From 2ec590b606e577b0b96c895426d73c57b2b3b4d0 Mon Sep 17 00:00:00 2001
From: "James E. Blair" <jeblair@redhat.com>
Date: Wed, 24 May 2017 13:59:17 -0700
Subject: [PATCH] Check out the appropriate branch in executor

This mimics the behavior of Zuul cloner and allows the user to
specify what branches of each repo should be checked out in the
jobdir at the start of the job.

(Of course, the job is free to check out other branches as needed;
all of them will have the appropriate future state.)

Change-Id: I93af5c49cb0404944636c7e63d203cdb564b267c
---
 zuul/executor/client.py |  4 ++++
 zuul/executor/server.py | 33 +++++++++++++++++++++++++++++++++
 zuul/merger/merger.py   |  4 ++++
 3 files changed, 41 insertions(+)

diff --git a/zuul/executor/client.py b/zuul/executor/client.py
index 1d9cd72434..5a1820e4d3 100644
--- a/zuul/executor/client.py
+++ b/zuul/executor/client.py
@@ -261,6 +261,10 @@ class ExecutorClient(object):
         params['timeout'] = job.timeout
         params['items'] = merger_items
         params['projects'] = []
+        if hasattr(item.change, 'branch'):
+            params['branch'] = item.change.branch
+        else:
+            params['branch'] = None
         params['override_branch'] = job.override_branch
         params['repo_state'] = item.current_build_set.repo_state
 
diff --git a/zuul/executor/server.py b/zuul/executor/server.py
index e175fbf618..b3dc9f2778 100644
--- a/zuul/executor/server.py
+++ b/zuul/executor/server.py
@@ -587,6 +587,15 @@ class AnsibleJob(object):
                 # a work complete result, don't run any jobs
                 return
 
+        for project in args['projects']:
+            repo = repos[project['canonical_name']]
+            self.checkoutBranch(repo,
+                                project['name'],
+                                args['branch'],
+                                args['override_branch'],
+                                project['override_branch'],
+                                project['default_branch'])
+
         # Delete the origin remote from each repo we set up since
         # it will not be valid within the jobs.
         for repo in repos.values():
@@ -641,6 +650,30 @@ class AnsibleJob(object):
             repo.setRef('refs/heads/' + branch, commit)
         return True
 
+    def checkoutBranch(self, repo, project_name, zuul_branch,
+                       job_branch, project_override_branch,
+                       project_default_branch):
+        branches = repo.getBranches()
+        if project_override_branch in branches:
+            self.log.info("Checking out %s project override branch %s",
+                          project_name, project_override_branch)
+            repo.checkoutLocalBranch(project_override_branch)
+        elif job_branch in branches:
+            self.log.info("Checking out %s job branch %s",
+                          project_name, job_branch)
+            repo.checkoutLocalBranch(job_branch)
+        elif zuul_branch and zuul_branch in branches:
+            self.log.info("Checking out %s zuul branch %s",
+                          project_name, zuul_branch)
+            repo.checkoutLocalBranch(zuul_branch)
+        elif project_default_branch in branches:
+            self.log.info("Checking out %s project default branch %s",
+                          project_name, project_default_branch)
+            repo.checkoutLocalBranch(project_default_branch)
+        else:
+            raise Exception("Project %s does not have the default branch %s" %
+                            (project_name, project_default_branch))
+
     def runPlaybooks(self, args):
         result = None
 
diff --git a/zuul/merger/merger.py b/zuul/merger/merger.py
index 4df24aa7db..b0183d0bf9 100644
--- a/zuul/merger/merger.py
+++ b/zuul/merger/merger.py
@@ -134,6 +134,10 @@ class Repo(object):
         origin = repo.remotes.origin
         return branch in origin.refs
 
+    def getBranches(self):
+        repo = self.createRepoObject()
+        return [x.name for x in repo.heads]
+
     def getCommitFromRef(self, refname):
         repo = self.createRepoObject()
         if refname not in repo.refs: