Pin black in CI

This temporarily fixes an incompatibility between black and darker

.github/workflows/python-package.yml

@@ -29,7 +29,7 b' jobs:'
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install darker
+        pip install darker black==21.12b0
     - name: Lint with darker
       run: |
         darker -r 60625f241f298b5039cb2debc365db38aa7bb522 --check --diff . || (

IPython/tests/cve.py

@@ -11,6 +11,7 b' import string'
 import subprocess
 import time
 
+
 def test_cve_2022_21699():
     """
     Here we test CVE-2022-21699.
@@ -23,34 +24,42 b' def test_cve_2022_21699():'
 
     """
 
-    dangerous_profile_dir = Path('profile_default')
+    dangerous_profile_dir = Path("profile_default")
 
-    dangerous_startup_dir = dangerous_profile_dir / 'startup'
-    dangerous_expected = 'CVE-2022-21699-'+''.join([random.choice(string.ascii_letters) for i in range(10)])
+    dangerous_startup_dir = dangerous_profile_dir / "startup"
+    dangerous_expected = "CVE-2022-21699-" + "".join(
+        [random.choice(string.ascii_letters) for i in range(10)]
+    )
 
     with TemporaryWorkingDirectory() as t:
         dangerous_startup_dir.mkdir(parents=True)
-        (dangerous_startup_dir/ 'foo.py').write_text(f'print("{dangerous_expected}")')
+        (dangerous_startup_dir / "foo.py").write_text(f'print("{dangerous_expected}")')
         # 1 sec to make sure FS is flushed.
         #time.sleep(1)
-        cmd = [sys.executable,'-m', 'IPython']
+        cmd = [sys.executable, "-m", "IPython"]
         env = os.environ.copy()
-        env['IPY_TEST_SIMPLE_PROMPT'] = '1'
-
+        env["IPY_TEST_SIMPLE_PROMPT"] = "1"
 
         # First we fake old behavior, making sure the profile is/was actually dangerous
-        p_dangerous = subprocess.Popen(cmd + [f'--profile-dir={dangerous_profile_dir}'], env=env, stdin=subprocess.PIPE,
-                stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        p_dangerous = subprocess.Popen(
+            cmd + [f"--profile-dir={dangerous_profile_dir}"],
+            env=env,
+            stdin=subprocess.PIPE,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+        )
         out_dangerous, err_dangerouns = p_dangerous.communicate(b"exit\r")
         assert dangerous_expected in out_dangerous.decode()
 
         # Now that we know it _would_ have been dangerous, we test it's not loaded
-        p = subprocess.Popen(cmd, env=env, stdin=subprocess.PIPE,
-                stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        p = subprocess.Popen(
+            cmd,
+            env=env,
+            stdin=subprocess.PIPE,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+        )
         out, err = p.communicate(b"exit\r")
-        assert b'IPython' in out
+        assert b"IPython" in out
         assert dangerous_expected not in out.decode()
-        assert err == b''
-
-
-
+        assert err == b""