Don't use subprocess.check_output()

It isn't in Python 2.6

ckan/new_tests/test_coding_standards.py

@@ -9,6 +9,43 @@
 import subprocess
 
 
+# We implement our own check_output() function because
+# subprocess.check_output() isn't in Python 2.6.
+# This code is copy-pasted from Python 2.7:
+# http://hg.python.org/cpython/file/d37f963394aa/Lib/subprocess.py#l544
+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 = subprocess.Popen(stdout=subprocess.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
+
+
 def test_building_the_docs():
     '''There should be no warnings or errors when building the Sphinx docs.
 
@@ -20,7 +57,7 @@ def test_building_the_docs():
 
     '''
     try:
-        output = subprocess.check_output(
+        output = check_output(
             ['python', 'setup.py', 'build_sphinx', '--all-files', '--fresh-env'],
             stderr=subprocess.STDOUT)
     except subprocess.CalledProcessError as err:

doc/conf.py

@@ -115,6 +115,43 @@
 release = ckan.__version__
 
 
+# We implement our own check_output() function because
+# subprocess.check_output() isn't in Python 2.6.
+# This code is copy-pasted from Python 2.7:
+# http://hg.python.org/cpython/file/d37f963394aa/Lib/subprocess.py#l544
+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 = subprocess.Popen(stdout=subprocess.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
+
+
 def latest_release_tag():
     '''Return the name of the git tag for the latest stable release.
 
@@ -123,7 +160,7 @@ def latest_release_tag():
     This requires git to be installed.
 
     '''
-    git_tags = subprocess.check_output(['git', 'tag', '-l']).split()
+    git_tags = check_output(['git', 'tag', '-l']).split()
 
     # FIXME: We could do more careful pattern matching against ckan-X.Y.Z here.
     release_tags = [tag for tag in git_tags if tag.startswith('ckan-')]