Adds pre-commit config to run various lintersci_improvements

This ads black, isort, pyupgrade, and flake8 to pre-commit-config.yaml
There are also some small changes to travis.yml and tasks.py to reduce
some repeated configurations that should be consolidated into
setup.cfg. Most other changes are automated by the linter scripts.

1 files changed, 14 insertions, 4 deletions

diff --git a/cmd2/ansi.py b/cmd2/ansi.py
index f172b87f..9d7ce0ee 100644
--- a/cmd2/ansi.py
+++ b/cmd2/ansi.py
@@ -59,6 +59,7 @@ class ColorBase(Enum):
 
         value: anything that when cast to a string returns an ANSI sequence
     """
+
     def __str__(self) -> str:
         """
         Return ANSI color sequence instead of enum name
@@ -92,6 +93,7 @@ class ColorBase(Enum):
 # noinspection PyPep8Naming
 class fg(ColorBase):
     """Enum class for foreground colors"""
+
     black = Fore.BLACK
     red = Fore.RED
     green = Fore.GREEN
@@ -115,6 +117,7 @@ class fg(ColorBase):
 # noinspection PyPep8Naming
 class bg(ColorBase):
     """Enum class for background colors"""
+
     black = Back.BLACK
     red = Back.RED
     green = Back.GREEN
@@ -184,8 +187,7 @@ def style_aware_write(fileobj: IO, msg: str) -> None:
     :param fileobj: the file object being written to
     :param msg: the string being written
     """
-    if allow_style.lower() == STYLE_NEVER.lower() or \
-            (allow_style.lower() == STYLE_TERMINAL.lower() and not fileobj.isatty()):
+    if allow_style.lower() == STYLE_NEVER.lower() or (allow_style.lower() == STYLE_TERMINAL.lower() and not fileobj.isatty()):
         msg = strip_style(msg)
     fileobj.write(msg)
 
@@ -227,8 +229,15 @@ def bg_lookup(bg_name: Union[str, bg]) -> str:
 
 
 # noinspection PyShadowingNames
-def style(text: Any, *, fg: Union[str, fg] = '', bg: Union[str, bg] = '', bold: bool = False,
-          dim: bool = False, underline: bool = False) -> str:
+def style(
+    text: Any,
+    *,
+    fg: Union[str, fg] = '',
+    bg: Union[str, bg] = '',
+    bold: bool = False,
+    dim: bool = False,
+    underline: bool = False
+) -> str:
     """
     Apply ANSI colors and/or styles to a string and return it.
     The styling is self contained which means that at the end of the string reset code(s) are issued
@@ -302,6 +311,7 @@ def async_alert_str(*, terminal_columns: int, prompt: str, line: str, cursor_off
     :return: the correct string so that the alert message appears to the user to be printed above the current line.
     """
     from colorama import Cursor
+
     # Split the prompt lines since it can contain newline characters.
     prompt_lines = prompt.splitlines()