CONTRIBUTING.rst: Added section in PEP-8 coding style about line lengths.

We have a long line limit in order to handle the exceptions without making
code unreadable as a result, this long line length limit is not an invitation
to fill up the limit as much as possible.

1 files changed, 15 insertions, 0 deletions

diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
index 6493979f0..83a8a4a05 100644
--- a/CONTRIBUTING.rst
+++ b/CONTRIBUTING.rst
@@ -192,6 +192,21 @@ code readability by being overly restrictive on line length for instance.
 The pep8 linter will run automatically when :ref:`running the test suite <contributing_testing>`.
 
 
+Line lengths
+''''''''''''
+Regarding laxness on the line length in our linter settings, it should be clarified
+that the line length limit is a hard limit which causes the linter to bail out
+and reject commits which break the high limit - not an invitation to write exceedingly
+long lines of code, comments, or API documenting docstrings.
+
+Code, comments and docstrings should strive to remain written for approximately 80
+or 90 character lines, where exceptions can be made when code would be less readable
+when exceeding 80 or 90 characters (often this happens in conditional statements
+when raising an exception, for example). Or, when comments contain a long link that
+causes the given line to to exceed 80 or 90 characters, we don't want this to cause
+the linter to refuse the commit.
+
+
 .. _contributing_documenting_symbols:
 
 Documenting symbols