Merge ~ogayot/curtin:deb822-no-suite-stanza into curtin:master

[Olivier Gayot]

apt_source: do not produce a deb822 source stanza with zero suite

When no suite is set for a given repository, we end up with a
deb822 styled source such as:

 Type: deb
 Suites:
 URIs: http://archive.ubuntu.com/ubuntu

This is invalid and apt/apt-get will raise the following error:

E: Malformed entry 2 in sources file
 /etc/apt/sources.list.d/ubuntu.sources (Suite)

Signed-off-by: Olivier Gayot <email address hidden>

Prevent creation of invalid deb822 source when no suite is configured.

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:d3b6443f3d34e1bd9ce4337b5be3a495edd10a43
https://jenkins.canonical.com/server-team/job/curtin-ci/195/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-amd64/195/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-arm64/195/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-ppc64el/195/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-s390x/195/

Click here to trigger a rebuild:
https://jenkins.canonical.com/server-team/job/curtin-ci/195//rebuild

review: Approve (continuous-integration)

[Dan Bungert (dbungert)]

Same, unit test please. Thanks!

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:5b954a96ca8006c939f161cc62cf29faeb6b034a
https://jenkins.canonical.com/server-team/job/curtin-ci/196/
Executed test runs:
    FAILURE: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-amd64/196/
    FAILURE: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-arm64/196/
    FAILURE: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-ppc64el/196/
    FAILURE: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-s390x/196/

Click here to trigger a rebuild:
https://jenkins.canonical.com/server-team/job/curtin-ci/196//rebuild

review: Needs Fixing (continuous-integration)

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:29b3faf7c30eea08e5a955d9a9fbe3a32846e314
https://jenkins.canonical.com/server-team/job/curtin-ci/197/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-amd64/197/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-arm64/197/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-ppc64el/197/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-s390x/197/

Click here to trigger a rebuild:
https://jenkins.canonical.com/server-team/job/curtin-ci/197//rebuild

review: Approve (continuous-integration)

[Server Team CI bot (server-team-bot)]

Commit message lints:
- Line #11 has 9 too many characters. Line starts with: "E: Malformed entry 2"...

review: Needs Fixing

[Server Team CI bot (server-team-bot)]

review: Approve (continuous-integration)

diff --git a/curtin/commands/apt_config.py b/curtin/commands/apt_config.py
index f045163..d2a12d5 100644
--- a/curtin/commands/apt_config.py
+++ b/curtin/commands/apt_config.py
@@ -638,6 +638,11 @@ def _generate_sources_deb822(cfg, release, mirrors, target=None, arch=None):
         entry['Suites'] = list(set(entry['Suites']) - suites_to_disable)
         entry['Components'] = list(set(entry['Components']) - comps_to_disable)
 
+        if not entry['Suites']:
+            # It is invalid for a stanza to have zero suite configured. In
+            # practise, it can happen when -security is disabled.
+            continue
+
         stanzas.append(deb822_entry_to_str(entry))
 
     target_path = paths.target_path(target, sources_deb822)
diff --git a/tests/unittests/test_apt_source.py b/tests/unittests/test_apt_source.py
index 6322879..8146c68 100644
--- a/tests/unittests/test_apt_source.py
+++ b/tests/unittests/test_apt_source.py
@@ -1306,7 +1306,14 @@ deb-src http://ubuntu.com//ubuntu xenial universe multiverse
             'etc/apt/sources.list.d/ubuntu.sources': ((
                 'Types: deb\n'
                 'URIs: $MIRROR\n'
-                'Suites: $RELEASE $RELEASE-updates $RELEASE-backports\n'
+                'Suites: $RELEASE $RELEASE-updates\n'
+                'components: main\n'
+                'signed-by: /usr/share/keyrings/ubuntu-archive-keyring.gpg\n'
+                '\n'
+                # This section should be skipped because -backports is disabled
+                'Types: deb\n'
+                'URIs: $MIRROR\n'
+                'Suites: $RELEASE-backports\n'
                 'components: main\n'
                 'signed-by: /usr/share/keyrings/ubuntu-archive-keyring.gpg\n'
                 '\n'