Recorded merge of revisions 78508-78509 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r78508 | florent.xicluna | 2010-02-27 20:20:50 +0100 (sam, 27 fév 2010) | 2 lines

  Clean test_subprocess: use assertRaises, skipIf, skipUnless helpers and a custom helper assertStderrEqual.
........
  r78509 | florent.xicluna | 2010-02-27 22:15:27 +0100 (sam, 27 fév 2010) | 2 lines

  Fix an oversight in r78508: p.wait() should be compared to 0
........

Lib/test/test_subprocess.py

@@ -21,37 +21,30 @@ if mswindows:
 else:
     SETBINARY = ''
 
-# In a debug build, stuff like "[6580 refs]" is printed to stderr at
-# shutdown time.  That frustrates tests trying to check stderr produced
-# from a spawned Python process.
-def remove_stderr_debug_decorations(stderr):
-    return re.sub("\[\d+ refs\]\r?\n?$", "", stderr.decode()).encode()
-    #return re.sub(r"\[\d+ refs\]\r?\n?$", "", stderr)
+
+try:
+    mkstemp = tempfile.mkstemp
+except AttributeError:
+    # tempfile.mkstemp is not available
+    def mkstemp():
+        """Replacement for mkstemp, calling mktemp."""
+        fname = tempfile.mktemp()
+        return os.open(fname, os.O_RDWR|os.O_CREAT), fname
+
 
 class ProcessTestCase(unittest.TestCase):
     def setUp(self):
         # Try to minimize the number of children we have so this test
         # doesn't crash on some buildbots (Alphas in particular).
-        if hasattr(support, "reap_children"):
         support.reap_children()
 
-    def tearDown(self):
-        # Try to minimize the number of children we have so this test
-        # doesn't crash on some buildbots (Alphas in particular).
-        if hasattr(support, "reap_children"):
-            support.reap_children()
+    def assertStderrEqual(self, stderr, expected, msg=None):
+        # In a debug build, stuff like "[6580 refs]" is printed to stderr at
+        # shutdown time.  That frustrates tests trying to check stderr produced
+        # from a spawned Python process.
+        actual = re.sub("\[\d+ refs\]\r?\n?$", "", stderr.decode()).encode()
+        self.assertEqual(actual, expected, msg)
 
-    def mkstemp(self):
-        """wrapper for mkstemp, calling mktemp if mkstemp is not available"""
-        if hasattr(tempfile, "mkstemp"):
-            return tempfile.mkstemp()
-        else:
-            fname = tempfile.mktemp()
-            return os.open(fname, os.O_RDWR|os.O_CREAT), fname
-
-    #
-    # Generic tests
-    #
     def test_call_seq(self):
         # call() function with sequence argument
         rc = subprocess.call([sys.executable, "-c",
@@ -66,13 +59,10 @@ class ProcessTestCase(unittest.TestCase):
 
     def test_check_call_nonzero(self):
         # check_call() function with non-zero return code
-        try:
+        with self.assertRaises(subprocess.CalledProcessError) as c:
             subprocess.check_call([sys.executable, "-c",
                                    "import sys; sys.exit(47)"])
-        except subprocess.CalledProcessError as e:
-            self.assertEqual(e.returncode, 47)
-        else:
-            self.fail("Expected CalledProcessError")
+        self.assertEqual(c.exception.returncode, 47)
 
     def test_check_output(self):
         # check_output() function with zero return code
@@ -82,13 +72,10 @@ class ProcessTestCase(unittest.TestCase):
 
     def test_check_output_nonzero(self):
         # check_call() function with non-zero return code
-        try:
+        with self.assertRaises(subprocess.CalledProcessError) as c:
             subprocess.check_output(
                     [sys.executable, "-c", "import sys; sys.exit(5)"])
-        except subprocess.CalledProcessError as e:
-            self.assertEqual(e.returncode, 5)
-        else:
-            self.fail("Expected CalledProcessError")
+        self.assertEqual(c.exception.returncode, 5)
 
