MyPy CI Configuration

.gitignore

@@ -61,6 +61,7 @@ dist
 .coverage
 coverage.xml
 coverage_html_report
+.mypy_cache
 *.pytest_cache
 # hypothesis test database
 .hypothesis/

azure-pipelines.yml

@@ -88,6 +88,13 @@ jobs:
     displayName: 'Docstring validation'
     condition: true
 
+  - script: |
+      export PATH=$HOME/miniconda3/bin:$PATH
+      source activate pandas-dev
+      ci/code_checks.sh typing
+    displayName: 'Typing validation'
+    condition: true
+
   - script: |
       export PATH=$HOME/miniconda3/bin:$PATH
       source activate pandas-dev

ci/code_checks.sh

@@ -16,9 +16,10 @@
 #   $ ./ci/code_checks.sh doctests      # run doctests
 #   $ ./ci/code_checks.sh docstrings    # validate docstring errors
 #   $ ./ci/code_checks.sh dependencies  # check that dependencies are consistent
+#   $ ./ci/code_checks.sh typing	# run static type analysis
 
-[[ -z "$1" || "$1" == "lint" || "$1" == "patterns" || "$1" == "code" || "$1" == "doctests" || "$1" == "docstrings" || "$1" == "dependencies" ]] || \
-    { echo "Unknown command $1. Usage: $0 [lint|patterns|code|doctests|docstrings|dependencies]"; exit 9999; }
+[[ -z "$1" || "$1" == "lint" || "$1" == "patterns" || "$1" == "code" || "$1" == "doctests" || "$1" == "docstrings" || "$1" == "dependencies" || "$1" == "typing" ]] || \
+    { echo "Unknown command $1. Usage: $0 [lint|patterns|code|doctests|docstrings|dependencies|typing]"; exit 9999; }
 
 BASE_DIR="$(dirname $0)/.."
 RET=0
@@ -256,4 +257,16 @@ if [[ -z "$CHECK" || "$CHECK" == "dependencies" ]]; then
 
 fi
 
+### TYPING ###
+if [[ -z "$CHECK" || "$CHECK" == "typing" ]]; then
+
+    echo "mypy --version"
+    mypy --version
+
+    MSG='Performing static analysis on items in mypy_whitelist.txt' ; echo $MSG
+    mypy @mypy_whitelist.txt
+    RET=$(($RET + $?)) ; echo $MSG "DONE"
+fi
+
+
 exit $RET

environment.yml

@@ -19,6 +19,7 @@ dependencies:
   - hypothesis>=3.82
   - isort
   - moto
+  - mypy
   - pycodestyle
   - pytest>=4.0.2
   - pytest-mock

mypy.ini

@@ -0,0 +1,6 @@
+[mypy]
+ignore_missing_imports=True
+follow_imports=silent
+
+[mypy-pandas.conftest,pandas.tests.*]
+ignore_errors=True

mypy_whitelist.txt

@@ -0,0 +1,4 @@
+pandas/core/arrays/base.py
+pandas/core/arrays/datetimes.py
+pandas/core/common.py
+pandas/core/dtypes/base.py

pandas/core/internals/blocks.py

@@ -1827,10 +1827,9 @@ def interpolate(self, method='pad', axis=0, inplace=False, limit=None,
             placement=self.mgr_locs)
 
     def shift(self,
-              periods,                  # type: int
-              axis=0,                   # type: libinternals.BlockPlacement
-              fill_value=None):         # type: Any
-        # type: (...) -> List[ExtensionBlock]
+              periods: int,
+              axis: libinternals.BlockPlacement = 0,
+              fill_value: Any = None) -> List['ExtensionBlock']:
         """
         Shift the block by `periods`.
 

requirements-dev.txt

@@ -10,6 +10,7 @@ gitpython
 hypothesis>=3.82
 isort
 moto
+mypy
 pycodestyle
 pytest>=4.0.2
 pytest-mock