Merge pull request matplotlib#25186 from meeseeksmachine/auto-backport-of-pr-24893-on-v3.7.x

Author: ksunden

.flake8

@@ -1,5 +1,5 @@
 [flake8]
-max-line-length = 79
+max-line-length = 88
 select =
     # flake8 default
     C90, E, F, W,

doc/api/next_api_changes/development/24893-KS.rst

@@ -0,0 +1,8 @@
+Maximum line length increased to 88 characters
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The maximum line length for new contributions has been extended from 79 characters to
+88 characters.
+This change provides an extra 9 characters to allow code which is a single idea to fit
+on fewer lines (often a single line).
+The chosen length is the same as `black <https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#line-length>`_.

doc/devel/MEP/MEP08.rst

@@ -9,7 +9,10 @@
 Status
 ======
 
-**Completed**
+**Superseded**
+
+Current guidelines for style, including usage of pep8 are maintained
+in `our pull request guidelines <https://matplotlib.org/devdocs/devel/coding_guide.html>`_.
 
 We are currently enforcing a sub-set of pep8 on new code contributions.
 

doc/devel/coding_guide.rst

@@ -30,7 +30,8 @@ rules before submitting a pull request:
   for more details.
 
 * Formatting should follow the recommendations of PEP8_, as enforced by
-  flake8_.  You can check flake8 compliance from the command line with ::
+  flake8_. Matplotlib modifies PEP8 to extend the maximum line length to 88
+  characters. You can check flake8 compliance from the command line with ::
 
     python -m pip install flake8
     flake8 /path/to/module.py
@@ -156,6 +157,11 @@ Content topics:
 * Does the PR conform with the :ref:`coding_guidelines`?
 * Is the :ref:`documentation <pr-documentation>` (docstrings, examples,
   what's new, API changes) updated?
+* Is the change purely stylistic? Generally, such changes are discouraged when
+  not part of other non-stylistic work because it obscures the git history of
+  functional changes to the code. Reflowing a method or docstring as part of a
+  larger refactor/rewrite is acceptable.
+
 
 Organizational topics: