Googletest export

gtest: Add a flag to only set up/tear down test environments once when repeating

Currently when running a test multiple times using `--gtest_repeat` the global
test environment(s) are set up and torn down for each iteration of the test.
When checking for flakes in tests that have expensive dependencies that are set
up in the test environment (subprocesses, external dependencies, etc) this can
become expensive.

To support finding flakes in tests that fit into this category, where the setup
phase is expensive but each test case is fast, allow callers to specify via
`--gtest_recreate_environments_when_repeating=false` that the test environments
should only be set up once, for the first iteration, and only torn down once, on
the last iteration. This makes running a test with `--gtest_repeat=1000` a much
faster and more pleasant experience.

PiperOrigin-RevId: 382748942

1 files changed, 58 insertions, 2 deletions

diff --git a/googletest/test/googletest-global-environment-unittest.py b/googletest/test/googletest-global-environment-unittest.py
index 32ba628..f347559 100644
--- a/googletest/test/googletest-global-environment-unittest.py
+++ b/googletest/test/googletest-global-environment-unittest.py
@@ -35,16 +35,17 @@ This script tests such functionality by invoking
 googletest-global-environment-unittest_ (a program written with Google Test).
 """
 
+import re
 import gtest_test_utils
 
 
-def RunAndReturnOutput():
+def RunAndReturnOutput(args=None):
   """Runs the test program and returns its output."""
 
   return gtest_test_utils.Subprocess([
       gtest_test_utils.GetTestExecutablePath(
           'googletest-global-environment-unittest_')
-  ]).output
+  ] + (args or [])).output
 
 
 class GTestGlobalEnvironmentUnitTest(gtest_test_utils.TestCase):
@@ -67,6 +68,61 @@ class GTestGlobalEnvironmentUnitTest(gtest_test_utils.TestCase):
     # The test case shouldn't have been run.
     self.assertNotIn('Unexpected call', txt)
 
+  def testEnvironmentSetUpAndTornDownForEachRepeat(self):
+    """Tests the behavior of test environments and gtest_repeat."""
+
+    txt = RunAndReturnOutput(['--gtest_repeat=2'])
+
+    # By default, with gtest_repeat=2, the global test environment should be set
+    # up and torn down for each iteration.
+    expected_pattern = ('(.|\n)*'
+                        r'Repeating all tests \(iteration 1\)'
+                        '(.|\n)*'
+                        'Global test environment set-up.'
+                        '(.|\n)*'
+                        'SomeTest.DoesFoo'
+                        '(.|\n)*'
+                        'Global test environment tear-down'
+                        '(.|\n)*'
+                        r'Repeating all tests \(iteration 2\)'
+                        '(.|\n)*'
+                        'Global test environment set-up.'
+                        '(.|\n)*'
+                        'SomeTest.DoesFoo'
+                        '(.|\n)*'
+                        'Global test environment tear-down'
+                        '(.|\n)*')
+    self.assertRegex(txt, expected_pattern)
+
+  def testEnvironmentSetUpAndTornDownOnce(self):
+    """Tests environment and --gtest_recreate_environments_when_repeating."""
+
+    txt = RunAndReturnOutput([
+        '--gtest_repeat=2', '--gtest_recreate_environments_when_repeating=false'
+    ])
+
+    # When --gtest_recreate_environments_when_repeating is false, the test
+    # environment should only be set up and torn down once, at the start and
+    # end of the test respectively.
+    expected_pattern = ('(.|\n)*'
+                        r'Repeating all tests \(iteration 1\)'
+                        '(.|\n)*'
+                        'Global test environment set-up.'
+                        '(.|\n)*'
+                        'SomeTest.DoesFoo'
+                        '(.|\n)*'
+                        r'Repeating all tests \(iteration 2\)'
+                        '(.|\n)*'
+                        'SomeTest.DoesFoo'
+                        '(.|\n)*'
+                        'Global test environment tear-down'
+                        '(.|\n)*')
+    self.assertRegex(txt, expected_pattern)
+
+    self.assertEqual(len(re.findall('Global test environment set-up', txt)), 1)
+    self.assertEqual(
+        len(re.findall('Global test environment tear-down', txt)), 1)
+
 
 if __name__ == '__main__':
   gtest_test_utils.Main()