diff --git a/share/tools/deroff.py b/share/tools/deroff.py
index 7178adc27..1f7017901 100755
--- a/share/tools/deroff.py
+++ b/share/tools/deroff.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-""" Deroff.py, ported to Python from the venerable deroff.c """
+"""Deroff.py, ported to Python from the venerable deroff.c"""
 
 import sys, re, string
 
diff --git a/tests/littlecheck.py b/tests/littlecheck.py
index 5ae44c667..8c025e20b 100755
--- a/tests/littlecheck.py
+++ b/tests/littlecheck.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 
-""" Command line test driver. """
+"""Command line test driver."""
 
 from __future__ import unicode_literals
 from __future__ import print_function
@@ -36,6 +36,7 @@ VARIABLE_OVERRIDE_RE = re.compile(r"\w+=.*")
 
 SKIP = object()
 
+
 def find_command(program):
     import os
 
@@ -49,6 +50,7 @@ def find_command(program):
 
     return None
 
+
 class Config(object):
     def __init__(self):
         # Whether to have verbose output.
@@ -59,7 +61,7 @@ class Config(object):
         self.progress = False
 
     def colors(self):
-        """ Return a dictionary mapping color names to ANSI escapes """
+        """Return a dictionary mapping color names to ANSI escapes"""
 
         def ansic(n):
             return "\033[%dm" % n if self.colorize else ""
@@ -130,7 +132,7 @@ class CheckerError(Exception):
 
 
 class Line(object):
-    """ A line that remembers where it came from. """
+    """A line that remembers where it came from."""
 
     def __init__(self, text, number, file):
         self.text = text
@@ -158,7 +160,7 @@ class Line(object):
         raise NotImplementedError
 
     def subline(self, text):
-        """ Return a substring of our line with the given text, preserving number and file. """
+        """Return a substring of our line with the given text, preserving number and file."""
         return Line(text, self.number, self.file)
 
     @staticmethod
@@ -230,7 +232,7 @@ class TestFailure(object):
         if self.signal:
             fmtstrs += [
                 "  Process was killed by signal {BOLD}" + self.signal + "{RESET}",
-                ""
+                "",
             ]
         if self.line and self.check:
             fmtstrs += [
@@ -351,7 +353,7 @@ class TestFailure(object):
         return "\n".join(fmtstrs).format(**fields)
 
     def print_message(self):
-        """ Print our message to stdout. """
+        """Print our message to stdout."""
         print(self.message())
 
 
@@ -381,7 +383,7 @@ def perform_substitution(input_str, subs):
 
 
 def runproc(cmd):
-    """ Wrapper around subprocess.Popen to save typing """
+    """Wrapper around subprocess.Popen to save typing"""
     PIPE = subprocess.PIPE
     proc = subprocess.Popen(
         cmd,
@@ -446,7 +448,7 @@ class TestRun(object):
         # SCREENFULS of text.
         # So we truncate the check list.
         if len(usedchecks) > len(usedlines):
-            usedchecks = usedchecks[:len(usedlines) + 5]
+            usedchecks = usedchecks[: len(usedlines) + 5]
 
         # Do a SequenceMatch! This gives us a diff-like thing.
         diff = SequenceMatcher(a=usedlines, b=usedchecks, autojunk=False)
@@ -474,13 +476,16 @@ class TestRun(object):
             return None
 
     def run(self):
-        """ Run the command. Return a TestFailure, or None. """
+        """Run the command. Return a TestFailure, or None."""
 
