links to source: get refname from version string

So it's no longer necessary to provide the REFNAME environment variable.
Also the link template string format is now more general to support at
least gitlab github and cgit.

.gitlab-ci.yml

@@ -38,7 +38,7 @@ check for dependencies installed:
 build documentation:
   stage: test
   script:
-    - make -C doc realclean; make -C doc html SPHINXOPTS='-A website_deploy=True -n -W' REFNAME="${CI_COMMIT_TAG:-$CI_COMMIT_SHA}" SOURCE_URL="$CI_PROJECT_URL"/blob
+    - make -C doc realclean; make -C doc html SPHINXOPTS='-A website_deploy=True -n -W' SOURCE_LINK_TEMPLATE="$CI_PROJECT_URL"/blob/$$r/$$f
   artifacts:
     paths:
       - doc/build/html/

RELEASE.rst

@@ -112,7 +112,7 @@ Building the documentation requires 'sphinx' and a Latex installation.
 First build the HTML and PDF documentation::
 
     ./setup.py build
-    make -C doc realclean html latex SPHINXOPTS='-A website_deploy=True -n -W' REFNAME="<version>"
+    make -C doc realclean html latex SPHINXOPTS='-A website_deploy=True -n -W'
     cd doc/build/latex
     make all-pdf
 

doc/source/conf.py

@@ -11,8 +11,9 @@
 # All configuration values have a default; values that are commented out
 # serve to show the default.
 
-import sys, os
-
+import sys
+import os
+import string
 from distutils.util import get_platform
 sys.path.insert(0, "../../build/lib.{0}-{1}.{2}".format(
         get_platform(), *sys.version_info[:2]))
@@ -298,8 +299,18 @@ def linkcode_resolve(domain, info):
         filename = 'kwant/%s#L%d-%d' % find_source()
     except Exception:
         filename = info['module'].replace('.', '/') + '.py'
-    source_branch = os.environ.get('REFNAME', 'master')
-    url = os.environ.get('SOURCE_URL',
-                         "https://gitlab.kwant-project.org/kwant/kwant/blob")
 
-    return "{}/{}/{}".format(url, source_branch, filename)
+    # The following relies on the documented format of kwant.__version__.
+    rel = release.rstrip('.dirty')
+    if '.dev' in rel:
+        try:
+            refname = rel[rel.index('+g') + 2:]
+        except ValueError:
+            return
+    else:
+        refname = 'v' + rel
+
+    templ = os.environ.get(
+        "SOURCE_LINK_TEMPLATE",
+        "https://gitlab.kwant-project.org/kwant/kwant/blob/$r/$f")
+    return string.Template(templ).safe_substitute(r=refname, f=filename)