Add pre-commit hook config (#2963)

* Add pre-commit config file.

* Tweak config after running on all files.

* Add exclude to flake8 config.

* Add pre-commit to dev extras in pyproject.toml

* Add pre-commit install to README.

* Address whitespace and no newlines across repo.

* Address flake8 finding in test_utils.py

Author: stefmolin

.pre-commit-config.yaml

@@ -0,0 +1,20 @@
+repos:
+-   repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.3.0
+    hooks:
+    -   id: check-yaml
+    -   id: end-of-file-fixer
+    -   id: trailing-whitespace
+        exclude: \.svg$
+-   repo: https://github.com/pycqa/flake8
+    rev: 5.0.4
+    hooks:
+    -   id: flake8
+        exclude: seaborn/(cm\.py|external/)
+        types: [file, python]
+-   repo: https://github.com/pre-commit/mirrors-mypy
+    rev: v0.971
+    hooks:
+     -  id: mypy
+        args: [--follow-imports=skip]
+        files: seaborn/_(core|marks|stats)/

README.md

@@ -64,12 +64,11 @@ To test the code, run `make test` in the source directory. This will exercise bo
 
 The doctests require a network connection (unless all example datasets are cached), but the unit tests can be run offline with `make unittests`.
 
-Code style is enforced with `flake8` using the settings in the [`setup.cfg`](./setup.cfg) file. Run `make lint` to check.
- 
+Code style is enforced with `flake8` using the settings in the [`setup.cfg`](./setup.cfg) file. Run `make lint` to check. Alternately, you can use `pre-commit` to automatically run lint checks on any files you are committing – just run `pre-commit install` to set it up, and then commit as usual going forward.
+
 Development
 -----------
 
 Seaborn development takes place on Github: https://github.com/mwaskom/seaborn
 
 Please submit bugs that you encounter to the [issue tracker](https://github.com/mwaskom/seaborn/issues) with a reproducible example demonstrating the problem. Questions about usage are more at home on StackOverflow, where there is a [seaborn tag](https://stackoverflow.com/questions/tagged/seaborn).
-

ci/deps_pinned.txt

@@ -5,4 +5,4 @@ scipy~=1.3.0
 statsmodels~=0.10.0
 # Pillow added in install_requires for later matplotlibs
 pillow>=6.2.0
-typing_extensions
+typing_extensions

ci/getmsfonts.sh

@@ -1,3 +1,2 @@
 echo ttf-mscorefonts-installer msttcorefonts/accepted-mscorefonts-eula select true | debconf-set-selections
 apt-get install msttcorefonts -qq
-

doc/README.md

@@ -5,7 +5,7 @@ Building the docs requires additional dependencies; they can be installed with `
 
 The build process involves conversion of Jupyter notebooks to `rst` files. To facilitate this, you may need to set `NB_KERNEL` environment variable to the name of a kernel on your machine (e.g. `export NB_KERNEL="python3"`). To get a list of available Python kernels, run `jupyter kernelspec list`.
 
-After you're set up, run `make notebooks html` from the `doc` directory to convert all notebooks, generate all gallery examples, and build the documentation itself. The site will live in `_build/html`. 
+After you're set up, run `make notebooks html` from the `doc` directory to convert all notebooks, generate all gallery examples, and build the documentation itself. The site will live in `_build/html`.
 
 Run `make clean` to delete the built site and all intermediate files. Run `make -C docstrings clean` or `make -C tutorial clean` to remove intermediate files for the API or tutorial components.
 

doc/_static/copybutton.js

@@ -2,11 +2,11 @@
 $(document).ready(function() {
     /* Add a [>>>] button on the top-right corner of code samples to hide
      * the >>> and ... prompts and the output and thus make the code
-     * copyable. 
+     * copyable.
      * Note: This JS snippet was taken from the official python.org
      * documentation site.*/
     var div = $('.highlight-python .highlight,' +
-                '.highlight-python3 .highlight,' + 
+                '.highlight-python3 .highlight,' +
                 '.highlight-pycon .highlight')
     var pre = div.find('pre');
 

doc/_templates/autosummary/base.rst

@@ -3,4 +3,3 @@
 .. currentmodule:: {{ module }}
 
 .. auto{{ objtype }}:: {{ objname }}
-

doc/_templates/autosummary/object.rst

@@ -3,4 +3,3 @@
 .. currentmodule:: {{ module }}
 
 .. autoclass:: {{ objname }}
-

doc/citing.rst

@@ -45,13 +45,13 @@ Tall logo
 ~~~~~~~~~
 
 .. image:: _static/logo-tall-lightbg.svg
-   :width: 150px 
+   :width: 150px
 
 Logo mark
 ~~~~~~~~~
 
 .. image:: _static/logo-mark-lightbg.svg
-   :width: 150px 
+   :width: 150px
 
 Credit to `Matthias Bussonnier <https://github.com/Carreau>`_ for the initial design
-and implementation of the logo.
+and implementation of the logo.

doc/faq.rst

@@ -68,7 +68,7 @@ The default "inline" backend (defined by `IPython <https://github.com/ipython/ma
 You can increase the DPI by resetting the rc parameters through the matplotlib API, using
 
 ::
-    
+
     plt.rcParams.update({"figure.dpi": 96})
 
 Or do it as you activate the seaborn theme::
@@ -80,9 +80,9 @@ If you have a high pixel-density monitor, you can make your plots sharper using
     %config InlineBackend.figure_format = "retina"
 
 This won't change the apparent size of your plots in a Jupyter interface, but they might appear very large in other contexts (i.e. on GitHub). And they will take up 4x the disk space. Alternatively, you can make SVG plots::
-    
+
     %config InlineBackend.figure_format = "svg"
-    
+
 This will configure matplotlib to emit `vector graphics <https://en.wikipedia.org/wiki/Vector_graphics>`_ with "infinite resolution". The downside is that file size will now scale with the number and complexity of the artists in your plot, and in some cases (e.g., a large scatterplot matrix) the load will impact browser responsiveness.
 
 Tricky concepts