         def split_by_newlines(s):
             """Decode a string and split it by newlines only,
             retaining the newlines.
             """
-            return [s + "\n" for s in s.decode("utf-8", errors="backslashreplace").split("\n")]
+            return [
+                s + "\n"
+                for s in s.decode("utf-8", errors="backslashreplace").split("\n")
+            ]
 
         if self.config.verbose:
             print(self.subbed_command)
@@ -491,7 +496,13 @@ class TestRun(object):
         # most likely when the last command in a shell script doesn't exist.
         # So we check if the command *we execute* exists, and complain then.
         status = proc.returncode
-        cmd = next((word for word in shlex.split(self.subbed_command) if not VARIABLE_OVERRIDE_RE.match(word)))
+        cmd = next(
+            (
+                word
+                for word in shlex.split(self.subbed_command)
+                if not VARIABLE_OVERRIDE_RE.match(word)
+            )
+        )
         if status == 127 and not find_command(cmd):
             raise CheckerError("Command could not be found: " + cmd)
         if status == 126 and not find_command(cmd):
@@ -522,6 +533,7 @@ class TestRun(object):
             # Process was killed by a signal and failed,
             # add a message.
             import signal
+
             # Unfortunately strsignal only exists in python 3.8+,
             # and signal.signals is 3.5+.
             if hasattr(signal, "Signals"):
@@ -624,6 +636,7 @@ class CheckCmd(object):
 class Checker(object):
     def __init__(self, name, lines):
         self.name = name
+
         # Helper to yield subline containing group1 from all matching lines.
         def group1s(regex):
             for line in lines:
@@ -656,7 +669,7 @@ class Checker(object):
 
 
 def check_file(input_file, name, subs, config, failure_handler):
-    """ Check a single file. Return a True on success, False on error. """
+    """Check a single file. Return a True on success, False on error."""
     success = True
     lines = Line.readfile(input_file, name)
     checker = Checker(name, lines)
@@ -664,9 +677,7 @@ def check_file(input_file, name, subs, config, failure_handler):
     # Run all the REQUIRES lines first,
     # if any of them fail it's a SKIP
     for reqcmd in checker.requirecmds:
-        proc = runproc(
-            perform_substitution(reqcmd.args, subs)
-        )
+        proc = runproc(perform_substitution(reqcmd.args, subs))
         proc.communicate()
         if proc.returncode > 0:
             return SKIP
@@ -710,7 +721,7 @@ def parse_subs(subs):
 
 
 def get_argparse():
-    """ Return a littlecheck argument parser. """
+    """Return a littlecheck argument parser."""
     parser = argparse.ArgumentParser(
         description="littlecheck: command line tool tester."
     )
diff --git a/tests/pexpect_helper.py b/tests/pexpect_helper.py
index 85c0bab6c..5a8e4f3f4 100644
--- a/tests/pexpect_helper.py
+++ b/tests/pexpect_helper.py
@@ -43,7 +43,8 @@ SANITIZE_FOR_PRINTING_RE = re.compile(
         | \x1b>
         | \x1b\].*?\x07
     """,
-    re.VERBOSE)
+    re.VERBOSE,
+)
 
 
 def get_prompt_re(counter):
@@ -129,10 +130,12 @@ class Message(object):
         """Return a output message with the given text."""
         return Message(Message.DIR_OUTPUT, text, when)
 
+
 # Sequences for moving the cursor below the commandline. This happens before executing.
 MOVE_TO_END: str = r"(?:\r\n|\x1b\[2 q|)"
-TO_END: str  = MOVE_TO_END + r"[^\n]*"
-TO_END_SUFFIX: str  = r"[^\n]*" + MOVE_TO_END
+TO_END: str = MOVE_TO_END + r"[^\n]*"
+TO_END_SUFFIX: str = r"[^\n]*" + MOVE_TO_END
+
 
 class SpawnedProc(object):
     """A process, talking to our ptty. This wraps pexpect.spawn.
@@ -160,6 +163,7 @@ class SpawnedProc(object):
             env: a string->string dictionary, describing the environment variables.
         """
         import shlex
+
         if name not in env:
             raise ValueError("'%s' variable not found in environment" % name)
         exe_path = env.get(name)
@@ -176,7 +180,7 @@ class SpawnedProc(object):
         self.spawn.delaybeforesend = None
         self.prompt_counter = 0
         if env.get("TERM") != "dumb":
-            self.spawn.send('\x1b[?123c') # Primary Device Attribute
+            self.spawn.send("\x1b[?123c")  # Primary Device Attribute
 
