Unpin flake8

environment.yml

@@ -63,7 +63,7 @@ dependencies:
   - xgboost>1.6.1  # github.com/ESMValGroup/ESMValTool/issues/2779
   - xlsxwriter
   # Python packages needed for testing
-  - flake8 <5
+  - flake8
   - pytest >=3.9,!=6.0.0rc1,!=6.0.0
   - pytest-cov
   - pytest-env

environment_osx.yml

@@ -63,10 +63,10 @@ dependencies:
   - xgboost>1.6.1  # github.com/ESMValGroup/ESMValTool/issues/2779
   - xlsxwriter
   # Python packages needed for testing
+  - flake8
   - pytest >=3.9,!=6.0.0rc1,!=6.0.0
   - pytest-cov
   - pytest-env
-  - pytest-flake8
   - pytest-html !=2.1.0
   - pytest-metadata >=1.5.1
   - pytest-xdist

setup.py

@@ -69,7 +69,7 @@
     # Test dependencies
     # Execute `pip install .[test]` once and the use `pytest` to run tests
     'test': [
-        'flake8<5',  # github.com/ESMValGroup/ESMValCore/issues/1696
+        'flake8',
         'pytest>=3.9,!=6.0.0rc1,!=6.0.0',
         'pytest-cov>=2.10.1',
         'pytest-env',