add black.sh

README.creole

@@ -211,7 +211,10 @@ django-reversion-compare$ source .virtualenv/bin/activate
 (.virtualenv) django-reversion-compare$ tox
 }}}
 
-**Note:** Just call {{{./create_env.sh}}} again to update a existing virtualenv ;)
+**Note:**
+
+* Just call {{{./create_env.sh}}} again to update a existing virtualenv ;)
+* Please run {{{./black.sh}}} to reformat the code **before** creating a pull requests
 
 == running tests
 

black.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+VIRTUALENV=.virtualenv
+
+if [[ ! -d ${VIRTUALENV} ]]; then
+    echo -e "ERROR: Virtualenv not found here: '${VIRTUALENV}'"
+    exit -1
+fi
+
+source ${VIRTUALENV}/bin/activate
+set -ex
+
+# https://github.com/ambv/black#command-line-options
+${VIRTUALENV}/bin/black --line-length=119 --safe ./reversion_compare/
+${VIRTUALENV}/bin/black --line-length=119 --safe ./reversion_compare_tests/