[Python-checkins] bpo-40094: Enhance fork and wait tests (GH-19259)

Tue Mar 31 15:46:51 EDT 2020

https://github.com/python/cpython/commit/27c6231f5827fe17c6cb6f097391931f30b511ec
commit: 27c6231f5827fe17c6cb6f097391931f30b511ec
branch: master
author: Victor Stinner <vstinner at python.org>
committer: GitHub <noreply at github.com>
date: 2020年03月31日T21:46:40+02:00
summary:
bpo-40094: Enhance fork and wait tests (GH-19259)
* test_fork1: remove duplicated wait_impl() method: reuse
 fork_wait.py implementation instead.
* Use exit code different than 0 to ensure that we executed the
 expected code path.
files:
M Lib/test/fork_wait.py
M Lib/test/test_fork1.py
M Lib/test/test_wait3.py
M Lib/test/test_wait4.py

diff --git a/Lib/test/fork_wait.py b/Lib/test/fork_wait.py
index 8c177556a4e33..249b5e9607329 100644
--- a/Lib/test/fork_wait.py
+++ b/Lib/test/fork_wait.py
@@ -43,8 +43,8 @@ def f(self, id):
 except OSError:
 pass
 
- def wait_impl(self, cpid):
- support.wait_process(cpid, exitcode=0)
+ def wait_impl(self, cpid, *, exitcode):
+ support.wait_process(cpid, exitcode=exitcode)
 
 def test_wait(self):
 for i in range(NUM_THREADS):
@@ -79,4 +79,4 @@ def test_wait(self):
 os._exit(n)
 else:
 # Parent
- self.wait_impl(cpid)
+ self.wait_impl(cpid, exitcode=0)
diff --git a/Lib/test/test_fork1.py b/Lib/test/test_fork1.py
index ce0a05a541a73..a2f7cfee9cf69 100644
--- a/Lib/test/test_fork1.py
+++ b/Lib/test/test_fork1.py
@@ -17,19 +17,6 @@
 support.get_attribute(os, 'fork')
 
 class ForkTest(ForkWait):
- def wait_impl(self, cpid):
- deadline = time.monotonic() + support.SHORT_TIMEOUT
- while time.monotonic() <= deadline:
- # waitpid() shouldn't hang, but some of the buildbots seem to hang
- # in the forking tests. This is an attempt to fix the problem.
- spid, status = os.waitpid(cpid, os.WNOHANG)
- if spid == cpid:
- break
- time.sleep(0.1)
-
- self.assertEqual(spid, cpid)
- self.assertEqual(status, 0, "cause = %d, exit = %d" % (status&0xff, status>>8))
-
 def test_threaded_import_lock_fork(self):
 """Check fork() in main thread works while a subthread is doing an import"""
 import_started = threading.Event()
@@ -46,6 +33,7 @@ def importer():
 t = threading.Thread(target=importer)
 t.start()
 import_started.wait()
+ exitcode = 42
 pid = os.fork()
 try:
 # PyOS_BeforeFork should have waited for the import to complete
@@ -54,7 +42,7 @@ def importer():
 if not pid:
 m = __import__(fake_module_name)
 if m == complete_module:
- os._exit(0)
+ os._exit(exitcode)
 else:
 if support.verbose > 1:
 print("Child encountered partial module")
@@ -64,7 +52,7 @@ def importer():
 # Exitcode 1 means the child got a partial module (bad.) No
 # exitcode (but a hang, which manifests as 'got pid 0')
 # means the child deadlocked (also bad.)
- self.wait_impl(pid)
+ self.wait_impl(pid, exitcode=exitcode)
 finally:
 try:
 os.kill(pid, signal.SIGKILL)
@@ -74,6 +62,7 @@ def importer():
 
 def test_nested_import_lock_fork(self):
 """Check fork() in main thread works while the main thread is doing an import"""
+ exitcode = 42
 # Issue 9573: this used to trigger RuntimeError in the child process
 def fork_with_import_lock(level):
 release = 0
@@ -95,8 +84,8 @@ def fork_with_import_lock(level):
 os._exit(1)
 raise
 if in_child:
- os._exit(0)
- self.wait_impl(pid)
+ os._exit(exitcode)
+ self.wait_impl(pid, exitcode=exitcode)
 
 # Check this works with various levels of nested
 # import in the main thread
diff --git a/Lib/test/test_wait3.py b/Lib/test/test_wait3.py
index 2dc63aaffa346..6e06049fbdd69 100644
--- a/Lib/test/test_wait3.py
+++ b/Lib/test/test_wait3.py
@@ -16,7 +16,7 @@
 raise unittest.SkipTest("os.wait3 not defined")
 
 class Wait3Test(ForkWait):
- def wait_impl(self, cpid):
+ def wait_impl(self, cpid, *, exitcode):
 # This many iterations can be required, since some previously run
 # tests (e.g. test_ctypes) could have spawned a lot of children
 # very quickly.
@@ -30,7 +30,8 @@ def wait_impl(self, cpid):
 time.sleep(0.1)
 
 self.assertEqual(spid, cpid)
- self.assertEqual(status, 0, "cause = %d, exit = %d" % (status&0xff, status>>8))
+ self.assertEqual(status, exitcode << 8,
+ "cause = %d, exit = %d" % (status&0xff, status>>8))
 self.assertTrue(rusage)
 
 def test_wait3_rusage_initialized(self):
diff --git a/Lib/test/test_wait4.py b/Lib/test/test_wait4.py
index a18607252aa96..6c7ebcb3dd29c 100644
--- a/Lib/test/test_wait4.py
+++ b/Lib/test/test_wait4.py
@@ -14,7 +14,7 @@
 
 
 class Wait4Test(ForkWait):
- def wait_impl(self, cpid):
+ def wait_impl(self, cpid, *, exitcode):
 option = os.WNOHANG
 if sys.platform.startswith('aix'):
 # Issue #11185: wait4 is broken on AIX and will always return 0
@@ -29,7 +29,8 @@ def wait_impl(self, cpid):
 break
 time.sleep(0.1)
 self.assertEqual(spid, cpid)
- self.assertEqual(status, 0, "cause = %d, exit = %d" % (status&0xff, status>>8))
+ self.assertEqual(status, exitcode << 8,
+ "cause = %d, exit = %d" % (status&0xff, status>>8))
 self.assertTrue(rusage)
 
 def tearDownModule():