     def time_since_first_message(self):
         """Return a delta in seconds since the first message, or 0 if this is the first."""
@@ -270,7 +274,11 @@ class SpawnedProc(object):
         failtype = pexpect_error_type(err)
         # If we get an EOF, we check if the process exited with a signal.
         # This shows us e.g. if it crashed
-        if failtype == 'EOF' and self.spawn.signalstatus is not None and self.spawn.signalstatus != 0:
+        if (
+            failtype == "EOF"
+            and self.spawn.signalstatus is not None
+            and self.spawn.signalstatus != 0
+        ):
             failtype = "SIGNAL " + Signals(self.spawn.signalstatus).name
 
         fmtkeys = {"failtype": failtype, "pat": escape(pat)}
@@ -300,12 +308,14 @@ class SpawnedProc(object):
         print("")
         print("{CYAN}When written to the tty, this looks like:{RESET}".format(**colors))
         print("{CYAN}<-------{RESET}".format(**colors))
-        sys.stdout.write(SANITIZE_FOR_PRINTING_RE.sub('', self.spawn.before))
+        sys.stdout.write(SANITIZE_FOR_PRINTING_RE.sub("", self.spawn.before))
         sys.stdout.flush()
-        maybe_nl=""
+        maybe_nl = ""
         if not self.spawn.before.endswith("\n"):
-            maybe_nl="\n{CYAN}(no trailing newline)".format(**colors)
-        print("{RESET}{maybe_nl}{CYAN}------->{RESET}".format(maybe_nl=maybe_nl, **colors))
+            maybe_nl = "\n{CYAN}(no trailing newline)".format(**colors)
+        print(
+            "{RESET}{maybe_nl}{CYAN}------->{RESET}".format(maybe_nl=maybe_nl, **colors)
+        )
 
         print("")
 
@@ -372,22 +382,24 @@ class SpawnedProc(object):
 
 
 def control(char: str) -> str:
-    """ Returns the char sent when control is pressed along the given key. """
+    """Returns the char sent when control is pressed along the given key."""
     assert len(char) == 1
     char = char.lower()
     if ord("a") <= ord(char) <= ord("z"):
         return chr(ord(char) - ord("a") + 1)
-    return chr({
-        "@": 0,
-        "`": 0,
-        "[": 27,
-        "{": 27,
-        "\\": 28,
-        "|": 28,
-        "]": 29,
-        "}": 29,
-        "^": 30,
-        "~": 30,
-        "_": 31,
-        "?": 127,
-    }[char])
+    return chr(
+        {
+            "@": 0,
+            "`": 0,
+            "[": 27,
+            "{": 27,
+            "\\": 28,
+            "|": 28,
+            "]": 29,
+            "}": 29,
+            "^": 30,
+            "~": 30,
+            "_": 31,
+            "?": 127,
+        }[char]
+    )
diff --git a/tests/pexpects/abbrs.py b/tests/pexpects/abbrs.py
index c3f9131ee..fdd91f232 100644
--- a/tests/pexpects/abbrs.py
+++ b/tests/pexpects/abbrs.py
@@ -168,16 +168,19 @@ sendline(r"""true; and builtin echo foo """)
 expect_prompt("bar")
 sendline(r"""abbr fruit --command={git,hg,svn} banana""")
 expect_prompt()
-sendline(r"""function git; echo git $argv; end; function hg; echo hg $argv; end; function svn; echo svn $argv; end""")
+sendline(
+    r"""function git; echo git $argv; end; function hg; echo hg $argv; end; function svn; echo svn $argv; end"""
+)
 expect_prompt()
 sendline(r"""git fruit""")
 expect_prompt("git banana")
 sendline(r"""abbr""")
-expect_prompt("abbr -a --position anywhere --command git --command hg --command svn -- fruit banana")
+expect_prompt(
+    "abbr -a --position anywhere --command git --command hg --command svn -- fruit banana"
+)
 sendline(r"""function banana; echo I am a banana; end""")
 expect_prompt()
 sendline(r"""abbr fruit --command={git,hg,svn,} banana""")
 expect_prompt()
 sendline(r"""fruit foo""")
 expect_prompt("I am a banana")
-
diff --git a/tests/pexpects/bind.py b/tests/pexpects/bind.py
index c8169c1e5..456fae6cf 100644
--- a/tests/pexpects/bind.py
+++ b/tests/pexpects/bind.py
@@ -44,7 +44,9 @@ expect_prompt("")
 # Start by testing with no delay. This should transpose the words.
 send("echo abc def")
 send("\033t\r")
-expect_prompt(TO_END + "def abc\r\n")  # emacs transpose words, default timeout: no delay
+expect_prompt(
+    TO_END + "def abc\r\n"
+)  # emacs transpose words, default timeout: no delay
 
