[pinpoint] Limit executions to one test run each + device sharding.

dashboard/dashboard/pinpoint/models/quest/run_test_test.py

Index: dashboard/dashboard/pinpoint/models/quest/run_test_test.py
diff --git a/dashboard/dashboard/pinpoint/models/quest/run_test_test.py b/dashboard/dashboard/pinpoint/models/quest/run_test_test.py
index 55513d0708e8fe027350bbaf027a6b3161145d3c..41889dbc36bfe71bfbfe44724fe1def2f842cf11 100644
--- a/dashboard/dashboard/pinpoint/models/quest/run_test_test.py
+++ b/dashboard/dashboard/pinpoint/models/quest/run_test_test.py
@@ -73,7 +73,7 @@ class RunTestFullTest(_RunTestTest):
 
     # Call RunTest.Start() to create an Execution.
     quest = run_test.RunTest(_SWARMING_DIMENSIONS, _SWARMING_EXTRA_ARGS)
-    execution = quest.Start('input isolate hash')
+    execution = quest.Start('change_1', 'input isolate hash')
 
     swarming_task_result.assert_not_called()
     swarming_tasks_new.assert_not_called()
@@ -83,7 +83,7 @@ class RunTestFullTest(_RunTestTest):
     execution.Poll()
 
     swarming_task_result.assert_not_called()
-    swarming_tasks_new.assert_called_once()
+    self.assertEqual(swarming_tasks_new.call_count, 1)
     self.assertNewTaskHasDimensions(swarming_tasks_new)
     self.assertFalse(execution.completed)
     self.assertFalse(execution.failed)
@@ -108,25 +108,30 @@ class RunTestFullTest(_RunTestTest):
     self.assertFalse(execution.failed)
     self.assertEqual(execution.result_values, (None,))
     self.assertEqual(execution.result_arguments,
-                     {'isolate_hashes': ('output isolate hash',)})
+                     {'isolate_hash': 'output isolate hash'})
     self.assertEqual(
         {
-            'bot_ids': ['bot id'],
+            'bot_id': 'bot id',
             'input_isolate_hash': 'input isolate hash',
-            'task_ids': ['task id'],
-            'result_arguments': {'isolate_hashes': ('output isolate hash',)},
+            'task_id': 'task id',
+            'result_arguments': {'isolate_hash': 'output isolate hash'},
             'result_values': (None,),
         },
         execution.AsDict())
 
-
-    # Start a second Execution to check bot_id handling. We get a bot_id from
-    # Swarming from the first Execution and reuse it in subsequent Executions.
-    execution = quest.Start('input isolate hash')
+    # Start a second Execution on another Change. It should use the bot_id
+    # from the first execution.
+    execution = quest.Start('change_2', 'input isolate hash')
     execution.Poll()
 
     self.assertNewTaskHasBotId(swarming_tasks_new)
 
+    # Start an Execution on the same Change. It should use a new bot_id.
+    execution = quest.Start('change_2', 'input isolate hash')
+    execution.Poll()
+
+    self.assertNewTaskHasDimensions(swarming_tasks_new)
+
 
 @mock.patch('dashboard.services.swarming_service.Tasks.New')
 @mock.patch('dashboard.services.swarming_service.Task.Result')
@@ -137,7 +142,7 @@ class SwarmingTaskStatusTest(_RunTestTest):
     swarming_tasks_new.return_value = {'task_id': 'task id'}
 
     quest = run_test.RunTest(_SWARMING_DIMENSIONS, _SWARMING_EXTRA_ARGS)
-    execution = quest.Start('input isolate hash')
+    execution = quest.Start(None, 'input isolate hash')
     execution.Poll()
     execution.Poll()
 
@@ -158,7 +163,7 @@ class SwarmingTaskStatusTest(_RunTestTest):
     swarming_tasks_new.return_value = {'task_id': 'task id'}
 
     quest = run_test.RunTest(_SWARMING_DIMENSIONS, _SWARMING_EXTRA_ARGS)
-    execution = quest.Start('isolate_hash')
+    execution = quest.Start(None, 'isolate_hash')
     execution.Poll()
     execution.Poll()
 
@@ -184,7 +189,7 @@ class BotIdHandlingTest(_RunTestTest):
     swarming_task_result.return_value = {'state': 'EXPIRED'}
 
     quest = run_test.RunTest(_SWARMING_DIMENSIONS, _SWARMING_EXTRA_ARGS)
-    execution = quest.Start('input isolate hash')
+    execution = quest.Start('change_1', 'input isolate hash')
     execution.Poll()
     execution.Poll()
 
@@ -195,7 +200,7 @@ class BotIdHandlingTest(_RunTestTest):
         'outputs_ref': {'isolated': 'output isolate hash'},
         'state': 'COMPLETED',
     }
-    execution = quest.Start('input isolate hash')
+    execution = quest.Start('change_2', 'input isolate hash')
     execution.Poll()
 
     self.assertTrue(execution.completed)
@@ -210,8 +215,8 @@ class BotIdHandlingTest(_RunTestTest):
     # Executions after the first must wait for the first execution to get a bot
     # ID. To preserve device affinity, they must use the same bot.
     quest = run_test.RunTest(_SWARMING_DIMENSIONS, _SWARMING_EXTRA_ARGS)
-    execution_1 = quest.Start('input isolate hash')
-    execution_2 = quest.Start('input isolate hash')
+    execution_1 = quest.Start('change_1', 'input isolate hash')
+    execution_2 = quest.Start('change_2', 'input isolate hash')
 
     swarming_tasks_new.return_value = {'task_id': 'task id'}
     swarming_task_result.return_value = {'state': 'PENDING'}