Merge pull request #788 from PCMDI/787_ljw_pre-commit-hook

I am merging this PR and will open another PR for make existing files to be compliant to the pre-commit-hook

.pre-commit-config.yaml

@@ -0,0 +1,27 @@
+exclude: "docs|node_modules|migrations|.git|.tox"
+default_stages: [commit]
+fail_fast: true
+
+repos:
+    - repo: https://github.com/pre-commit/pre-commit-hooks
+      rev: v3.4.0
+      hooks:
+          - id: trailing-whitespace
+          - id: end-of-file-fixer
+          - id: check-yaml
+
+    # Need to use flake8 GitHub mirror due to CentOS git issue with GitLab
+    # https://github.com/pre-commit/pre-commit/issues/1206
+    - repo: https://github.com/pycqa/flake8
+      rev: 3.9.2
+      hooks:
+          - id: flake8
+            args: ["--config=setup.cfg"]
+            additional_dependencies: [flake8-isort]
+            exclude: ^sample_setups/jsons/
+
+    - repo: https://github.com/pre-commit/mirrors-mypy
+      rev: v0.910
+      hooks:
+          - id: mypy
+            args: ["--config=setup.cfg"]

setup.cfg

@@ -1,4 +1,42 @@
+[flake8]
+# https://pep8.readthedocs.io/en/latest/intro.html#error-codes
+ignore =
+    # whitespace before ‘:’
+    E203
+    # line too long (82 > 79 characters)
+    E501
+    # line break before operator
+    W503
+# Max width of Github code review is 119 characters
+max-line-length = 119
+max-complexity = 10
+exclude =
+    .tox
+    .git
+    */migrations/*
+    */static/CACHE/*
+    docs
+    node_modules
+    .idea
+    .mypy_cache
+    .pytest_cache
+    *__init__.py
+    venv
+    *json
+
+[mypy]
+python_version = 3.8
+check_untyped_defs = True
+ignore_missing_imports = True
+warn_unused_ignores = True
+warn_redundant_casts = True
+warn_unused_configs = True
+
+[aliases]
+# Define setup.py command aliases here
+test = pytest
+
 [tool:pytest]
-junit_family=xunit2
+junit_family = xunit2
 addopts = --cov=pcmdi_metrics --cov-report term --cov-report html:tests_coverage_reports/htmlcov --cov-report xml:tests_coverage_reports/coverage.xml -s --ignore tests/deprecated
-python_files = tests.py test_*.py
+python_files = tests.py test_*.py