Changelog: Fix CI job and introduce verification CI job

.github/changelog-processor.py

@@ -32,12 +32,35 @@
     help="Print the changelog from the last release.",
     action="store_true"
 )
+group.add_argument(
+    "--validate-changelog",
+    dest="validate_changelog",
+    help="Validates that the changelog uses the correct syntax",
+    action="store_true"
+)
 
 args = parser.parse_args()
 
 with open(args.changelog, "r") as changelog:
     lines = changelog.readlines()
 
+    if args.validate_changelog:
+        for line in lines:
+            if line.startswith("##"):
+                if line.startswith("###"):
+                    continue
+                elif not line.startswith("## ["):
+                    print("Line starting with `##` needs to be followed by ` [`, e.g.: `## [Unreleased]`, `## [400.2.1]`")
+                    print(line)
+                    sys.exit(-1)
+            elif line.startswith("#"):
+                if line.strip() != "# Changelog":
+                    print("Line starting with `#` is only allowed for `# Changelog`")
+                    print(line)
+                    sys.exit(-1)
+
+        sys.exit(0)
+
     changelog_last_release = ""
     found_last_version = False
 
@@ -53,7 +76,6 @@
         else:
             break
 
-
     if args.changelog_last_release:
         print(changelog_last_release, end = "")
         sys.exit(0)

.github/workflows/changelog.yml

@@ -1,4 +1,4 @@
-name: Modify Changelog
+name: Verify Changelog
 
 on:
   pull_request_target:
@@ -8,7 +8,7 @@ on:
 
 jobs:
 
-  verifyChangelog:
+  verify-changelog-updated:
     name: Verify that Changelog is Updated
     runs-on: ubuntu-latest
     env:
@@ -22,3 +22,12 @@ jobs:
       - name: Set error
         if: steps.changed.outputs.matched != 'true' && !contains(github.event.pull_request.body, '[x] Does not require a CHANGELOG entry')
         run: echo "::error::CHANGELOG.md has not been modified. Either modify the file or check the checkbox in the body" && exit 1
+
+  verify-changelog-valid:
+    name: Verify that Changelog is valid
+    runs-on: ubuntu-latest
+    env:
+      GITHUB_TOKEN: ${{ github.token }}
+    steps:
+      - name: Verify
+        run: .github/changelog-processor.py CHANGELOG.md --validate-changelog

.github/workflows/check-migrations.yml

@@ -65,7 +65,8 @@ jobs:
           fi
 
           # Disable the spec version check when we dont want to release.
-          if ! .github/changelog-processor.py CHANGELOG.md --should-release ; then
+          # The program prints either `1` or `0`.
+          if [ "$(.github/changelog-processor.py CHANGELOG.md --should-release)" = "0" ]; then
             EXTRA_FLAGS+=" --disable-spec-version-check"
             echo "Disabling the spec version check since we are not releasing"
           else