API: bump minimum version of Python to 3.7 for mpl 3.4

This is consistent with our policy and NEP29

.appveyor.yml

@@ -23,13 +23,14 @@ environment:
     # In theory we could use a single CONDA_INSTALL_LOCN because we construct
     # the envs anyway. But using one for the right python version hopefully
     # making things faster due to package caching.
-    - PYTHON_VERSION: "3.6"
-      CONDA_INSTALL_LOCN: "C:\\Miniconda36-x64"
+    - PYTHON_VERSION: "3.7"
+      CONDA_INSTALL_LOCN: "C:\\Miniconda37-x64"
       TEST_ALL: "no"
       EXTRAREQS: "-r requirements/testing/travis_extra.txt"
-    - PYTHON_VERSION: "3.7"
+    - PYTHON_VERSION: "3.8"
       CONDA_INSTALL_LOCN: "C:\\Miniconda37-x64"
       TEST_ALL: "no"
+      EXTRAREQS: "-r requirements/testing/travis_extra.txt"
 
 # We always use a 64-bit machine, but can build x86 distributions
 # with the PYTHON_ARCH variable
@@ -55,19 +56,15 @@ install:
   # For building, use a new environment
   - conda create -q -n test-environment python=%PYTHON_VERSION% tk
   - activate test-environment
+  # pull pywin32 from conda because on py38 there is something wrong with finding
+  # the dlls when insalled from pip
+  - conda install -c conda-forge pywin32
   - echo %PYTHON_VERSION% %TARGET_ARCH%
   # Install dependencies from PyPI.
   - python -mpip install --upgrade -r requirements/testing/travis_all.txt %EXTRAREQS% %PINNEDVERS%
   # Install optional dependencies from PyPI.
   # Sphinx is needed to run sphinxext tests
   - python -mpip install --upgrade sphinx
-
-  # Apply patch to `subprocess` on Python versions > 2 and < 3.6.3
-  # https://github.com/matplotlib/matplotlib/issues/9176
-  - python -c "import sys; sys.exit(not (3,) < sys.version_info < (3,6,3))" && (
-    curl -sL https://github.com/python/cpython/pull/1224.patch |
-    patch -fsup 1 -d %CONDA_PREFIX% ) || cmd /c "exit /b 0"
-
   # Show the installed packages + versions
   - conda list
 

.circleci/config.yml

@@ -110,17 +110,17 @@ commands:
 #
 
 jobs:
-  docs-python36:
+  docs-python37:
     docker:
-      - image: circleci/python:3.6
+      - image: circleci/python:3.7
     steps:
       - checkout
 
       - apt-install
       - fonts-install
       - pip-install
-      - deps-install:
-          numpy_version: "==1.13.0"
+
+      - deps-install
       - mpl-install
 
       - doc-build
@@ -130,17 +130,18 @@ jobs:
       - store_artifacts:
           path: doc/build/html
 
-  docs-python37:
+  docs-python38-min:
     docker:
-      - image: circleci/python:3.7
+      - image: circleci/python:3.8-min
     steps:
       - checkout
 
       - apt-install
       - fonts-install
       - pip-install
 
-      - deps-install
+      - deps-install:
+          numpy_version: "==1.16.0"
       - mpl-install
 
       - doc-build
@@ -185,6 +186,6 @@ workflows:
   version: 2
   build:
     jobs:
-      - docs-python36
       - docs-python37
       - docs-python38
+      - docs-python38-min

.travis.yml

@@ -73,9 +73,9 @@ env:
 
 matrix:
   include:
-    - python: 3.6
+    - python: 3.7
       env:
-        - PINNEDVERS='-c requirements/testing/travis36minver.txt'
+        - PINNEDVERS='-c requirements/testing/minver.txt'
         - DELETE_FONT_CACHE=1
     - python: 3.7
       env:

INSTALL.rst

@@ -115,7 +115,7 @@ Dependencies
 
 Matplotlib requires the following dependencies:
 
-* `Python <https://www.python.org/downloads/>`_ (>= 3.6)
+* `Python <https://www.python.org/downloads/>`_ (>= 3.7)
 * `NumPy <https://numpy.org>`_ (>= 1.16)
 * `setuptools <https://setuptools.readthedocs.io/en/latest/>`_
 * `cycler <https://matplotlib.org/cycler/>`_ (>= 0.10.0)

azure-pipelines.yml

@@ -5,27 +5,18 @@
 
 strategy:
   matrix:
-    Linux_py36:
-      vmImage: 'ubuntu-16.04'
-      python.version: '3.6'
     Linux_py37:
       vmImage: 'ubuntu-16.04'
       python.version: '3.7'
     Linux_py38:
       vmImage: 'ubuntu-16.04'
       python.version: '3.8'
-    macOS_py36:
-      vmImage: 'macOS-10.14'
-      python.version: '3.6'
     macOS_py37:
       vmImage: 'macOS-10.15'
       python.version: '3.7'
     macOS_py38:
       vmImage: 'macOS-latest'
       python.version: '3.8'
-    Windows_py36:
-      vmImage: 'vs2017-win2016'
-      python.version: '3.6'
     Windows_py37:
       vmImage: 'vs2017-win2016'
       python.version: '3.7'

doc/devel/coding_guide.rst

@@ -254,7 +254,7 @@ The current active branches are
 
 *master*
   The current development version. Future minor releases (*v3.N.0*) will be
-  branched from this. Supports Python 3.6+.
+  branched from this. Supports Python 3.7+.
 
 *v3.N.x*
   Maintenance branch for Matplotlib 3.N. Future patch releases will be

doc/devel/testing.rst

@@ -243,7 +243,7 @@ You can also run tox on a subset of environments:
 
 .. code-block:: bash
 
-    $ tox -e py36,py37
+    $ tox -e py37,py38
 
 Tox processes everything serially so it can take a long time to test
 several environments. To speed it up, you might try using a new,

doc/faq/installing_faq.rst

@@ -105,7 +105,7 @@ the form of wheels.
 pip is installed by default with python.org and Homebrew Python, but needs to
 be manually installed on Macports with ::
 
-   sudo port install py36-pip
+   sudo port install py38-pip
 
 Once pip is installed, you can install Matplotlib and all its dependencies with
 from the Terminal.app command line::

setup.py

@@ -8,7 +8,7 @@
 # and/or pip.
 import sys
 
-min_version = (3, 6)
+min_version = (3, 7)
 
 if sys.version_info < min_version:
     error = """

tox.ini

@@ -4,7 +4,7 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = py36, py37, py38
+envlist = py37, py38
 
 [testenv]
 changedir = /tmp