[benchmark] BenchmarkDriver can run tests

The `run` method on `BenchmarkDriver` invokes the test harness with specified number of iterations, samples. It supports mesuring memory use and in the verbose mode it also collects individual samples and monitors the system load by counting the number of voluntary and involuntary context switches.

Output is parsed using `LogParser` from `compare_perf_tests.py`. This makes that file a required dependency for the driver, therefore it is also copied to the bin directory during the build.

benchmark/scripts/test_Benchmark_Driver.py

@@ -19,6 +19,7 @@ import unittest
 from imp import load_source
 
 from test_utils import Mock, captured_output
+from compare_perf_tests import PerformanceTestResult
 
 # import Benchmark_Driver  # doesn't work because it misses '.py' extension
 Benchmark_Driver = load_source(
@@ -162,6 +163,8 @@ class TestBenchmarkDriverInitialization(unittest.TestCase):
             self.args, _subprocess=self.subprocess_mock)
         self.subprocess_mock.assert_called_all_expected()
         self.assertEquals(driver.tests, ['Benchmark1', 'Benchmark3'])
+        self.assertEquals(driver.all_tests,
+                          ['Benchmark1', 'Benchmark2', 'Benchmark3'])
 
     def test_filters_benchmarks_by_pattern(self):
         self.args.filters = '-f .+3'.split()
@@ -170,6 +173,58 @@ class TestBenchmarkDriverInitialization(unittest.TestCase):
             self.args, _subprocess=self.subprocess_mock)
         self.subprocess_mock.assert_called_all_expected()
         self.assertEquals(driver.tests, ['Benchmark3'])
+        self.assertEquals(driver.all_tests,
+                          ['Benchmark1', 'Benchmark2', 'Benchmark3'])
+
+
+class LogParserStub(object):
+    results_from_string_called = False
+
+    @staticmethod
+    def results_from_string(log_contents):
+        LogParserStub.results_from_string_called = True
+        r = PerformanceTestResult('3,b1,1,123,123,123,0,123'.split(','))
+        return {'b1': r}
+
+
+class TestBenchmarkDriverRunningTests(unittest.TestCase):
+    def setUp(self):
+        self.args = ArgsStub()
+        self.parser_stub = LogParserStub()
+        self.subprocess_mock = SubprocessMock()
+        self.subprocess_mock.expect(
+            '/benchmarks/Benchmark_O --list --delim=\t'.split(' '),
+            '#\tTest\t[Tags]\n1\tb1\t[tag]\n')
+        self.driver = BenchmarkDriver(
+            self.args, _subprocess=self.subprocess_mock,
+            parser=self.parser_stub)
+
+    def test_run_benchmark_with_multiple_samples(self):
+        self.driver.run('b1')
+        self.subprocess_mock.assert_called_with(
+            ('/benchmarks/Benchmark_O', 'b1'))
+        self.driver.run('b2', num_samples=5)
+        self.subprocess_mock.assert_called_with(
+            ('/benchmarks/Benchmark_O', 'b2', '--num-samples=5'))
+
+    def test_run_benchmark_with_specified_number_of_iterations(self):
+        self.driver.run('b', num_iters=1)
+        self.subprocess_mock.assert_called_with(
+            ('/benchmarks/Benchmark_O', 'b', '--num-iters=1'))
+
+    def test_run_benchmark_in_verbose_mode(self):
+        self.driver.run('b', verbose=True)
+        self.subprocess_mock.assert_called_with(
+            ('/benchmarks/Benchmark_O', 'b', '--verbose'))
+
+    def test_parse_results_from_running_benchmarks(self):
+        self.driver.run('b')
+        self.assertTrue(self.parser_stub.results_from_string_called)
+
+    def test_measure_memory(self):
+        self.driver.run('b', measure_memory=True)
+        self.subprocess_mock.assert_called_with(
+            ('/benchmarks/Benchmark_O', 'b', '--memory'))
 
 
 if __name__ == '__main__':