 # Now test with a delay > 0 and < the escape timeout. This should transpose
 # the words.
@@ -76,7 +78,8 @@ expect_prompt()
 # Go through a prompt cycle to let fish catch up, it may be slow due to ASAN
 sendline("echo success: default escape timeout")
 expect_prompt(
-    TO_END + "success: default escape timeout", unmatched="prime vi mode, default timeout"
+    TO_END + "success: default escape timeout",
+    unmatched="prime vi mode, default timeout",
 )
 
 send("echo fail: default escape timeout")
@@ -284,7 +287,8 @@ send("echo abc def")
 send("\033")
 send("t\r")
 expect_prompt(
-    TO_END + "def abc\r\n", unmatched="emacs transpose words fail, 200ms timeout: no delay"
+    TO_END + "def abc\r\n",
+    unmatched="emacs transpose words fail, 200ms timeout: no delay",
 )
 
 # Verify special characters, such as \cV, are not intercepted by the kernel
@@ -364,23 +368,24 @@ expect_prompt(TO_END + "b c d")
 # Check that ctrl-z can be bound
 sendline('bind ctrl-z "echo bound ctrl-z"')
 expect_prompt()
-send("\x1A")
+send("\x1a")
 expect_str("bound ctrl-z")
 
-send('echo foobar')
-send('\x02\x02\x02') # ctrl-b, backward-char
-sendline('\x1bu') # alt+u, upcase word
+send("echo foobar")
+send("\x02\x02\x02")  # ctrl-b, backward-char
+sendline("\x1bu")  # alt+u, upcase word
 expect_prompt("fooBAR")
 
-sendline('bind ctrl-z history-prefix-search-backward')
+sendline("bind ctrl-z history-prefix-search-backward")
 expect_prompt()
 sendline("echo this continues")
 expect_prompt()
-send("\x1A")
+send("\x1a")
 sendline(" with this text")
 expect_prompt("this continues with this text")
 
-sendline("""
+sendline(
+    """
     bind ctrl-g "
         commandline --insert 'echo foo ar'
         commandline -f backward-word
@@ -389,10 +394,11 @@ sendline("""
         commandline -f backward-char
         commandline -f delete-char
     "
-""".strip())
+""".strip()
+)
 expect_prompt()
-send('\x07') # ctrl-g
-send('\r')
+send("\x07")  # ctrl-g
+send("\r")
 expect_prompt("foobar")
 
 # This should do nothing instead of crash
@@ -407,7 +413,7 @@ expect_prompt()
 # (for obvious reasons this MUST BE LAST)
 sendline("function myexit; echo exit; exit; end; bind ctrl-z myexit")
 expect_prompt()
-send("\x1A")
+send("\x1a")
 expect_str("exit")
 
