Fix release notes generation even if no new version is detected

gitdch

@@ -227,14 +227,6 @@ if not options.quiet or not options.logfile:
 
 repo = git.Repo(options.git_path)
 
-log.info('Generate changelog from git commits')
-
-versions = []
-tag_commits = dict(
-    (tag.commit.binsha, tag)
-    for tag in repo.tags
-)
-
 
 def clean_deb_version(version_name):
     """ Clean debian version name """
@@ -246,6 +238,21 @@ def clean_deb_version(version_name):
     return version_name
 
 
+if not options.version:
+    log.info('Detect current version from git tags & commits')
+    options.version = clean_deb_version(
+        repo.git.describe('--always', '--tags')
+    )
+    log.info('Currrent version detected: %s', options.version)
+log.info('Generate changelog from git commits')
+
+versions = []
+tag_commits = dict(
+    (tag.commit.binsha, tag)
+    for tag in repo.tags
+)
+
+
 def add_version():
     """ Add version info """
     global messages  # pylint: disable=global-statement
@@ -264,12 +271,7 @@ def add_version():
 
 tag = None
 version_commit = None
-version = (
-    options.version or
-    clean_deb_version(
-        repo.git.describe('--always', '--tags')
-    )
-)
+version = options.version
 messages = []
 for commit in repo.iter_commits(rev=options.revision):
     log.debug('Commit %s (%s)', commit, commit.summary)
@@ -350,10 +352,15 @@ else:
 if options.release_notes:
     log.info('Generate Markdown release notes')
     release_notes_lines = ['# Changelog:\n\n']
+    if versions:
         release_notes_lines.extend([
             '* {0}\n'.format(message)
             for message in versions[0]['messages']
         ])
+    else:
+        release_notes_lines.extend([
+            '* Release version {0}\n'.format(options.version)
+        ])
     log.info(
         'Write generated Markdown release notes in file %s',
         options.release_notes)