Changelog: Fix CI job and introduce verification CI job (#278)

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<!-- Remember to modify the changelog. If you don't need to modify it,
you can check the following box.
Instead, if you have already modified it, simply delete the following
line. -->

- [x] Does not require a CHANGELOG entry

.github/changelog-processor.py

@@ -32,12 +32,39 @@
     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.strip().removeprefix("## [").split("]")[0].count(".") != 2 and not "unreleased" in line.lower():
+                    print("Only Major.Minor.Patch are supported as versioning")
+                    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 +80,6 @@
         else:
             break
 
-
     if args.changelog_last_release:
         print(changelog_last_release, end = "")
         sys.exit(0)
@@ -63,7 +89,7 @@
     elif args.should_release:
         if version.lower() == "unreleased":
             print("0", end = "")
-            sys.exit(-1)
+            sys.exit(0)
         elif version.count(".") != 2:
             print("0", end = "")
             sys.exit(-1)

.github/workflows/changelog.yml

@@ -1,14 +1,22 @@
-name: Modify Changelog
+name: Verify Changelog
+
+# If you modify more test jobs, ensure that you add them as required to the job "confirmTestPassed"
+# which is located at the end of this file (more info in the job)
 
 on:
-  pull_request_target:
-    types:
-      - synchronize
-      - edited
+  push:
+    branches: ["main", "release-*"]
+  pull_request:
+  workflow_dispatch:
+
+# cancel previous runs
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
 
 jobs:
 
-  verifyChangelog:
+  verify-changelog-updated:
     name: Verify that Changelog is Updated
     runs-on: ubuntu-latest
     env:
@@ -22,3 +30,29 @@ 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: Checkout sources
+        uses: actions/checkout@v3
+
+      - name: Verify
+        run: .github/changelog-processor.py CHANGELOG.md --validate-changelog
+
+  # This will only run if all the tests in its "needs" array passed.
+  # Add this as your required job, becuase if the matrix changes size (new things get added)
+  # it will still require all the steps to succeed.
+  # If you add more jobs, remember to add them to the "needs" array.
+  confirmChangelogChecksPassed:
+    runs-on: ubuntu-latest
+    name: All tests passed
+    # If any new job gets added, be sure to add it to this list
+    needs:
+      - verify-changelog-updated
+      - verify-changelog-valid
+    steps:
+      - run: echo '### Good job! All the tests passed 🚀' >> $GITHUB_STEP_SUMMARY

.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

CHANGELOG.md

@@ -4,7 +4,7 @@ Changelog for the runtimes governed by the Polkadot Fellowship.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
-## Unreleased
+## [Unreleased]
 
 ### Changed