[polari/ci-test] ci: Check for issue/MR URLs in commit messages

[Florian Müllner <fmuellner src gnome org>]

commit d5880a1124d0579b31ffe8d1107b3b58311abd2d
Author: Florian Müllner <fmuellner gnome org>
Date:   Thu Feb 14 21:12:59 2019 +0100

    ci: Check for issue/MR URLs in commit messages
    
    Commit messages should include the full URL to an issue or merge
    request to keep associated information easily available in future
    log digging.
    
    Jonas came up with a script to enforce that policy for mutter and
    gnome-shell. It's an excellent idea, so adopt it here as well.
    
    https://gitlab.gnome.org/GNOME/polari/merge_requests/89

 .gitlab-ci.yml                 | 19 +++++++++++++++++++
 .gitlab-ci/check-commit-log.sh | 31 +++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index bfa05ab..cf9da17 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,5 @@
 stages:
+ - commit_check
  - source_check
  - build
  - review
@@ -7,11 +8,26 @@ variables:
     BUNDLE: "polari-git.flatpak"
     LINT_LOG: "eslint-report.txt"
 
+.only_default: &only_default
+    only:
+        - branches
+        - tags
+        - merge_requests
+
+check_commit_log:
+    image: registry.gitlab.gnome.org/gnome/gjs:fedora.static-analysis
+    stage: commit_check
+    script:
+        - ./.gitlab-ci/check-commit-log.sh
+    only:
+        - merge_requests
+
 eslint:
     image: registry.gitlab.gnome.org/gnome/gjs:fedora.static-analysis
     stage: source_check
     script:
         - sh lint/generate-report.sh -o $LINT_LOG || { cat $LINT_LOG; false; }
+    <<: *only_default
     artifacts:
         paths:
             - ${LINT_LOG}
@@ -46,6 +62,7 @@ flatpak:
         - flatpak build-bundle repo ${BUNDLE} --runtime-repo=${RUNTIME_REPO} ${DBUS_ID} ${BRANCH}
     after_script:
         - tar -czf cache.tar.gz .flatpak-builder/cache
+    <<: *only_default
 
     artifacts:
         paths:
@@ -64,6 +81,7 @@ review:
         - flatpak
     script:
         - echo "Generating flatpak deployment"
+    <<: *only_default
     artifacts:
         paths:
             - ${BUNDLE}
@@ -81,6 +99,7 @@ stop_review:
     stage: review
     script:
         - echo "Stopping flatpak deployment"
+    <<: *only_default
     when: manual
     environment:
         name: review/$CI_COMMIT_REF_NAME
diff --git a/.gitlab-ci/check-commit-log.sh b/.gitlab-ci/check-commit-log.sh
new file mode 100755
index 0000000..cc3bcee
--- /dev/null
+++ b/.gitlab-ci/check-commit-log.sh
@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+
+if [ -z "$CI_MERGE_REQUEST_TARGET_BRANCH_NAME" ]; then
+  echo Cannot review non-merge request
+  exit 1
+fi
+
+git fetch $CI_MERGE_REQUEST_PROJECT_URL.git $CI_MERGE_REQUEST_TARGET_BRANCH_NAME
+
+branch_point=$(git merge-base HEAD FETCH_HEAD)
+
+commits=$(git log --format='format:%H' $branch_point..$CI_COMMIT_SHA)
+
+if [ -z "$commits" ]; then
+  echo Commit range empty
+  exit 1
+fi
+
+function commit_message_has_url() {
+  commit=$1
+  commit_message=$(git show -s --format='format:%b' $commit)
+  echo "$commit_message" | grep -qe 
"\($CI_MERGE_REQUEST_PROJECT_URL/\(issues\|merge_requests\)/[0-9]\+\|https://bugzilla.gnome.org/show_bug.cgi?id=[0-9]\+\)"
+  return $?
+}
+
+for commit in $commits; do
+  if ! commit_message_has_url $commit; then
+    echo "Missing merge request or issue URL on commit $(echo $commit | cut -c -8)"
+    exit 1
+  fi
+done