diff options
| -rw-r--r-- | Lib/subprocess.py | 10 | ||||
| -rw-r--r-- | Lib/test/test_subprocess.py | 47 | ||||
| -rw-r--r-- | Misc/NEWS | 4 | ||||
| -rw-r--r-- | Modules/_posixsubprocess.c | 7 |
4 files changed, 59 insertions, 9 deletions
diff --git a/Lib/subprocess.py b/Lib/subprocess.py index 775db50..57cc1a4 100644 --- a/Lib/subprocess.py +++ b/Lib/subprocess.py @@ -1327,6 +1327,7 @@ class Popen(object): if executable is None: executable = args[0] + orig_executable = executable # For transferring possible exec failure from child to parent. # Data format: "exception name:hex errno:description" @@ -1409,10 +1410,17 @@ class Popen(object): err_msg = err_msg.decode(errors="surrogatepass") if issubclass(child_exception_type, OSError) and hex_errno: errno_num = int(hex_errno, 16) + child_exec_never_called = (err_msg == "noexec") + if child_exec_never_called: + err_msg = "" if errno_num != 0: err_msg = os.strerror(errno_num) if errno_num == errno.ENOENT: - err_msg += ': ' + repr(args[0]) + if child_exec_never_called: + # The error must be from chdir(cwd). + err_msg += ': ' + repr(cwd) + else: + err_msg += ': ' + repr(orig_executable) raise child_exception_type(errno_num, err_msg) raise child_exception_type(err_msg) diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py index 8f5a58c..b260c81 100644 --- a/Lib/test/test_subprocess.py +++ b/Lib/test/test_subprocess.py @@ -1038,24 +1038,30 @@ class _SuppressCoreFiles(object): @unittest.skipIf(mswindows, "POSIX specific tests") class POSIXProcessTestCase(BaseTestCase): - def test_exceptions(self): - nonexistent_dir = "/_this/pa.th/does/not/exist" + def setUp(self): + super().setUp() + self._nonexistent_dir = "/_this/pa.th/does/not/exist" + + def _get_chdir_exception(self): try: - os.chdir(nonexistent_dir) + os.chdir(self._nonexistent_dir) except OSError as e: # This avoids hard coding the errno value or the OS perror() # string and instead capture the exception that we want to see # below for comparison. desired_exception = e - desired_exception.strerror += ': ' + repr(sys.executable) + desired_exception.strerror += ': ' + repr(self._nonexistent_dir) else: self.fail("chdir to nonexistant directory %s succeeded." % - nonexistent_dir) + self._nonexistent_dir) + return desired_exception - # Error in the child re-raised in the parent. + def test_exception_cwd(self): + """Test error in the child raised in the parent for a bad cwd.""" + desired_exception = self._get_chdir_exception() try: p = subprocess.Popen([sys.executable, "-c", ""], - cwd=nonexistent_dir) + cwd=self._nonexistent_dir) except OSError as e: # Test that the child process chdir failure actually makes # it up to the parent process as the correct exception. @@ -1064,6 +1070,33 @@ class POSIXProcessTestCase(BaseTestCase): else: self.fail("Expected OSError: %s" % desired_exception) + def test_exception_bad_executable(self): + """Test error in the child raised in the parent for a bad executable.""" + desired_exception = self._get_chdir_exception() + try: + p = subprocess.Popen([sys.executable, "-c", ""], + executable=self._nonexistent_dir) + except OSError as e: + # Test that the child process exec failure actually makes + # it up to the parent process as the correct exception. + self.assertEqual(desired_exception.errno, e.errno) + self.assertEqual(desired_exception.strerror, e.strerror) + else: + self.fail("Expected OSError: %s" % desired_exception) + + def test_exception_bad_args_0(self): + """Test error in the child raised in the parent for a bad args[0].""" + desired_exception = self._get_chdir_exception() + try: + p = subprocess.Popen([self._nonexistent_dir, "-c", ""]) + except OSError as e: + # Test that the child process exec failure actually makes + # it up to the parent process as the correct exception. + self.assertEqual(desired_exception.errno, e.errno) + self.assertEqual(desired_exception.strerror, e.strerror) + else: + self.fail("Expected OSError: %s" % desired_exception) + def test_restore_signals(self): # Code coverage for both values of restore_signals to make sure it # at least does not blow up. @@ -37,6 +37,10 @@ Core and Builtins Library ------- +- Issue #16114: The subprocess module no longer provides a misleading error + message stating that args[0] did not exist when either the cwd or executable + keyword arguments specified a path that did not exist. + - Issue #16169: Fix ctypes.WinError()'s confusion between errno and winerror. - Issue #16089: Allow ElementTree.TreeBuilder to work again with a non-Element diff --git a/Modules/_posixsubprocess.c b/Modules/_posixsubprocess.c index 8f0fcf2..b7b120b 100644 --- a/Modules/_posixsubprocess.c +++ b/Modules/_posixsubprocess.c @@ -356,7 +356,7 @@ child_exec(char *const exec_array[], PyObject *preexec_fn, PyObject *preexec_fn_args_tuple) { - int i, saved_errno, unused; + int i, saved_errno, unused, reached_preexec = 0; PyObject *result; const char* err_msg = ""; /* Buffer large enough to hold a hex integer. We can't malloc. */ @@ -440,6 +440,7 @@ child_exec(char *const exec_array[], POSIX_CALL(setsid()); #endif + reached_preexec = 1; if (preexec_fn != Py_None && preexec_fn_args_tuple) { /* This is where the user has asked us to deadlock their program. */ result = PyObject_Call(preexec_fn, preexec_fn_args_tuple, NULL); @@ -489,6 +490,10 @@ error: } unused = write(errpipe_write, cur, hex_errno + sizeof(hex_errno) - cur); unused = write(errpipe_write, ":", 1); + if (!reached_preexec) { + /* Indicate to the parent that the error happened before exec(). */ + unused = write(errpipe_write, "noexec", 6); + } /* We can't call strerror(saved_errno). It is not async signal safe. * The parent process will look the error message up. */ } else { |