Give unit tests a second chance to pass

Change-Id: I495fb1ec2394130c7274368662b58212ca375854
(cherry picked from commit 976cc8f482)

.gitignore

@@ -18,6 +18,7 @@ MANIFEST
 
 .testrepository/*
 .stestr/*
+.noseids
 subunit.log
 test/probe/.noseids
 RELEASENOTES.rst

tox.ini

@@ -14,11 +14,13 @@ deps =
   -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/victoria}
   -r{toxinidir}/requirements.txt
   -r{toxinidir}/test-requirements.txt
-commands = find {envdir} ( -type f -o -type l ) -name "*.py[co]" -delete
-           find {envdir} -type d -name "__pycache__" -delete
-           nosetests {posargs:test/unit}
-whitelist_externals = find
-                      rm
+commands =
+  find {envdir} ( -type f -o -type l ) -name "*.py[co]" -delete
+  find {envdir} -type d -name "__pycache__" -delete
+  bash -ec "nosetests {posargs:test/unit} --with-id || nosetests --failed"
+allowlist_externals =
+  bash
+  find
 passenv = SWIFT_* *_proxy
 
 [testenv:py27]
@@ -96,6 +98,8 @@ commands = sphinx-build -W -b html doc/source doc/build/html
 # the API Ref to docs.openstack.org.
 basepython = python3
 deps = -r{toxinidir}/doc/requirements.txt
+allowlist_externals =
+  rm
 commands =
   rm -rf api-ref/build
   sphinx-build -W -b html -d api-ref/build/doctrees api-ref/source api-ref/build/html
@@ -153,7 +157,7 @@ deps =
 [testenv:pdf-docs]
 basepython = python3
 deps = {[testenv:docs]deps}
-whitelist_externals =
+allowlist_externals =
   make
 commands =
   sphinx-build -W -b latex doc/source doc/build/pdf