 for t in range(0, 50):
diff --git a/tests/pexpects/commandline.py b/tests/pexpects/commandline.py
index 0d0130080..a3ccec121 100644
--- a/tests/pexpects/commandline.py
+++ b/tests/pexpects/commandline.py
@@ -15,19 +15,21 @@ expect_prompt()
 # Test --showing-suggestion before we dirty the history
 sendline("echo hello")
 expect_prompt()
-sendline("function debug; commandline --showing-suggestion; set -g cmd_status $status; end")
+sendline(
+    "function debug; commandline --showing-suggestion; set -g cmd_status $status; end"
+)
 expect_prompt()
-sendline("bind ctrl-p debug");
+sendline("bind ctrl-p debug")
 expect_prompt()
 send("echo hell")
-sleep(0.1) # wait for suggestion to appear under CI
+sleep(0.1)  # wait for suggestion to appear under CI
 send(control("p"))
 sendline("")
 expect_prompt("hell")
 sendline("echo cmd_status: $cmd_status")
 expect_prompt("cmd_status: 0")
 send("echo goodb")
-sleep(0.1) # wait for suggestion to appear under CI
+sleep(0.1)  # wait for suggestion to appear under CI
 send(control("p"))
 sendline("")
 expect_prompt("goodb")
diff --git a/tests/pexpects/fg.py b/tests/pexpects/fg.py
index 50af50625..2034f830d 100644
--- a/tests/pexpects/fg.py
+++ b/tests/pexpects/fg.py
@@ -19,11 +19,11 @@ expect_prompt()
 # (but also does so under /bin/sh)
 testproc = "sleep 500" if platform.system() != "NetBSD" else "cat"
 sendline(testproc)
-sendline("set -l foo 'bar'1; echo $foo") # ignored because sleep is in fg
+sendline("set -l foo 'bar'1; echo $foo")  # ignored because sleep is in fg
 sleep(1.2)
 
 # ctrl-z - send job to background
-send("\x1A")
+send("\x1a")
 sleep(1.2)
 expect_prompt()
 sendline("set -l foo 'bar'2; echo $foo")
@@ -49,7 +49,7 @@ sendline("sleep 1")
 sleep(0.1)
 
 # ctrl-z - send job to background
-send("\x1A")
+send("\x1a")
 sleep(0.2)
 expect_prompt("has stopped")
 
@@ -65,7 +65,7 @@ expect_prompt("jobs: There are no jobs")
 # Ensure we can do it again.
 sendline("sleep 5")
 sleep(0.2)
-send("\x1A")
+send("\x1a")
 sleep(0.1)
 expect_prompt("has stopped")
 sendline("fg")
@@ -78,6 +78,7 @@ expect_prompt("jobs: There are no jobs")
 
 if not os.environ.get("fish_test_helper", ""):
     import sys
+
     sys.exit(127)
 
 # Regression test for #2214: foregrounding from a key binding works!
@@ -86,14 +87,14 @@ expect_prompt()
 sendline("$fish_test_helper print_stop_cont")
 sleep(0.2)
 
-send("\x1A")  # ctrl-z
+send("\x1a")  # ctrl-z
 expect_prompt("SIGTSTP")
 sleep(0.1)
 send("\x12")  # ctrl-r, placing fth in foreground
 expect_str("SIGCONT")
 
 # Do it again.
-send("\x1A")
+send("\x1a")
 expect_str("SIGTSTP")
 sleep(0.1)
 send("\x12")
diff --git a/tests/pexpects/fkr.py b/tests/pexpects/fkr.py
index 4864d9200..15383fc47 100644
--- a/tests/pexpects/fkr.py
+++ b/tests/pexpects/fkr.py
@@ -31,7 +31,7 @@ expect_str("bind ctrl-g 'do something'\r\n")
 
 # Is a non-ASCII UTF-8 sequence prefaced by an escape char handled correctly?
 sleep(0.020)
-send("\x1B")
+send("\x1b")
 expect_str("# decoded from: \\e\r\n")
 expect_str("bind escape 'do something'\r\n")
 send("ö")
diff --git a/tests/pexpects/histfile.py b/tests/pexpects/histfile.py
index 7739064a8..be03a6879 100644
--- a/tests/pexpects/histfile.py
+++ b/tests/pexpects/histfile.py
@@ -23,6 +23,7 @@ env_histfile = "xdg_data_home/fish/env_history"
 def grephistfile(line, file):
     sendline("grep '^" + line + "' " + file)
 
