Turn on pip's new feature - use-feature=2020-resolver (slackapi#42)

seratch · web-flow · commit 6e4a6fc72c4c · 2020-08-25T10:56:59.000+09:00
diff --git a/.github/maintainers_guide.md b/.github/maintainers_guide.md
@@ -39,6 +39,23 @@ $ python -m venv env_3.8.5
 $ source env_3.8.5/bin/activate
 ```
 
+### Additional settings for pip
+
+pip 20.2 introduced a new flag to test the upcoming change: https://discuss.python.org/t/announcement-pip-20-2-release/4863/2
+Turn on the feature on your local machine for testing it. Just running the following command helps you turn it on.
+
+```bash
+pip config set global.use-feature 2020-resolver
+```
+
+The following file should be generated.
+
+```yaml
+# ~/.config/pip/pip.conf
+[global]
+use-feature = 2020-resolver
+```
+
 ## Tasks
 
 ### Testing
diff --git a/.travis.yml b/.travis.yml
@@ -7,6 +7,8 @@ python:
 install:
   - python setup.py install
   - pip install -U pip
+  # https://discuss.python.org/t/announcement-pip-20-2-release/4863
+  - pip config set global.use-feature 2020-resolver
   - pip install "pytest>=5,<6"
   - pip install "pytype"
 script:
