Removing Python 2 configurations for CI runs

.circleci/config.yml

@@ -1,11 +1,11 @@
 version: 2
 
 jobs:
-  osx-python2:
+  osx-python3.6:
     macos:
-      xcode: "10.0.0"
+      xcode: "9.4.1"
     environment:
-      PYTHON: python2
+      PYTHON: python3
     steps:
       - checkout
 
@@ -16,7 +16,7 @@ jobs:
           name: Test.
           command: venv/bin/python ./bin/run_tests.py
 
-  osx-python3:
+  osx-python3.7:
     macos:
       xcode: "10.0.0"
     environment:
@@ -31,23 +31,7 @@ jobs:
           name: Test.
           command: venv/bin/python ./bin/run_tests.py
 
-  linux-python2:
-    docker:
-      - image: circleci/python:2.7
-    environment:
-      PYTHON: python2
-    steps:
-      - checkout
-      - setup_remote_docker
-
-      - run:
-          name: Prepare the environment.
-          command: bash .circleci/prepare.sh
-      - run:
-          name: Test.
-          command: venv/bin/python ./bin/run_tests.py
-
-  linux-python3:
+  linux-python3.6:
     docker:
       - image: circleci/python:3.6
     environment:
@@ -67,7 +51,6 @@ workflows:
   version: 2
   all-tests:
     jobs:
-      - osx-python2
-      - osx-python3
-      - linux-python2
-      - linux-python3
+      - osx-python3.6
+      - osx-python3.7
+      - linux-python3.6

.travis.yml

@@ -2,13 +2,6 @@ language: generic
 
 matrix:
   include:
-    # Linux Python 2
-    - sudo: required
-      language: python
-      python: 2.7
-      services: docker
-      env: PYTHON=python
-
     # Linux Python 3
     - sudo: required
       language: python

CI.md

@@ -0,0 +1,9 @@
+This is a summary of the Python versions and platforms covered by the different CI platforms:
+
+|          | 3.5        | 3.6                | 3.7                   | 3.8              |
+|----------|------------|--------------------|-----------------------|------------------|
+| Linux    | Travis CI  | CircleCI           | AppVeyor              | Azure Pipelines  |
+| macOS    |            | CircleCI           | Travis CI* / CircleCI | Azure Pipelines  |
+| Windows  | TravisCI   | AppVeyor (32-bit)  | AppVeyor (64-bit)     | Azure Pipelines  |
+
+> * Not really pinned, but dependent on the (default) version of image used.

appveyor.yml

@@ -1,11 +1,15 @@
-image:
-  - Ubuntu
-  - Visual Studio 2015
+environment:
+  matrix:
+    - image: Ubuntu
+    - image: Visual Studio 2015
+      PYTHON_VERSION: 36
+    - image: Visual Studio 2015
+      PYTHON_VERSION: 37-x64
 
 build_script:
-  - cmd: "C:\\Python27\\python.exe -m pip install -r requirements-dev.txt"
+  - cmd: "C:\\Python%PYTHON_VERSION%\\python.exe -m pip install -r requirements-dev.txt"
   - sh: "${HOME}/.localpython3.7.4/bin/python3 -m pip install -r requirements-dev.txt"
   # the '-u' flag is required so the output is in the correct order.
   # See https://github.com/joerick/cibuildwheel/pull/24 for more info.
-  - cmd: "C:\\Python27\\python.exe -u ./bin/run_tests.py"
+  - cmd: "C:\\Python%PYTHON_VERSION%\\python.exe -u ./bin/run_tests.py"
   - sh: "${HOME}/.localpython3.7.4/bin/python3 ./bin/run_tests.py"