add unit test for --from-file option

Change-Id: If58e2dde86fc2ad85a254702dfc115c3ebc450c1
Signed-off-by: Young-Ho Cha <ganadist@gmail.com>
diff --git a/run_unittest.py b/run_unittest.py
index 4782073..66496ba 100755
--- a/run_unittest.py
+++ b/run_unittest.py
@@ -31,6 +31,7 @@
 TEST_DIR = 'test_data/'
 ATRACE_DATA = TEST_DIR + 'atrace_data'
 ATRACE_DATA_RAW = TEST_DIR + 'atrace_data_raw'
+ATRACE_DATA_RAW_FROM_FILE = TEST_DIR + 'atrace_data_raw_from_file'
 ATRACE_DATA_STRIPPED = TEST_DIR + 'atrace_data_stripped'
 ATRACE_DATA_THREAD_FIXED = TEST_DIR + 'atrace_data_thread_fixed'
 ATRACE_DATA_WITH_THREAD_LIST = TEST_DIR + 'atrace_data_with_thread_list'
@@ -113,6 +114,15 @@
     self.assertEqual(' '.join(TRACE_LIST_CATEGORIES_CMD), ' '.join(tracer_args))
     self.assertEqual(False, agent.expect_trace())
 
+  def test_construct_trace_from_file_command(self):
+    options, categories = systrace.parse_options(['systrace.py',
+        '--from-file', ATRACE_DATA_RAW_FROM_FILE])
+    agent = atrace_agent.try_create_agent(options, categories)
+    tracer_args = agent._construct_trace_command()
+    self.assertEqual(' '.join(['cat', ATRACE_DATA_RAW_FROM_FILE]),
+            ' '.join(tracer_args))
+    self.assertEqual(True, agent.expect_trace())
+
 class AtraceLegacyAgentUnitTest(unittest.TestCase):
   def test_construct_trace_command(self):
     options, categories = systrace.parse_options(SYSTRACE_CMD)