Migrate from testr to stestr

* Replace .testr.conf by .stestr.conf for migration and update
  .gitignore, test-requirements.txt and lower-constraints.txt
  files accordingly
* Use py3 as the default runtime for tox and 3.18.0 as the
  minversion for tox
* Add a new job, openstack-cover-jobs, to run the coverage in Zuul
* Create cover environment in tox and make relevant changes
  in .gitignore

Signed-off-by: HeroicHitesh <email.hiteshkumar@gmail.com>
Change-Id: I3de659cdda2f490590dbfb38c81b95becac5da7c

.gitignore

@@ -1,11 +1,24 @@
 *.pyc
-*.swp
-*~
-.tox
-.testrepository
+
+# Packages
+*.egg*
+*.egg-info
 build
+
+# Unit test / coverage reports
+cover/
+.coverage*
+!.coveragerc
+.tox
+.stestr/
+
+# pbr generates these
 AUTHORS
 ChangeLog
 
+# Editors
+*.swp
+*~
+
 # Files created by releasenotes build
 releasenotes/build

.stestr.conf

@@ -0,0 +1,3 @@
+[DEFAULT]
+test_path=./tests/
+top_dir=./

.testr.conf

@@ -1,4 +0,0 @@
-[DEFAULT]
-test_command=${PYTHON:-python} -m subunit.run discover -t ./ . $LISTOPT $IDOPTION
-test_id_option=--load-list $IDFILE
-test_list_option=--list

.zuul.yaml

@@ -5,3 +5,4 @@
       - publish-openstack-docs-pti
       - release-notes-jobs-python3
       - openstack-lower-constraints-jobs
+      - openstack-cover-jobs

lower-constraints.txt

@@ -66,7 +66,7 @@ salt==3001.1
 simplejson==3.5.1
 six==1.10.0
 stevedore==1.20.0
-testrepository==0.0.18
+stestr==2.0.0
 testscenarios==0.4
 testtools==2.2.0
 tornado==4.4.3

test-requirements.txt

@@ -8,7 +8,7 @@ hacking>=3.0.1,<3.1.0 # Apache-2.0
 requests>=2.14.2 # Apache-2.0
 requests-mock>=1.1.0 # Apache-2.0
 salt>=3001.1  # Apache-2.0
-testrepository>=0.0.18 # Apache-2.0/BSD
+stestr>=2.0.0 # Apache-2.0
 testscenarios>=0.4 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT
 os-apply-config>=5.0.0 # Apache-2.0

tox.ini

@@ -1,18 +1,17 @@
 [tox]
-envlist = py38,pep8
+envlist = py3,pep8
 ignore_basepython_conflict = true
-minversion = 3.1.0
+minversion = 3.18.0
 skipsdist = True
 
 [testenv]
 basepython = python3
-whitelist_externals = bash
+allowlist_externals = bash
 setenv = VIRTUAL_ENV={envdir}
 deps =  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
        -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
-commands = bash -c 'if [ ! -d ./.testrepository ] ; then testr init ; fi'
-           testr run {posargs}
+commands= stestr run --slowest {posargs}
 
 [testenv:pep8]
 commands = flake8
@@ -31,6 +30,20 @@ show-source = True
 builtins = _
 exclude=.venv,.git,.tox,*lib/python*,private,.eggs
 
+[testenv:cover]
+basepython = python3
+allowlist_externals = find
+setenv =
+  PYTHON=coverage run --source . --parallel-mode
+commands =
+  coverage erase
+  find . -type f -name "*.pyc" -delete
+  stestr run {posargs}
+  coverage combine
+  coverage html -d cover
+  coverage xml -o cover/coverage.xml
+  coverage report
+
 [testenv:releasenotes]
 deps =
     -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}