Extract out a common mock task into a module.

The mock tasks are used in multiple unitest modules. It is not extracted out
into a module to enable reuse.

BUG=None
TEST=unit testing for the pipeline stage and pipeline workers.

Change-Id: Iee436266f7ea26c2877377f52208cc5cd31e7815
Reviewed-on: https://gerrit-int.chromium.org/41001
Reviewed-by: Simon Que <sque@google.com>
Reviewed-by: Luis Lozano <llozano@chromium.org>
Commit-Queue: Yuheng Long <yuhenglong@google.com>
Tested-by: Yuheng Long <yuhenglong@google.com>

1 files changed, 64 insertions, 0 deletions

diff --git a/bestflags/mock_task.py b/bestflags/mock_task.py
new file mode 100644
index 00000000..2582f111
--- /dev/null
+++ b/bestflags/mock_task.py
@@ -0,0 +1,64 @@
+"""This module defines the common mock task used by varies unit tests.
+
+Part of the Chrome build flags optimization.
+"""
+
+__author__ = 'yuhenglong@google.com (Yuheng Long)'
+
+# Pick an integer at random.
+POISONPILL = 975
+
+
+class MockTask(object):
+  """This class emulates an actual task.
+
+  It does not do the actual work, but simply returns the result as given when
+  this task is constructed.
+  """
+
+  def __init__(self, stage, identifier, cost=0):
+    """Set up the results for this task.
+
+    Args:
+      stage: the stage of this test is in.
+      identifier: the identifier of this task.
+      cost: the mock cost of this task.
+
+      The _pre_cost field stored the cost. Once this task is performed, i.e., by
+      calling the work method, the _cost field will have this cost. The stage
+      field verifies that the module being tested and the unitest are in the
+      same stage. If the unitest does not care about cost of this task, the cost
+      parameter should be leaved blank.
+    """
+
+    self._identifier = identifier
+    self._pre_cost = cost
+    self._stage = stage
+
+  def __eq__(self, other):
+    if isinstance(other, MockTask):
+      return (self._identifier == other.GetIdentifier(self._stage) and
+              self._cost == other.GetResult(self._stage))
+    return False
+
+  def GetIdentifier(self, stage):
+    assert stage == self._stage
+    return self._identifier
+
+  def SetResult(self, stage, cost):
+    assert stage == self._stage
+    self._cost = cost
+
+  def Work(self, stage):
+    assert stage == self._stage
+    self._cost = self._pre_cost
+
+  def GetResult(self, stage):
+    assert stage == self._stage
+    return self._cost
+
+  def Done(self, stage):
+    """Indicates whether the task has been performed."""
+
+    assert stage == self._stage
+    return '_cost' in self.__dict__