     def test_check_output_stderr(self):
         # check_output() function stderr redirected to stdout
@@ -99,14 +86,12 @@ class ProcessTestCase(unittest.TestCase):
 
     def test_check_output_stdout_arg(self):
         # check_output() function stderr redirected to stdout
-        try:
+        with self.assertRaises(ValueError) as c:
             output = subprocess.check_output(
                     [sys.executable, "-c", "print('will not be run')"],
                     stdout=sys.stdout)
-        except ValueError as e:
-            self.assertIn('stdout', e.args[0])
-        else:
             self.fail("Expected ValueError when stdout arg supplied.")
+        self.assertIn('stdout', c.exception.args[0])
 
     def test_call_kwargs(self):
         # call() function with keyword args
@@ -227,8 +212,7 @@ class ProcessTestCase(unittest.TestCase):
         p = subprocess.Popen([sys.executable, "-c",
                           'import sys; sys.stderr.write("strawberry")'],
                          stderr=subprocess.PIPE)
-        self.assertEqual(remove_stderr_debug_decorations(p.stderr.read()),
-                         b"strawberry")
+        self.assertStderrEqual(p.stderr.read(), b"strawberry")
 
     def test_stderr_filedes(self):
         # stderr is set to open file descriptor
@@ -239,8 +223,7 @@ class ProcessTestCase(unittest.TestCase):
                          stderr=d)
         p.wait()
         os.lseek(d, 0, 0)
-        self.assertEqual(remove_stderr_debug_decorations(os.read(d, 1024)),
-                         b"strawberry")
+        self.assertStderrEqual(os.read(d, 1024), b"strawberry")
 
     def test_stderr_fileobj(self):
         # stderr is set to open file object
@@ -250,8 +233,7 @@ class ProcessTestCase(unittest.TestCase):
                          stderr=tf)
         p.wait()
         tf.seek(0)
-        self.assertEqual(remove_stderr_debug_decorations(tf.read()),
-                         b"strawberry")
+        self.assertStderrEqual(tf.read(), b"strawberry")
 
     def test_stdout_stderr_pipe(self):
         # capture stdout and stderr to the same pipe
@@ -262,9 +244,7 @@ class ProcessTestCase(unittest.TestCase):
                               'sys.stderr.write("orange")'],
                              stdout=subprocess.PIPE,
                              stderr=subprocess.STDOUT)
-        output = p.stdout.read()
-        stripped = remove_stderr_debug_decorations(output)
-        self.assertEqual(stripped, b"appleorange")
+        self.assertStderrEqual(p.stdout.read(), b"appleorange")
 
     def test_stdout_stderr_file(self):
         # capture stdout and stderr to the same open file
@@ -278,15 +258,13 @@ class ProcessTestCase(unittest.TestCase):
                              stderr=tf)
         p.wait()
         tf.seek(0)
-        output = tf.read()
-        stripped = remove_stderr_debug_decorations(output)
-        self.assertEqual(stripped, b"appleorange")
+        self.assertStderrEqual(tf.read(), b"appleorange")
 
     def test_stdout_filedes_of_stdout(self):
         # stdout is set to 1 (#1531862).
         cmd = r"import sys, os; sys.exit(os.write(sys.stdout.fileno(), b'.\n'))"
         rc = subprocess.call([sys.executable, "-c", cmd], stdout=1)
-        self.assertEquals(rc, 2)
+        self.assertEqual(rc, 2)
 
     def test_cwd(self):
         tmpdir = tempfile.gettempdir()
@@ -337,9 +315,7 @@ class ProcessTestCase(unittest.TestCase):
                              stderr=subprocess.PIPE)
         (stdout, stderr) = p.communicate()
         self.assertEqual(stdout, None)
-        # When running with a pydebug build, the # of references is outputted
-        # to stderr, so just check if stderr at least started with "pinapple"
-        self.assertEqual(remove_stderr_debug_decorations(stderr), b"pineapple")
+        self.assertStderrEqual(stderr, b"pineapple")
 
     def test_communicate(self):
         p = subprocess.Popen([sys.executable, "-c",
@@ -351,17 +327,17 @@ class ProcessTestCase(unittest.TestCase):
                              stderr=subprocess.PIPE)
         (stdout, stderr) = p.communicate(b"banana")
         self.assertEqual(stdout, b"banana")
-        self.assertEqual(remove_stderr_debug_decorations(stderr),
-                         b"pineapple")
+        self.assertStderrEqual(stderr, b"pineapple")
 
