Handle WIP Gerrit status

Newer versions of Gerrit have a built-in work-in-progress flag
which, when set, makes the change unsubmittable.  Update the
canMerge method in the Gerrit driver to recognize the new flag.

Change-Id: Ia8e5e50086933215c45e92b419a04c1117880a34

tests/base.py

@@ -1,5 +1,6 @@
 # Copyright 2012 Hewlett-Packard Development Company, L.P.
 # Copyright 2016 Red Hat, Inc.
+# Copyright 2021 Acme Gating, LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain
@@ -638,6 +639,14 @@ class FakeGerritChange(object):
         self.data['submitRecords'] = self.getSubmitRecords()
         return json.loads(json.dumps(event))
 
+    def setWorkInProgress(self, wip):
+        # Gerrit only includes 'wip' in the data returned via ssh if
+        # the value is true.
+        if wip:
+            self.data['wip'] = True
+        elif 'wip' in self.data:
+            del self.data['wip']
+
     def getSubmitRecords(self):
         status = {}
         for cat in self.categories:
@@ -770,7 +779,8 @@ class FakeGerritChange(object):
             "labels": labels,
             "current_revision": self.patchsets[-1]['revision'],
             "revisions": revisions,
-            "requirements": []
+            "requirements": [],
+            "work_in_progresss": self.data.get('wip', False)
         }
         return json.loads(json.dumps(data))
 

tests/unit/test_scheduler.py

@@ -1249,6 +1249,10 @@ class TestScheduler(ZuulTestCase):
         a = source.getChange(event, refresh=True)
         self.assertTrue(source.canMerge(a, mgr.getSubmitAllowNeeds()))
 
+        A.setWorkInProgress(True)
+        a = source.getChange(event, refresh=True)
+        self.assertFalse(source.canMerge(a, mgr.getSubmitAllowNeeds()))
+
     def test_project_merge_conflict(self):
         "Test that gate merge conflicts are handled properly"
 

zuul/driver/gerrit/gerritconnection.py

@@ -966,6 +966,8 @@ class GerritConnection(BaseConnection):
             # Good question.  It's probably ref-updated, which, ah,
             # means it's merged.
             return True
+        if change.wip:
+            return False
         if change.missing_labels <= set(allow_needs):
             return True
         return False

zuul/driver/gerrit/gerritmodel.py

@@ -32,6 +32,7 @@ class GerritChange(Change):
     def __init__(self, project):
         super(GerritChange, self).__init__(project)
         self.status = None
+        self.wip = None
         self.approvals = []
 
     def update(self, data, connection):
@@ -79,6 +80,7 @@ class GerritChange(Change):
         self.approvals = data['currentPatchSet'].get('approvals', [])
         self.open = data['open']
         self.status = data['status']
+        self.wip = data.get('wip', False)
         self.owner = data['owner'].get('username')
         self.message = data['commitMessage']
 
@@ -149,6 +151,7 @@ class GerritChange(Change):
             self.missing_labels.add(label_name)
         self.open = data['status'] == 'NEW'
         self.status = data['status']
+        self.wip = data.get('work_in_progress', False)
         self.owner = data['owner'].get('username')
         self.message = current_revision['commit']['message']