Switch from testrepository to stestr

This commit replaces the call to testr with stestr, and updates the
output files accordingly. This is necessary because tempest has moved
away from testrepository [1], which is resulting in empty files being
created.

Lastly, we update the functional tests to ensure the subunit results
files exist and are not empty.

[1] https://review.openstack.org/#/c/504345/

Change-Id: I2496fccff1f51c586e999538232a4bcf0addbee5

tasks/tempest_run.yml

@@ -29,9 +29,14 @@
 
   always:
   - name: Generate raw subunit results
+    # Despite not using testrepository, we leave the output filename as
+    # testrepository.subunit as the OpenStack Health dashboard relies on
+    # subunit files with this particular name.
+    # NOTE(mattt): At present we're not placing this file in a valid location
+    # to be used by the OpenStack Health dashboard.
     shell: |
       . {{ tempest_venv_bin }}/activate
-      testr last --subunit > {{ tempest_log_dir }}/testrepository.subunit
+      stestr last --subunit > {{ tempest_log_dir }}/testrepository.subunit
     args:
       chdir: "{{ tempest_venv_bin | dirname }}/workspace"
       executable: /bin/bash
@@ -57,7 +62,7 @@
   - name: Generate html subunit results
     shell: |
       . {{ tempest_venv_bin }}/activate
-      subunit2html {{ tempest_log_dir }}/testrepository.subunit {{ tempest_log_dir }}/testr_results.html
+      subunit2html {{ tempest_log_dir }}/testrepository.subunit {{ tempest_log_dir }}/stestr_results.html
     args:
       chdir: "{{ tempest_venv_bin | dirname }}/workspace"
       executable: /bin/bash

tests/test-tempest-functional.yml

@@ -31,19 +31,20 @@
       tags:
         - skip_ansible_lint
 
-    - name: List the contents of the tempest_result_path folder
+    - name: Stat the tempest subunit result files
-      find:
+      stat:
-        paths: "{{ tempest_log_dir }}"
+        path: "{{ tempest_log_dir }}/{{ item }}"
+      with_items:
+        - "stestr_results.html"
+        - "tempest_results.xml"
+        - "testrepository.subunit"
       register: _results_list
 
     - name: Check whether the expected subunit result files are present
       assert:
-        that: "item in _results_list.files | map(attribute='path') | map('basename') | list"
+        that: item.stat.exists and item.stat.size != 0
-        msg: "{{ item }} must be present in {{ tempest_log_dir }}"
+        msg: "{{ item.item }} must be present in {{ tempest_log_dir }} and not empty"
-      with_items:
+      with_items: "{{ _results_list.results }}"
-        - "testr_results.html"
-        - "tempest_results.xml"
-        - "testrepository.subunit"
 
   vars_files:
     - common/test-vars.yml