bpo-30764: test_subprocess uses SuppressCrashReport (#2405) (#2411)

vstinner · web-flow · commit 849b062a82ca · 2017-06-26T18:05:21.000+02:00
bpo-30764, bpo-29335: test_child_terminated_in_stopped_state() of test_subprocess now uses support.SuppressCrashReport() to prevent the creation of a core dump on FreeBSD. (cherry picked from commit cdee3f1)
diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py
@@ -25,6 +25,8 @@
     import ctypes
 except ImportError:
     ctypes = None
+else:
+    import ctypes.util
 
 try:
     import threading
@@ -2505,43 +2507,40 @@ def test_communicate_BrokenPipeError_stdin_close_with_timeout(self):
             proc.communicate(timeout=999)
             mock_proc_stdin.close.assert_called_once_with()
 
-    _libc_file_extensions = {
-      'Linux': 'so.6',
-      'Darwin': 'dylib',
-    }
-    @unittest.skipIf(not ctypes, 'ctypes module required.')
-    @unittest.skipIf(platform.uname()[0] not in _libc_file_extensions,
-                     'Test requires a libc this code can load with ctypes.')
-    @unittest.skipIf(not sys.executable, 'Test requires sys.executable.')
+    @unittest.skipIf(not ctypes, 'ctypes module required')
+    @unittest.skipIf(not sys.executable, 'Test requires sys.executable')
     def test_child_terminated_in_stopped_state(self):
         """Test wait() behavior when waitpid returns WIFSTOPPED; issue29335."""
         PTRACE_TRACEME = 0  # From glibc and MacOS (PT_TRACE_ME).
-        libc_name = 'libc.' + self._libc_file_extensions[platform.uname()[0]]
+        libc_name = ctypes.util.find_library('c')
         libc = ctypes.CDLL(libc_name)
         if not hasattr(libc, 'ptrace'):
-            raise unittest.SkipTest('ptrace() required.')
-        test_ptrace = subprocess.Popen(
-            [sys.executable, '-c', """if True:
-             import ctypes
-             libc = ctypes.CDLL({libc_name!r})
-             libc.ptrace({PTRACE_TRACEME}, 0, 0)
-             """.format(libc_name=libc_name, PTRACE_TRACEME=PTRACE_TRACEME)
-            ])
-        if test_ptrace.wait() != 0:
-            raise unittest.SkipTest('ptrace() failed - unable to test.')
-        child = subprocess.Popen(
-            [sys.executable, '-c', """if True:
+            raise unittest.SkipTest('ptrace() required')
+
+        code = textwrap.dedent("""
              import ctypes
+             import faulthandler
+             from test.support import SuppressCrashReport
+
              libc = ctypes.CDLL({libc_name!r})
              libc.ptrace({PTRACE_TRACEME}, 0, 0)
-             libc.printf(ctypes.c_char_p(0xdeadbeef))  # Crash the process.
-             """.format(libc_name=libc_name, PTRACE_TRACEME=PTRACE_TRACEME)
-            ])
+        """.format(libc_name=libc_name, PTRACE_TRACEME=PTRACE_TRACEME))
+
+        child = subprocess.Popen([sys.executable, '-c', code])
+        if child.wait() != 0:
+            raise unittest.SkipTest('ptrace() failed - unable to test')
+
+        code += textwrap.dedent("""
+             with SuppressCrashReport():
+                # Crash the process
+                faulthandler._sigsegv()
+        """)
+        child = subprocess.Popen([sys.executable, '-c', code])
         try:
             returncode = child.wait()
-        except Exception as e:
+        except:
             child.kill()  # Clean up the hung stopped process.
-            raise e
+            raise
         self.assertNotEqual(0, returncode)
         self.assertLess(returncode, 0)  # signal death, likely SIGSEGV.
 