     # This test is Linux specific for simplicity to at least have
     # some coverage.  It is not a platform specific bug.
-    if os.path.isdir('/proc/%d/fd' % os.getpid()):
+    @unittest.skipUnless(os.path.isdir('/proc/%d/fd' % os.getpid()),
+                         "Linux specific")
     # Test for the fd leak reported in http://bugs.python.org/issue2791.
     def test_communicate_pipe_fd_leak(self):
         fd_directory = '/proc/%d/fd' % os.getpid()
         num_fds_before_popen = len(os.listdir(fd_directory))
-            p = subprocess.Popen([sys.executable, '-c', 'print()'],
+        p = subprocess.Popen([sys.executable, "-c", "print()"],
                              stdout=subprocess.PIPE)
         p.communicate()
         num_fds_after_communicate = len(os.listdir(fd_directory))
@@ -412,7 +388,7 @@ class ProcessTestCase(unittest.TestCase):
         p.stdin.write(b"banana")
         (stdout, stderr) = p.communicate(b"split")
         self.assertEqual(stdout, b"bananasplit")
-        self.assertEqual(remove_stderr_debug_decorations(stderr), b"")
+        self.assertStderrEqual(stderr, b"")
 
     def test_universal_newlines(self):
         p = subprocess.Popen([sys.executable, "-c",
@@ -503,7 +479,7 @@ class ProcessTestCase(unittest.TestCase):
         # but, based on system scheduling we can't control, it's possible
         # poll() never returned None.  It "should be" very rare that it
         # didn't go around at least twice.
-        self.assertTrue(count >= 2)
+        self.assertGreaterEqual(count, 2)
         # Subsequent invocations should just return the returncode
         self.assertEqual(p.poll(), 0)
 
@@ -519,12 +495,8 @@ class ProcessTestCase(unittest.TestCase):
     def test_invalid_bufsize(self):
         # an invalid type of the bufsize argument should raise
         # TypeError.
-        try:
+        with self.assertRaises(TypeError):
             subprocess.Popen([sys.executable, "-c", "pass"], "orange")
-        except TypeError:
-            pass
-        else:
-            self.fail("Expected TypeError")
 
     def test_bufsize_is_none(self):
         # bufsize=None should be the same as bufsize=0.
@@ -541,61 +513,60 @@ class ProcessTestCase(unittest.TestCase):
         # value for that limit, but Windows has 2048, so we loop
         # 1024 times (each call leaked two fds).
         for i in range(1024):
-            try:
+            # Windows raises IOError.  Others raise OSError.
+            with self.assertRaises(EnvironmentError) as c:
                 subprocess.Popen(['nonexisting_i_hope'],
                                  stdout=subprocess.PIPE,
                                  stderr=subprocess.PIPE)
-            # Windows raises IOError
-            except (IOError, OSError) as err:
-                if err.errno != 2:  # ignore "no such file"
-                    raise
-
-    #
-    # POSIX tests
-    #
-    if not mswindows:
-        def test_exceptions(self):
-            # caught & re-raised exceptions
-            try:
-                p = subprocess.Popen([sys.executable, "-c", ""],
-                                     cwd="/this/path/does/not/exist")
-            except OSError as e:
-                # The attribute child_traceback should contain "os.chdir"
-                # somewhere.
-                self.assertNotEqual(e.child_traceback.find("os.chdir"), -1)
-            else:
-                self.fail("Expected OSError")
+            if c.exception.errno != 2:  # ignore "no such file"
+                raise c.exception
 
