CI: doc in branch name triggers make doc-html

.gitlab-ci.yml

@@ -507,6 +507,20 @@ pages:
   tags:
     - gitlab-org
 
+documentation:
+  image: ${build_deps_image}:${CI_COMMIT_SHA}
+  stage: test
+  only:
+    - /^.*doc.*$/
+  script:
+    - sudo apk add --no-cache py3-sphinx py3-sphinx_rtd_theme
+    - sudo ln -s /usr/bin/sphinx-build-3 /usr/bin/sphinx-build
+    - opam install --yes odoc
+    - make doc-html
+  tags:
+    - gitlab-org
+
+
 ## Relaunching the bootstrap servers of the alphanet.zeronet
 
 .bootstrap_template: &bootstrap_definition

docs/introduction/contributing.rst

@@ -79,4 +79,11 @@ As per the hygiene of MRs themselves:
 -  Give appropriate titles to the MRs, and when non trivial add a
    detailed motivated explanation.
 -  Give meaningful and consistent names to branches.
--  Don’t forget to put a ``WIP:`` flag when it is a work in progress.
+-  Don’t forget to put a ``WIP:`` flag when it is a work in progress
+
+Some extra CI tests are only done on demand for branches other that
+master. You can (should) activate these tests by including keywords in
+the branch name.
+
+-  If your MR impacts OPAM packaging, use ``opam`` in the branch name.
+-  If your MR updates documentation, use ``doc`` in the branch name.