SCM repo: add reset-first option

Change-Id: Iafb79bb98ac3863f996027caa9136725cc59e973
Signed-off-by: Lucas Dutra Nunes <ldnunes@ossystems.com.br>

jenkins_jobs/modules/scm.py

@@ -579,6 +579,9 @@ def repo(parser, xml_parent, data):
         recent commit (default 0)
     :arg bool current-branch: Fetch only the current branch from the server
         (default true)
+    :arg bool reset-first: Remove any commits that are not on the repositories
+        by running the following command before anything else (default false):
+        ``repo forall -c "git reset --hard"``
     :arg bool quiet: Make repo more quiet
         (default true)
     :arg bool force-sync: Continue sync even if a project fails to sync
@@ -611,6 +614,7 @@ def repo(parser, xml_parent, data):
         ("jobs", 'jobs', 0),
         ("depth", 'depth', 0),
         ("current-branch", 'currentBranch', True),
+        ("reset-first", 'resetFirst', False),
         ("quiet", 'quiet', True),
         ("force-sync", 'forceSync', False),
         ("local-manifest", 'localManifest', ''),

tests/macros/fixtures/scm/multi-scms002.xml

@@ -21,6 +21,7 @@
         <jobs>3</jobs>
         <depth>2</depth>
         <currentBranch>false</currentBranch>
+        <resetFirst>false</resetFirst>
         <quiet>false</quiet>
         <forceSync>false</forceSync>
       </scm>

tests/scm/fixtures/repo001.xml

@@ -11,6 +11,7 @@
     <jobs>3</jobs>
     <depth>0</depth>
     <currentBranch>false</currentBranch>
+    <resetFirst>true</resetFirst>
     <quiet>false</quiet>
     <forceSync>true</forceSync>
     <localManifest>&lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;

tests/scm/fixtures/repo001.yaml

@@ -9,6 +9,7 @@ scm:
       mirror-dir: ~/git/project/
       jobs: 3
       current-branch: false
+      reset-first: true
       quiet: false
       force-sync: true
       local-manifest: |