-        def _suppress_core_files(self):
-            """Try to prevent core files from being created.
-            Returns previous ulimit if successful, else None.
-            """
+
+# context manager
+class _SuppressCoreFiles(object):
+    """Try to prevent core files from being created."""
+    old_limit = None
+
+    def __enter__(self):
+        """Try to save previous ulimit, then set it to (0, 0)."""
         try:
             import resource
-                old_limit = resource.getrlimit(resource.RLIMIT_CORE)
-                resource.setrlimit(resource.RLIMIT_CORE, (0,0))
-                return old_limit
+            self.old_limit = resource.getrlimit(resource.RLIMIT_CORE)
+            resource.setrlimit(resource.RLIMIT_CORE, (0, 0))
         except (ImportError, ValueError, resource.error):
-                return None
+            pass
 
-        def _unsuppress_core_files(self, old_limit):
+    def __exit__(self, *args):
         """Return core file behavior to default."""
-            if old_limit is None:
+        if self.old_limit is None:
             return
         try:
             import resource
-                resource.setrlimit(resource.RLIMIT_CORE, old_limit)
+            resource.setrlimit(resource.RLIMIT_CORE, self.old_limit)
         except (ImportError, ValueError, resource.error):
-                return
+            pass
+
+
+@unittest.skipIf(sys.platform == "win32", "POSIX specific tests")
+class POSIXProcessTestCase(unittest.TestCase):
+    def setUp(self):
+        # Try to minimize the number of children we have so this test
+        # doesn't crash on some buildbots (Alphas in particular).
+        support.reap_children()
+
+    def test_exceptions(self):
+        # caught & re-raised exceptions
+        with self.assertRaises(OSError) as c:
+            p = subprocess.Popen([sys.executable, "-c", ""],
+                                 cwd="/this/path/does/not/exist")
+        # The attribute child_traceback should contain "os.chdir" somewhere.
+        self.assertIn("os.chdir", c.exception.child_traceback)
 
     def test_run_abort(self):
         # returncode handles signal termination
-            old_limit = self._suppress_core_files()
-            try:
-                p = subprocess.Popen([sys.executable,
-                                      "-c", "import os; os.abort()"])
-            finally:
-                self._unsuppress_core_files(old_limit)
+        with _SuppressCoreFiles():
+            p = subprocess.Popen([sys.executable, "-c",
+                                  'import os; os.abort()'])
             p.wait()
         self.assertEqual(-p.returncode, signal.SIGABRT)
 
@@ -605,13 +576,12 @@ class ProcessTestCase(unittest.TestCase):
                               'import sys,os;'
                               'sys.stdout.write(os.getenv("FRUIT"))'],
                              stdout=subprocess.PIPE,
-                                 preexec_fn=lambda: os.putenv("FRUIT",
-                                                              "apple"))
+                             preexec_fn=lambda: os.putenv("FRUIT", "apple"))
         self.assertEqual(p.stdout.read(), b"apple")
 
     def test_args_string(self):
         # args is a string
-            fd, fname = self.mkstemp()
+        fd, fname = mkstemp()
         # reopen in text mode
         with open(fd, "w") as fobj:
             fobj.write("#!/bin/sh\n")
@@ -626,12 +596,12 @@ class ProcessTestCase(unittest.TestCase):
     def test_invalid_args(self):
         # invalid arguments should raise ValueError
         self.assertRaises(ValueError, subprocess.call,
-                              [sys.executable,
-                               "-c", "import sys; sys.exit(47)"],
+                          [sys.executable, "-c",
+                           "import sys; sys.exit(47)"],
                           startupinfo=47)
         self.assertRaises(ValueError, subprocess.call,
-                              [sys.executable,
-                               "-c", "import sys; sys.exit(47)"],
+                          [sys.executable, "-c",
+                           "import sys; sys.exit(47)"],
                           creationflags=47)
 
     def test_shell_sequence(self):
@@ -654,7 +624,7 @@ class ProcessTestCase(unittest.TestCase):
 
     def test_call_string(self):
         # call() function with string argument on UNIX
-            fd, fname = self.mkstemp()
+        fd, fname = mkstemp()
         # reopen in text mode
         with open(fd, "w") as fobj:
             fobj.write("#!/bin/sh\n")
@@ -665,34 +635,38 @@ class ProcessTestCase(unittest.TestCase):
         os.remove(fname)
         self.assertEqual(rc, 47)
 
