Improve test case test_unprotected_branches

We are missing facilities in the github fake to define the protected
branches of a repository. Add that and use it to improve the
test_unprotected_branches test case. This now additionally protects a
branch and triggers a reload to check if the branch is now loaded.

Change-Id: I183d4fbe2eddeb1c72fd696d797a75ae93293224

tests/fakegithub.py

@@ -27,8 +27,9 @@ class FakeUser(object):
 
 
 class FakeBranch(object):
-    def __init__(self, branch='master'):
+    def __init__(self, branch='master', protected=False):
         self.name = branch
+        self.protected = protected
 
 
 class FakeStatus(object):
@@ -78,9 +79,15 @@ class FakeRepository(object):
     def branches(self, protected=False):
         if protected:
             # simulate there is no protected branch
-            return []
+            return [b for b in self._branches if b.protected]
         return self._branches
 
+    def _set_branch_protection(self, branch_name, protected):
+        for branch in self._branches:
+            if branch.name == branch_name:
+                branch.protected = protected
+                return
+
     def _build_url(self, *args, **kwargs):
         path_args = ['repos', self.name]
         path_args.extend(args)

tests/fixtures/config/unprotected-branches/git/org_project2/zuul.yaml

@@ -1 +1,2 @@
-This zuul.yaml is intentionally broken and should not be loaded on startup.
+- job:
+    name: unused-job

tests/unit/test_github_driver.py

@@ -829,6 +829,21 @@ class TestGithubUnprotectedBranches(ZuulTestCase):
         # project2 should have no parsed branch
         self.assertEqual(0, len(tpc2.parsed_branch_config.keys()))
 
+        # now enable branch protection and trigger reload
+        github = self.fake_github.getGithubClient()
+        repo = github.repo_from_project('org/project2')
+        repo._set_branch_protection('master', True)
+        self.sched.reconfigure(self.config)
+        self.waitUntilSettled()
+
+        tenant = self.sched.abide.tenants.get('tenant-one')
+        tpc1 = tenant.project_configs[project1.canonical_name]
+        tpc2 = tenant.project_configs[project2.canonical_name]
+
+        # project1 and project2 should have parsed master now
+        self.assertIn('master', tpc1.parsed_branch_config.keys())
+        self.assertIn('master', tpc2.parsed_branch_config.keys())
+
 
 class TestGithubWebhook(ZuulTestCase):
     config_file = 'zuul-github-driver.conf'