCase):
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
+    @patch("black.dump_to_file", dump_to_stderr)
+    def test_pep_570(self) -> None:
+        source, expected = read_data("pep_570")
+        actual = fs(source)
+        self.assertFormatEqual(expected, actual)
+        black.assert_stable(source, actual, black.FileMode())
+        if sys.version_info >= (3, 8):
+            black.assert_equivalent(source, actual)
+
+    def test_detect_pos_only_arguments(self) -> None:
+        source, _ = read_data("pep_570")
+        root = black.lib2to3_parse(source)
+        features = black.get_features_used(root)
+        self.assertIn(black.Feature.POS_ONLY_ARGUMENTS, features)
+        versions = black.detect_target_versions(root)
+        self.assertIn(black.TargetVersion.PY38, versions)
+
     @patch("black.dump_to_file", dump_to_stderr)
     def test_string_quotes(self) -> None:
         source, expected = read_data("string_quotes")
     @patch("black.dump_to_file", dump_to_stderr)
     def test_string_quotes(self) -> None:
         source, expected = read_data("string_quotes")
@@ -436,6 +469,14 @@ class BlackTestCase(unittest.TestCase):
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
+    @patch("black.dump_to_file", dump_to_stderr)
+    def test_remove_parens(self) -> None:
+        source, expected = read_data("remove_parens")
+        actual = fs(source)
+        self.assertFormatEqual(expected, actual)
+        black.assert_equivalent(source, actual)
+        black.assert_stable(source, actual, black.FileMode())
+
     @patch("black.dump_to_file", dump_to_stderr)
     def test_string_prefixes(self) -> None:
         source, expected = read_data("string_prefixes")
     @patch("black.dump_to_file", dump_to_stderr)
     def test_string_prefixes(self) -> None:
         source, expected = read_data("string_prefixes")
@@ -474,7 +515,7 @@ class BlackTestCase(unittest.TestCase):
         source, expected = read_data("python2")
         actual = fs(source)
         self.assertFormatEqual(expected, actual)
         source, expected = read_data("python2")
         actual = fs(source)
         self.assertFormatEqual(expected, actual)
-        black.assert_equivalent(source, actual)
+        black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
     @patch("black.dump_to_file", dump_to_stderr)
         black.assert_stable(source, actual, black.FileMode())
 
     @patch("black.dump_to_file", dump_to_stderr)
@@ -483,6 +524,7 @@ class BlackTestCase(unittest.TestCase):
         mode = black.FileMode(target_versions={TargetVersion.PY27})
         actual = fs(source, mode=mode)
         self.assertFormatEqual(expected, actual)
         mode = black.FileMode(target_versions={TargetVersion.PY27})
         actual = fs(source, mode=mode)
         self.assertFormatEqual(expected, actual)
+        black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, mode)
 
     @patch("black.dump_to_file", dump_to_stderr)
         black.assert_stable(source, actual, mode)
 
     @patch("black.dump_to_file", dump_to_stderr)
@@ -490,6 +532,7 @@ class BlackTestCase(unittest.TestCase):
         source, expected = read_data("python2_unicode_literals")
         actual = fs(source)
         self.assertFormatEqual(expected, actual)
         source, expected = read_data("python2_unicode_literals")
         actual = fs(source)
         self.assertFormatEqual(expected, actual)
+        black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
     @patch("black.dump_to_file", dump_to_stderr)
         black.assert_stable(source, actual, black.FileMode())
 
     @patch("black.dump_to_file", dump_to_stderr)
@@ -500,8 +543,24 @@ class BlackTestCase(unittest.TestCase):
         self.assertFormatEqual(expected, actual)
         black.assert_stable(source, actual, mode)
 
         self.assertFormatEqual(expected, actual)
         black.assert_stable(source, actual, mode)
 
