tox: run tests against python 3 (#36515)

Jenkinsfile

@@ -4,9 +4,9 @@ pipeline {
     agent any
     options { disableConcurrentBuilds() }
     stages {
-        stage('Unit Tests') {
+        stage('Unit Tests (Python 2)') {
             steps {
-                sh 'tox -r'
+                sh 'tox -r -e py2-pylint-coverage'
             }
             post {
                 always {
@@ -20,6 +20,11 @@ pipeline {
                 }
             }
         }
+        stage('Unit Tests (Python 3)') {
+            steps {
+                sh 'tox -r -e py3'
+            }
+        }
         stage('Packaging') {
             steps {
                 script {

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 toxworkdir = {env:TMPDIR:/tmp}/tox-{env:USER}/wcs/{env:BRANCH_NAME:}
-envlist = py2-pylint-coverage
+envlist = py2-pylint-coverage,py3
 
 [testenv]
 sitepackages = true
@@ -16,7 +16,8 @@ setenv =
 passenv =
     USER
 deps =
-    pytest
+    py2: pytest
+    py3: pytest>=3.6,<5
     pytest-mock
     pytest-cov
     pytest-django
@@ -29,6 +30,7 @@ deps =
     django-ratelimit<3
     pyproj
     pylint<1.8
+    py3: Quixote>=3.0
 commands =
-    py.test {env:COVERAGE:} {posargs:tests/}
+    py.test -v {env:COVERAGE:} {posargs:tests/}
     pylint: ./pylint.sh wcs/