-        def DISABLED_test_send_signal(self):
-            p = subprocess.Popen([sys.executable,
-                              "-c", "input()"])
+    @unittest.skip("See issue #2777")
+    def test_send_signal(self):
+        p = subprocess.Popen([sys.executable, "-c", "input()"])
 
-            self.assertTrue(p.poll() is None, p.poll())
+        self.assertIs(p.poll(), None)
         p.send_signal(signal.SIGINT)
-            self.assertNotEqual(p.wait(), 0)
+        self.assertIsNot(p.wait(), None)
 
-        def DISABLED_test_kill(self):
-            p = subprocess.Popen([sys.executable,
-                            "-c", "input()"])
+    @unittest.skip("See issue #2777")
+    def test_kill(self):
+        p = subprocess.Popen([sys.executable, "-c", "input()"])
 
-            self.assertTrue(p.poll() is None, p.poll())
+        self.assertIs(p.poll(), None)
         p.kill()
         self.assertEqual(p.wait(), -signal.SIGKILL)
 
-        def DISABLED_test_terminate(self):
-            p = subprocess.Popen([sys.executable,
-                            "-c", "input()"])
+    @unittest.skip("See issue #2777")
+    def test_terminate(self):
+        p = subprocess.Popen([sys.executable, "-c", "input()"])
 
-            self.assertTrue(p.poll() is None, p.poll())
+        self.assertIs(p.poll(), None)
         p.terminate()
         self.assertEqual(p.wait(), -signal.SIGTERM)
 
-    #
-    # Windows tests
-    #
-    if mswindows:
+
+@unittest.skipUnless(sys.platform == "win32", "Windows specific tests")
+class Win32ProcessTestCase(unittest.TestCase):
+    def setUp(self):
+        # Try to minimize the number of children we have so this test
+        # doesn't crash on some buildbots (Alphas in particular).
+        support.reap_children()
+
     def test_startupinfo(self):
         # startupinfo argument
         # We uses hardcoded constants, because we do not want to
@@ -719,12 +693,12 @@ class ProcessTestCase(unittest.TestCase):
     def test_invalid_args(self):
         # invalid arguments should raise ValueError
         self.assertRaises(ValueError, subprocess.call,
-                              [sys.executable,
-                               "-c", "import sys; sys.exit(47)"],
+                          [sys.executable, "-c",
+                           "import sys; sys.exit(47)"],
                           preexec_fn=lambda: 1)
         self.assertRaises(ValueError, subprocess.call,
-                              [sys.executable,
-                               "-c", "import sys; sys.exit(47)"],
+                          [sys.executable, "-c",
+                           "import sys; sys.exit(47)"],
                           stdout=subprocess.PIPE,
                           close_fds=True)
 
@@ -742,7 +716,7 @@ class ProcessTestCase(unittest.TestCase):
         p = subprocess.Popen(["set"], shell=1,
                              stdout=subprocess.PIPE,
                              env=newenv)
-            self.assertNotEqual(p.stdout.read().find(b"physalis"), -1)
+        self.assertIn(b"physalis", p.stdout.read())
 
     def test_shell_string(self):
         # Run command through the shell (string)
@@ -751,7 +725,7 @@ class ProcessTestCase(unittest.TestCase):
         p = subprocess.Popen("set", shell=1,
                              stdout=subprocess.PIPE,
                              env=newenv)
-            self.assertNotEqual(p.stdout.read().find(b"physalis"), -1)
+        self.assertIn(b"physalis", p.stdout.read())
 
     def test_call_string(self):
         # call() function with string argument on Windows
@@ -759,41 +733,41 @@ class ProcessTestCase(unittest.TestCase):
                              ' -c "import sys; sys.exit(47)"')
         self.assertEqual(rc, 47)
 
