Mention autopep8 in Hacking.rst

The scripts in the tools now is able to distinguish,
the autopep8 error codes better.

Change-Id: I9ea19009118ed418e3666fad45d2e0eb676204c8

HACKING.rst

@@ -28,6 +28,8 @@ Tempest Specific Commandments
 - [T117] Check negative tests have ``@decorators.attr(type=['negative'])``
   applied.
 
+It is recommended to use ``tox -eautopep8`` before submitting a patch.
+
 Test Data/Configuration
 -----------------------
 - Assume nothing about existing test data

tools/format.sh

@@ -1,5 +1,29 @@
 #!/bin/bash
+
 cd $(dirname "$(readlink -f "$0")")
 
-autopep8 --exit-code --max-line-length=79 --experimental --in-place -r ../tempest ../setup.py && echo Formatting was not needed. >&2
+AUTOPEP8=`which autopep8 2>/dev/null`
 
+if [[ -z "$AUTOPEP8" ]]; then
+    AUTOPEP8=`which autopep8-3`
+fi
+
+if [[ -z "$AUTOPEP8" ]]; then
+    echo "Unable to locate autopep8" >&2
+    exit 2
+fi
+
+# isort is not compatible with the default flake8 (H306), maybe flake8-isort
+# isort -rc -sl -fss ../tempest ../setup.py
+$AUTOPEP8 --exit-code --max-line-length=79 --experimental --in-place -r ../tempest ../setup.py
+ERROR=$?
+
+if [[ $ERROR -eq 0 ]]; then
+    echo "Formatting was not needed." >&2
+    exit 0
+elif [[ $ERROR -eq 1 ]]; then
+    echo "Formatting failed.." >&2
+    exit 1
+else
+    echo "done" >&2
+fi

tox.ini

@@ -198,7 +198,7 @@ whitelist_externals = rm
 
 [testenv:pep8]
 deps =
-    -r test-requirements.txt
+    -r{toxinidir}/test-requirements.txt
     autopep8
 basepython = python3
 commands =
@@ -210,7 +210,7 @@ commands =
 deps = autopep8
 basepython = python3
 commands =
-    autopep8 --max-line-length=79  --experimental --in-place -r tempest setup.py
+    {toxinidir}/tools/format.sh
 
 [testenv:uuidgen]
 commands =