.travis.yml: Require mobans are in sync on master

Author: jayvdb

.ci/check_moban.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+set -ex
+
+: "${MOBAN_BRANCH:=master}"
+
+git clone https://gitlab.com/coala/mobans \
+          --branch=${MOBAN_BRANCH} ../coala-mobans
+
+moban
+git diff --exit-code

.travis.yml

@@ -9,6 +9,26 @@ cache:
 script:
   - make html SPHINXOPTS=-W
 
+.check_moban_master: &check_moban_master
+  python: 3.6
+  stage: moban
+  install: pip install moban
+  script: .ci/check_moban.sh
+  if: branch = master AND type != pull_request
+
+.check_moban_other: &check_moban_other
+  <<: *check_moban_master
+  if: branch != master OR type = pull_request
+
+# env forces jobs to be created from the top level settings
+env:
+jobs:
+  include:
+    - *check_moban_master
+    - *check_moban_other
+  allow_failures:
+    - *check_moban_other
+
 notifications:
   email: false
   webhooks: https://www.travisbuddy.com/