Merge ~xavpaice/charm-grafana:fix_unit_tests_ci into charm-grafana:master

[Xav Paice]

Change list of packages tested in unit tests

Reduces the list of packages used for testing the package version
getting method, to packages that we are sure are installed in the test
environment.

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

This merge proposal is being monitored by mergebot. Change the status to Approved to merge.

[🤖 prod-jenkaas-bootstack (prod-jenkaas-bootstack)]

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[🤖 prod-jenkaas-bootstack (prod-jenkaas-bootstack)]

FAILED: Continuous integration, rev:1d72c2e5797cd27eaca7d6f5ee1b6e64898cf13c
https://jenkins.canonical.com/bootstack/job/lp-charm-grafana-ci/18/
Executed test runs:
    FAILURE: https://jenkins.canonical.com/bootstack/job/lp-charm-test-unit-withcompiler/48/
    None: https://jenkins.canonical.com/bootstack/job/lp-update-mp/230/

Click here to trigger a rebuild:
https://jenkins.canonical.com/bootstack/job/lp-charm-grafana-ci/18//rebuild

review: Needs Fixing (continuous-integration)

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[🤖 prod-jenkaas-bootstack (prod-jenkaas-bootstack)]

PASSED: Continuous integration, rev:cf8429a3add01f14f4fa5dc781f48988cc46a867
https://jenkins.canonical.com/bootstack/job/lp-charm-grafana-ci/19/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/bootstack/job/lp-charm-test-unit-withcompiler/49/
    None: https://jenkins.canonical.com/bootstack/job/lp-update-mp/231/

Click here to trigger a rebuild:
https://jenkins.canonical.com/bootstack/job/lp-charm-grafana-ci/19//rebuild

review: Approve (continuous-integration)

[🤖 prod-jenkaas-bootstack (prod-jenkaas-bootstack)]

A CI job is currently in progress. A follow up comment will be added when it completes.

[Celia Wang (ziyiwang)]

LGTM

review: Approve

[🤖 prod-jenkaas-bootstack (prod-jenkaas-bootstack)]

PASSED: Continuous integration, rev:cf8429a3add01f14f4fa5dc781f48988cc46a867
https://jenkins.canonical.com/bootstack/job/lp-charm-grafana-ci/20/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/bootstack/job/lp-charm-test-unit-withcompiler/50/
    None: https://jenkins.canonical.com/bootstack/job/lp-update-mp/232/

Click here to trigger a rebuild:
https://jenkins.canonical.com/bootstack/job/lp-charm-grafana-ci/20//rebuild

review: Approve (continuous-integration)

[Alvaro Uria (aluria)]

This test checks the get_installed_package_version function. The test runs "apt list --installed" and the tested function uses "apt-cache policy" and looks for the "Installed: <version>" line.

Since both tox and python3 are installed via apt (to run jobs in jenkins), I think this test looks good.

Thanks.

review: Approve

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

Change successfully merged at revision bd7473c7a624719123a45a3e1571b390a3ad2954

diff --git a/src/tests/unit/test_grafana.py b/src/tests/unit/test_grafana.py
index b0936c9..2645b53 100644
--- a/src/tests/unit/test_grafana.py
+++ b/src/tests/unit/test_grafana.py
@@ -26,14 +26,10 @@ class GrafanaTestCase(unittest.TestCase):
 
     def test_get_installed_package_version(self):
         """Test get_installed_package_version with basic packages."""
-        # these packages are installed by layer:basic
+        # these packages are sure to be installed or we can't run tests
         packages = [
-            "python3-pip",
-            "python3-setuptools",
-            "python3-yaml",
-            "python3-dev",
-            "python3-wheel",
-            "build-essential",
+            "python3",
+            "tox",
         ]
         for package in packages:
             # get the version with a different cmd