+
 # Verify that if we spawn fish with no fish_history env var it uses the
 # default file.
 expect_prompt()
diff --git a/tests/pexpects/history.py b/tests/pexpects/history.py
index 6034c1ddf..492066a63 100644
--- a/tests/pexpects/history.py
+++ b/tests/pexpects/history.py
@@ -111,7 +111,9 @@ expect_re("history delete -p 'echo hello'" + TO_END_SUFFIX)
 expect_re("\\[1\\] echo hello AGAIN" + TO_END_SUFFIX)
 expect_re("\\[2\\] echo hello again" + TO_END_SUFFIX)
 expect_re("Enter nothing to cancel the delete, or\r\n")
-expect_re("Enter one or more of the entry IDs or ranges like '5..12', separated by a space.\r\n")
+expect_re(
+    "Enter one or more of the entry IDs or ranges like '5..12', separated by a space.\r\n"
+)
 expect_re("For example '7 10..15 35 788..812'.\r\n")
 expect_re("Enter 'all' to delete all the matching entries.\r\n")
 expect_re("Delete which entries\\? ")
@@ -120,14 +122,10 @@ expect_prompt('Deleting history entry 1: "echo hello AGAIN"\r\n')
 
 # Verify that the deleted history entry is gone and the other one that matched
 # the prefix search above is still there.
-sendline(
-    "echo count AGAIN (history search -e -C 'echo hello AGAIN' | count)"
-)
+sendline("echo count AGAIN (history search -e -C 'echo hello AGAIN' | count)")
 expect_prompt("count AGAIN 0\r\n")
 
-sendline(
-    "echo count again (history search -e -C 'echo hello again' | count)"
-)
+sendline("echo count again (history search -e -C 'echo hello again' | count)")
 expect_prompt("count again 1\r\n")
 
 # Verify that the $history var has the expected content.
@@ -182,7 +180,9 @@ expect_prompt()
 
 # Check history filtering
 # We store anything that starts with "echo ephemeral".
-sendline("function fish_should_add_to_history; string match -q 'echo ephemeral*' -- $argv; and return 2; return 0; end")
+sendline(
+    "function fish_should_add_to_history; string match -q 'echo ephemeral*' -- $argv; and return 2; return 0; end"
+)
 expect_prompt("")
 # Check that matching the line works
 # (fish_should_add_to_history is itself stored in history so we match "ephemeral!" to avoid it)
diff --git a/tests/pexpects/pipeline.py b/tests/pexpects/pipeline.py
index a1f74d2a1..10a99afa2 100644
--- a/tests/pexpects/pipeline.py
+++ b/tests/pexpects/pipeline.py
@@ -16,6 +16,7 @@ expect_prompt()
 
 if not os.environ.get("fish_test_helper", ""):
     import sys
+
     sys.exit(127)
 
 for i in range(5):
diff --git a/tests/pexpects/prompt_redraw_loop.py b/tests/pexpects/prompt_redraw_loop.py
index 45aad38ea..438dbd893 100644
--- a/tests/pexpects/prompt_redraw_loop.py
+++ b/tests/pexpects/prompt_redraw_loop.py
@@ -17,14 +17,22 @@ expect_prompt()
 # If a process in the prompt exits with a status that would cause a message to be printed,
 # don't trigger another prompt execution which would result in an infinite loop.
 sendline("sh -c 'kill -ABRT $$'")
-expect_prompt(re.escape("fish: Job 1, 'sh -c 'kill -ABRT $$'' terminated by signal SIGABRT (Abort)"))
+expect_prompt(
+    re.escape(
+        "fish: Job 1, 'sh -c 'kill -ABRT $$'' terminated by signal SIGABRT (Abort)"
+    )
+)
 