-        def DISABLED_test_send_signal(self):
-            p = subprocess.Popen([sys.executable,
-                              "-c", "input()"])
+    @unittest.skip("See issue #2777")
+    def test_send_signal(self):
+        p = subprocess.Popen([sys.executable, "-c", "input()"])
 
-            self.assertTrue(p.poll() is None, p.poll())
+        self.assertIs(p.poll(), None)
         p.send_signal(signal.SIGTERM)
         self.assertNotEqual(p.wait(), 0)
 
-        def DISABLED_test_kill(self):
-            p = subprocess.Popen([sys.executable,
-                            "-c", "input()"])
+    @unittest.skip("See issue #2777")
+    def test_kill(self):
+        p = subprocess.Popen([sys.executable, "-c", "input()"])
 
-            self.assertTrue(p.poll() is None, p.poll())
+        self.assertIs(p.poll(), None)
         p.kill()
         self.assertNotEqual(p.wait(), 0)
 
-        def DISABLED_test_terminate(self):
-            p = subprocess.Popen([sys.executable,
-                            "-c", "input()"])
+    @unittest.skip("See issue #2777")
+    def test_terminate(self):
+        p = subprocess.Popen([sys.executable, "-c", "input()"])
 
-            self.assertTrue(p.poll() is None, p.poll())
+        self.assertIs(p.poll(), None)
         p.terminate()
         self.assertNotEqual(p.wait(), 0)
 
-class CommandTests(unittest.TestCase):
+
 # The module says:
 #   "NB This only works (and is only relevant) for UNIX."
 #
 # Actually, getoutput should work on any platform with an os.popen, but
 # I'll take the comment as given, and skip this suite.
-    if os.name == 'posix':
-
+@unittest.skipUnless(os.name != 'posix', "only relevant for UNIX")
+class CommandTests(unittest.TestCase):
     def test_getoutput(self):
-            self.assertEquals(subprocess.getoutput('echo xyzzy'), 'xyzzy')
-            self.assertEquals(subprocess.getstatusoutput('echo xyzzy'),
+        self.assertEqual(subprocess.getoutput('echo xyzzy'), 'xyzzy')
+        self.assertEqual(subprocess.getstatusoutput('echo xyzzy'),
                          (0, 'xyzzy'))
 
         # we use mkdtemp in the next line to create an empty directory
@@ -805,16 +779,15 @@ class CommandTests(unittest.TestCase):
             name = os.path.join(dir, "foo")
 
             status, output = subprocess.getstatusoutput('cat ' + name)
-                self.assertNotEquals(status, 0)
+            self.assertNotEqual(status, 0)
         finally:
             if dir is not None:
                 os.rmdir(dir)
 
 
-unit_tests = [ProcessTestCase, CommandTests]
-
-if getattr(subprocess, '_has_poll', False):
-    class ProcessTestCaseNoPoll(ProcessTestCase):
+@unittest.skipUnless(getattr(subprocess, '_has_poll', False),
+                     "poll system call not supported")
+class ProcessTestCaseNoPoll(ProcessTestCase):
     def setUp(self):
         subprocess._has_poll = False
         ProcessTestCase.setUp(self)
@@ -823,10 +796,14 @@ if getattr(subprocess, '_has_poll', False):
         subprocess._has_poll = True
         ProcessTestCase.tearDown(self)
 
-    unit_tests.append(ProcessTestCaseNoPoll)
-
 
 def test_main():
+    unit_tests = (ProcessTestCase,
+                  POSIXProcessTestCase,
+                  Win32ProcessTestCase,
+                  CommandTests,
+                  ProcessTestCaseNoPoll)
+
     support.run_unittest(*unit_tests)
     support.reap_children()