+    @patch("black.dump_to_file", dump_to_stderr)
+    def test_async_as_identifier(self) -> None:
+        source_path = (THIS_DIR / "data" / "async_as_identifier.py").resolve()
+        source, expected = read_data("async_as_identifier")
+        actual = fs(source)
+        self.assertFormatEqual(expected, actual)
+        major, minor = sys.version_info[:2]
+        if major < 3 or (major <= 3 and minor < 7):
+            black.assert_equivalent(source, actual)
+        black.assert_stable(source, actual, black.FileMode())
+        # ensure black can parse this when the target is 3.6
+        self.invokeBlack([str(source_path), "--target-version", "py36"])
+        # but not on 3.7, because async/await is no longer an identifier
+        self.invokeBlack([str(source_path), "--target-version", "py37"], exit_code=123)
+
     @patch("black.dump_to_file", dump_to_stderr)
     def test_python37(self) -> None:
     @patch("black.dump_to_file", dump_to_stderr)
     def test_python37(self) -> None:
+        source_path = (THIS_DIR / "data" / "python37.py").resolve()
         source, expected = read_data("python37")
         actual = fs(source)
         self.assertFormatEqual(expected, actual)
         source, expected = read_data("python37")
         actual = fs(source)
         self.assertFormatEqual(expected, actual)
@@ -509,6 +568,10 @@ class BlackTestCase(unittest.TestCase):
         if major > 3 or (major == 3 and minor >= 7):
             black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
         if major > 3 or (major == 3 and minor >= 7):
             black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
+        # ensure black can parse this when the target is 3.7
+        self.invokeBlack([str(source_path), "--target-version", "py37"])
+        # but not on 3.6, because we use async as a reserved keyword
+        self.invokeBlack([str(source_path), "--target-version", "py36"], exit_code=123)
 
     @patch("black.dump_to_file", dump_to_stderr)
     def test_fmtonoff(self) -> None:
 
     @patch("black.dump_to_file", dump_to_stderr)
     def test_fmtonoff(self) -> None:
@@ -558,6 +621,14 @@ class BlackTestCase(unittest.TestCase):
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
         black.assert_equivalent(source, actual)
         black.assert_stable(source, actual, black.FileMode())
 
+    @patch("black.dump_to_file", dump_to_stderr)
+    def test_beginning_backslash(self) -> None:
+        source, expected = read_data("beginning_backslash")
+        actual = fs(source)
+        self.assertFormatEqual(expected, actual)
+        black.assert_equivalent(source, actual)
+        black.assert_stable(source, actual, black.FileMode())
+
     def test_tab_comment_indentation(self) -> None:
         contents_tab = "if 1:\n\tif 2:\n\t\tpass\n\t# comment\n\tpass\n"
         contents_spc = "if 1:\n    if 2:\n        pass\n    # comment\n    pass\n"
     def test_tab_comment_indentation(self) -> None:
         contents_tab = "if 1:\n\tif 2:\n\t\tpass\n\t# comment\n\tpass\n"
         contents_spc = "if 1:\n    if 2:\n        pass\n    # comment\n    pass\n"
@@ -970,10 +1041,10 @@ class BlackTestCase(unittest.TestCase):
         just_nl = "\n"
         with self.assertRaises(black.NothingChanged):
             black.format_file_contents(just_nl, mode=mode, fast=False)
         just_nl = "\n"
         with self.assertRaises(black.NothingChanged):
             black.format_file_contents(just_nl, mode=mode, fast=False)
-        same = "l = [1, 2, 3]\n"
+        same = "j = [1, 2, 3]\n"
         with self.assertRaises(black.NothingChanged):
             black.format_file_contents(same, mode=mode, fast=False)
         with self.assertRaises(black.NothingChanged):
             black.format_file_contents(same, mode=mode, fast=False)
-        different = "l = [1,2,3]"
+        different = "j = [1,2,3]"
         expected = same
         actual = black.format_file_contents(different, mode=mode, fast=False)
         self.assertEqual(expected, actual)
         expected = same
         actual = black.format_file_contents(different, mode=mode, fast=False)
         self.assertEqual(expected, actual)
@@ -1001,7 +1072,7 @@ class BlackTestCase(unittest.TestCase):
 
         with patch("black.out", out), patch("black.err", err):
             with self.assertRaises(AssertionError):
 
         with patch("black.out", out), patch("black.err", err):
             with self.assertRaises(AssertionError):
-                self.assertFormatEqual("l = [1, 2, 3]", "l = [1, 2, 3,]")
+                self.assertFormatEqual("j = [1, 2, 3]", "j = [1, 2, 3,]")
 
         out_str = "".join(out_lines)
         self.assertTrue("Expected tree:" in out_str)
 
         out_str = "".join(out_lines)
         self.assertTrue("Expected tree:" in out_str)
@@ -1443,97 +1514,102 @@ class BlackTestCase(unittest.TestCase):
             ff(THIS_FILE)
 
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
             ff(THIS_FILE)
 