 # Copy current prompt so we can reuse it.
 sendline("functions --copy fish_prompt fish_prompt_orig")
 expect_prompt()
 
 sendline("function fish_prompt; sh -c 'kill -ABRT $$'; fish_prompt_orig; end")
-expect_prompt(re.escape("fish: Job 1, 'sh -c 'kill -ABRT $$'' terminated by signal SIGABRT (Abort)"))
+expect_prompt(
+    re.escape(
+        "fish: Job 1, 'sh -c 'kill -ABRT $$'' terminated by signal SIGABRT (Abort)"
+    )
+)
 
 sendline("echo still alive!")
 expect_prompt("still alive!")
diff --git a/tests/pexpects/stdin_nonblocking.py b/tests/pexpects/stdin_nonblocking.py
index 06f5dec22..6855a52fc 100644
--- a/tests/pexpects/stdin_nonblocking.py
+++ b/tests/pexpects/stdin_nonblocking.py
@@ -14,6 +14,7 @@ send, sendline, expect_prompt, expect_str, sleep = (
 
 if not os.environ.get("fish_test_helper", ""):
     import sys
+
     sys.exit(127)
 
 # Launch fish_test_helper.
@@ -24,7 +25,7 @@ sendline(exe_path + " stdin_make_nonblocking")
 expect_str("stdin was blocking")
 sleep(0.1)
 
-send("\x1A")  # ctrl-Z
+send("\x1a")  # ctrl-Z
 expect_prompt("has stopped")
 
 # We don't "restore" non-blocking state when continuing a stopped job.
diff --git a/tests/pexpects/terminal.py b/tests/pexpects/terminal.py
index 5e05abb61..7683c890c 100644
--- a/tests/pexpects/terminal.py
+++ b/tests/pexpects/terminal.py
@@ -61,6 +61,7 @@ expect_prompt("0")
 
 # TODO
 import sys
+
 sys.exit(0)
 # HACK: This fails on FreeBSD, macOS and NetBSD for some reason, maybe
 # a pexpect issue?
diff --git a/tests/pexpects/undo.py b/tests/pexpects/undo.py
index 369001f0a..934d48afe 100644
--- a/tests/pexpects/undo.py
+++ b/tests/pexpects/undo.py
@@ -26,7 +26,9 @@ expect_str("echo")
 send("Redo\r")
 expect_prompt("echo word")
 
-sendline("bind x begin-undo-group 'commandline -i \"+ \"' 'commandline -i 3' end-undo-group")
+sendline(
+    "bind x begin-undo-group 'commandline -i \"+ \"' 'commandline -i 3' end-undo-group"
+)
 expect_prompt()
 send("math 2 x\r")
 expect_prompt("5")
@@ -36,8 +38,8 @@ send("Undo1\r")
 expect_prompt("41")
 
 send("math 5 x")
-send("\x02") # c-b, moving before the 3
+send("\x02")  # c-b, moving before the 3
 send("Undo")
 send("Redo")
-send("9\r") # 5 + 93
+send("9\r")  # 5 + 93
 expect_prompt("98")
diff --git a/tests/test_driver.py b/tests/test_driver.py
index 3a5b02f35..80c856ed8 100755
--- a/tests/test_driver.py
+++ b/tests/test_driver.py
@@ -122,14 +122,14 @@ def main():
     )
     argparser.add_argument("fish", nargs=1, help="Fish to test")
     argparser.add_argument("file", nargs="*", help="Tests to run")
-    args=argparser.parse_args()
+    args = argparser.parse_args()
 
     fishdir = Path(args.fish[0]).absolute()
     if not fishdir.is_dir():
         fishdir = fishdir.parent
 
     failcount = 0
-    failed=[]
+    failed = []
     passcount = 0
     skipcount = 0
     def_subs = {"%": "%"}
@@ -247,7 +247,7 @@ def main():
     if passcount + failcount + skipcount > 1:
         print(f"{passcount} / {passcount + failcount} passed ({skipcount} skipped)")
     if failcount:
-        failstr = '\n    '.join(failed)
+        failstr = "\n    ".join(failed)
         print(f"{RED}Failed tests{RESET}: \n    {failstr}")
     if passcount == 0 and failcount == 0 and skipcount:
         return 125