Merge pull request #6576 from jenshnielsen/subprocess_changes2

tacaswell · web-flow · commit 1c08c1671f60 · 2016-07-12T08:11:51.000-05:00
MNT: Use subprocess32 on python 2.7
diff --git a/lib/matplotlib/compat/subprocess.py b/lib/matplotlib/compat/subprocess.py
@@ -1,10 +1,10 @@
 """
 A replacement wrapper around the subprocess module, with a number of
 work-arounds:
-- Provides the check_output function (which subprocess only provides from Python
-  2.7 onwards).
 - Provides a stub implementation of subprocess members on Google App Engine
   (which are missing in subprocess).
+- Use subprocess32, backport from python 3.2 on Linux/Mac work-around for
+  https://github.com/matplotlib/matplotlib/issues/5314
 
 Instead of importing subprocess, other modules should use this as follows:
 
@@ -15,8 +15,16 @@
 
 from __future__ import absolute_import    # Required to import subprocess
 from __future__ import print_function
-
-import subprocess
+import os
+import sys
+if os.name == 'posix' and sys.version_info[:2] < (3, 2):
+    # work around for https://github.com/matplotlib/matplotlib/issues/5314
+    try:
+        import subprocess32 as subprocess
+    except ImportError:
+        import subprocess
+else:
+    import subprocess
 
 __all__ = ['Popen', 'PIPE', 'STDOUT', 'check_output', 'CalledProcessError']
 
@@ -27,55 +35,17 @@
     PIPE = subprocess.PIPE
     STDOUT = subprocess.STDOUT
     CalledProcessError = subprocess.CalledProcessError
+    check_output = subprocess.check_output
 else:
     # In restricted environments (such as Google App Engine), these are
     # non-existent. Replace them with dummy versions that always raise OSError.
     def Popen(*args, **kwargs):
         raise OSError("subprocess.Popen is not supported")
+
+    def check_output(*args, **kwargs):
+        raise OSError("subprocess.check_output is not supported")
     PIPE = -1
     STDOUT = -2
     # There is no need to catch CalledProcessError. These stubs cannot raise
     # it. None in an except clause will simply not match any exceptions.
     CalledProcessError = None
-
-
-def _check_output(*popenargs, **kwargs):
-    r"""Run command with arguments and return its output as a byte
-    string.
-
-    If the exit code was non-zero it raises a CalledProcessError.  The
-    CalledProcessError object will have the return code in the
-    returncode
-    attribute and output in the output attribute.
-
-    The arguments are the same as for the Popen constructor.  Example::
-
-    >>> check_output(["ls", "-l", "/dev/null"])
-    'crw-rw-rw- 1 root root 1, 3 Oct 18  2007 /dev/null\n'
-
-    The stdout argument is not allowed as it is used internally.
-    To capture standard error in the result, use stderr=STDOUT.::
-
-    >>> check_output(["/bin/sh", "-c",
-    ...               "ls -l non_existent_file ; exit 0"],
-    ...              stderr=STDOUT)
-    'ls: non_existent_file: No such file or directory\n'
-    """
-    if 'stdout' in kwargs:
-        raise ValueError('stdout argument not allowed, it will be overridden.')
-    process = Popen(stdout=PIPE, *popenargs, **kwargs)
-    output, unused_err = process.communicate()
-    retcode = process.poll()
-    if retcode:
-        cmd = kwargs.get("args")
-        if cmd is None:
-            cmd = popenargs[0]
-        raise subprocess.CalledProcessError(retcode, cmd, output=output)
-    return output
-
-
-# python2.7's subprocess provides a check_output method
-if hasattr(subprocess, 'check_output'):
-    check_output = subprocess.check_output
-else:
-    check_output = _check_output
diff --git a/lib/matplotlib/tests/test_coding_standards.py b/lib/matplotlib/tests/test_coding_standards.py
@@ -217,7 +217,6 @@ def test_pep8_conformance_installed_files():
                           'tests/test_subplots.py',
                           'tests/test_tightlayout.py',
                           'tests/test_triangulation.py',
-                          'compat/subprocess.py',
                           'backends/__init__.py',
                           'backends/backend_agg.py',
                           'backends/backend_cairo.py',
diff --git a/setup.py b/setup.py
@@ -70,6 +70,7 @@
     setupext.Six(),
     setupext.Dateutil(),
     setupext.FuncTools32(),
+    setupext.Subprocess32(),
     setupext.Pytz(),
     setupext.Cycler(),
     setupext.Tornado(),
diff --git a/setupext.py b/setupext.py
@@ -1386,8 +1386,8 @@ def check(self):
                 import functools32
             except ImportError:
                 return (
-                    "functools32 was not found. It is required for for"
-                    "python versions prior to 3.2")
+                    "functools32 was not found. It is required for"
+                    "Python versions prior to 3.2")
 
             return "using functools32"
         else:
@@ -1400,6 +1400,30 @@ def get_install_requires(self):
             return []
 
 
+class Subprocess32(SetupPackage):
+    name = "subprocess32"
+
+    def check(self):
+        if sys.version_info[:2] < (3, 2):
+            try:
+                import subprocess32
+            except ImportError:
+                return (
+                    "subprocess32 was not found. It used "
+                    " for Python versions prior to 3.2 to improves"
+                    " functionality on Linux and OSX")
+
+            return "using subprocess32"
+        else:
+            return "Not required"
+
+    def get_install_requires(self):
+        if sys.version_info[:2] < (3, 2) and os.name == 'posix':
+            return ['subprocess32']
+        else:
+            return []
+
+
 class Tornado(OptionalPackage):
     name = "tornado"
 