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    def test_blackd_main(self) -> None:
+        with patch("blackd.web.run_app"):
+            result = CliRunner().invoke(blackd.main, [])
+            if result.exception is not None:
+                raise result.exception
+            self.assertEqual(result.exit_code, 0)
+
+
+class BlackDTestCase(AioHTTPTestCase):
+    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:
     async def test_blackd_request_needs_formatting(self) -> None:
-        app = blackd.make_app()
-        async with TestClient(TestServer(app)) as client:
-            response = await client.post("/", data=b"print('hello world')")
-            self.assertEqual(response.status, 200)
-            self.assertEqual(response.charset, "utf8")
-            self.assertEqual(await response.read(), b'print("hello world")\n')
+        response = await self.client.post("/", data=b"print('hello world')")
+        self.assertEqual(response.status, 200)
+        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.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    @unittest_run_loop
     async def test_blackd_request_no_change(self) -> None:
     async def test_blackd_request_no_change(self) -> None:
-        app = blackd.make_app()
-        async with TestClient(TestServer(app)) as client:
-            response = await client.post("/", data=b'print("hello world")\n')
-            self.assertEqual(response.status, 204)
-            self.assertEqual(await response.read(), b"")
+        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.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    @unittest_run_loop
     async def test_blackd_request_syntax_error(self) -> None:
     async def test_blackd_request_syntax_error(self) -> None:
-        app = blackd.make_app()
-        async with TestClient(TestServer(app)) as client:
-            response = await client.post("/", data=b"what even ( is")
-            self.assertEqual(response.status, 400)
-            content = await response.text()
-            self.assertTrue(
-                content.startswith("Cannot parse"),
-                msg=f"Expected error to start with 'Cannot parse', got {repr(content)}",
-            )
+        response = await self.client.post("/", data=b"what even ( is")
+        self.assertEqual(response.status, 400)
+        content = await response.text()
+        self.assertTrue(
+            content.startswith("Cannot parse"),
+            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.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    @unittest_run_loop
     async def test_blackd_unsupported_version(self) -> None:
     async def test_blackd_unsupported_version(self) -> None:
-        app = blackd.make_app()
-        async with TestClient(TestServer(app)) as client:
-            response = await client.post(
-                "/", data=b"what", headers={blackd.VERSION_HEADER: "2"}
-            )
-            self.assertEqual(response.status, 501)
+        response = await self.client.post(
+            "/", data=b"what", headers={blackd.VERSION_HEADER: "2"}
+        )
+        self.assertEqual(response.status, 501)
 
 
+    @skip_if_exception("ClientOSError")
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    @unittest_run_loop
     async def test_blackd_supported_version(self) -> None:
     async def test_blackd_supported_version(self) -> None:
-        app = blackd.make_app()
-        async with TestClient(TestServer(app)) as client:
-            response = await client.post(
-                "/", data=b"what", headers={blackd.VERSION_HEADER: "1"}
-            )
-            self.assertEqual(response.status, 200)
+        response = await self.client.post(
+            "/", data=b"what", headers={blackd.VERSION_HEADER: "1"}
+        )
+        self.assertEqual(response.status, 200)
 
 
+    @skip_if_exception("ClientOSError")
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    @unittest_run_loop
     async def test_blackd_invalid_python_variant(self) -> None:
     async def test_blackd_invalid_python_variant(self) -> None:
-        app = blackd.make_app()
-        async with TestClient(TestServer(app)) as client:
-
-            async def check(header_value: str, expected_status: int = 400) -> None:
-                response = await client.post(
-                    "/",
-                    data=b"what",
-                    headers={blackd.PYTHON_VARIANT_HEADER: header_value},
-                )
-                self.assertEqual(response.status, expected_status)
-
-            await check("lol")
-            await check("ruby3.5")
-            await check("pyi3.6")
-            await check("py1.5")
-            await check("2.8")
-            await check("py2.8")
-            await check("3.0")
-            await check("pypy3.0")
-            await check("jython3.4")
-
+        async def check(header_value: str, expected_status: int = 400) -> None:
+            response = await self.client.post(
+                "/", data=b"what", headers={blackd.PYTHON_VARIANT_HEADER: header_value}
+            )
+            self.assertEqual(response.status, expected_status)
+
+        await check("lol")
+        await check("ruby3.5")
+        await check("pyi3.6")
+        await check("py1.5")
+        await check("2.8")
+        await check("py2.8")
+        await check("3.0")
+        await check("pypy3.0")
+        await check("jython3.4")
+
+    @skip_if_exception("ClientOSError")
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    @unittest_run_loop
     async def test_blackd_pyi(self) -> None:
     async def test_blackd_pyi(self) -> None:
-        app = blackd.make_app()
-        async with TestClient(TestServer(app)) as client:
-            source, expected = read_data("stub.pyi")
-            response = await client.post(
-                "/", data=source, headers={blackd.PYTHON_VARIANT_HEADER: "pyi"}
-            )
-            self.assertEqual(response.status, 200)
-            self.assertEqual(await response.text(), expected)
+        source, expected = read_data("stub.pyi")
+        response = await self.client.post(
+            "/", data=source, headers={blackd.PYTHON_VARIANT_HEADER: "pyi"}
+        )
+        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.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    @unittest_run_loop
     async def test_blackd_python_variant(self) -> None:
     async def test_blackd_python_variant(self) -> None:
-        app = blackd.make_app()
         code = (
             "def f(\n"
             "    and_has_a_bunch_of,\n"
         code = (
             "def f(\n"
             "    and_has_a_bunch_of,\n"
@@ -1543,68 +1619,48 @@ class BlackTestCase(unittest.TestCase):
             "):\n"
             "    pass\n"
         )
             "):\n"
             "    pass\n"
         )
-        async with TestClient(TestServer(app)) as client:
-
-            async def check(header_value: str, expected_status: int) -> None:
-                response = await client.post(
-                    "/", data=code, headers={blackd.PYTHON_VARIANT_HEADER: header_value}
-                )
-                self.assertEqual(response.status, expected_status)
 
 
-            await check("3.6", 200)
-            await check("py3.6", 200)
-            await check("3.6,3.7", 200)
-            await check("3.6,py3.7", 200)
-
-            await check("2", 204)
-            await check("2.7", 204)
-            await check("py2.7", 204)
-            await check("3.4", 204)
-            await check("py3.4", 204)
-
-    @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
-    async def test_blackd_fast(self) -> None:
-        with open(os.devnull, "w") as dn, redirect_stderr(dn):
-            app = blackd.make_app()
-            async with TestClient(TestServer(app)) as client:
-                response = await client.post("/", data=b"ur'hello'")
-                self.assertEqual(response.status, 500)
-                self.assertIn("failed to parse source file", await response.text())
-                response = await client.post(
-                    "/", data=b"ur'hello'", headers={blackd.FAST_OR_SAFE_HEADER: "fast"}
-                )
-                self.assertEqual(response.status, 200)
+        async def check(header_value: str, expected_status: int) -> None:
+            response = await self.client.post(
+                "/", data=code, headers={blackd.PYTHON_VARIANT_HEADER: header_value}
+            )
+            self.assertEqual(
+                response.status, expected_status, msg=await response.text()
+            )
 
 
+        await check("3.6", 200)
+        await check("py3.6", 200)
+        await check("3.6,3.7", 200)
+        await check("3.6,py3.7", 200)
+        await check("py36,py37", 200)
+        await check("36", 200)
+        await check("3.6.4", 200)
+
+        await check("2", 204)
+        await check("2.7", 204)
+        await check("py2.7", 204)
+        await check("3.4", 204)
+        await check("py3.4", 204)
+        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.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    @unittest_run_loop
     async def test_blackd_line_length(self) -> None:
     async def test_blackd_line_length(self) -> None:
-        app = blackd.make_app()
-        async with TestClient(TestServer(app)) as client:
-            response = await client.post(
-                "/", data=b'print("hello")\n', headers={blackd.LINE_LENGTH_HEADER: "7"}
-            )
-            self.assertEqual(response.status, 200)
+        response = await self.client.post(
+            "/", data=b'print("hello")\n', headers={blackd.LINE_LENGTH_HEADER: "7"}
+        )
+        self.assertEqual(response.status, 200)
 
 
+    @skip_if_exception("ClientOSError")
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
     @unittest.skipUnless(has_blackd_deps, "blackd's dependencies are not installed")
-    @async_test
+    @unittest_run_loop
     async def test_blackd_invalid_line_length(self) -> None:
     async def test_blackd_invalid_line_length(self) -> None:
-        app = blackd.make_app()
-        async with TestClient(TestServer(app)) as client:
-            response = await client.post(
-                "/",
-                data=b'print("hello")\n',
-                headers={blackd.LINE_LENGTH_HEADER: "NaN"},
-            )
-            self.assertEqual(response.status, 400)
-
-    @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, [])
-            if result.exception is not None:
-                raise result.exception
-            self.assertEqual(result.exit_code, 0)
+        response = await self.client.post(
+            "/", data=b'print("hello")\n', headers={blackd.LINE_LENGTH_HEADER: "NaN"}
+        )
+        self.assertEqual(response.status, 400)
 
 
 if __name__ == "__main__":
 
 
 if __name__ == "__main__":