1 files changed, 133 insertions, 0 deletions
diff --git a/powerline/lib/shell.py b/powerline/lib/shell.py
new file mode 100644
index 0000000..2082e82
--- /dev/null
+++ b/powerline/lib/shell.py
@@ -0,0 +1,133 @@
+# vim:fileencoding=utf-8:noet
+from __future__ import (unicode_literals, division, absolute_import, print_function)
+
+import sys
+import os
+
+from subprocess import Popen, PIPE
+from functools import partial
+
+from powerline.lib.encoding import get_preferred_input_encoding, get_preferred_output_encoding
+
+
+if sys.platform.startswith('win32'):
+	# Prevent windows from launching consoles when calling commands
+	# http://msdn.microsoft.com/en-us/library/windows/desktop/ms684863(v=vs.85).aspx
+	Popen = partial(Popen, creationflags=0x08000000)
+
+
+def run_cmd(pl, cmd, stdin=None, strip=True):
+	'''Run command and return its stdout, stripped
+
+	If running command fails returns None and logs failure to ``pl`` argument.
+
+	:param PowerlineLogger pl:
+		Logger used to log failures.
+	:param list cmd:
+		Command which will be run.
+	:param str stdin:
+		String passed to command. May be None.
+	:param bool strip:
+		True if the result should be stripped.
+	'''
+	try:
+		p = Popen(cmd, shell=False, stdout=PIPE, stdin=PIPE)
+	except OSError as e:
+		pl.exception('Could not execute command ({0}): {1}', e, cmd)
+		return None
+	else:
+		stdout, err = p.communicate(
+			stdin if stdin is None else stdin.encode(get_preferred_output_encoding()))
+		stdout = stdout.decode(get_preferred_input_encoding())
+	return stdout.strip() if strip else stdout
+
+
+def asrun(pl, ascript):
+	'''Run the given AppleScript and return the standard output and error.'''
+	return run_cmd(pl, ['osascript', '-'], ascript)
+
+
+def readlines(cmd, cwd):
+	'''Run command and read its output, line by line
+
+	:param list cmd:
+		Command which will be run.
+	:param str cwd:
+		Working directory of the command which will be run.
+	'''
+	p = Popen(cmd, shell=False, stdout=PIPE, stderr=PIPE, cwd=cwd)
+	encoding = get_preferred_input_encoding()
+	p.stderr.close()
+	with p.stdout:
+		for line in p.stdout:
+			yield line[:-1].decode(encoding)
+
+
+try:
+	from shutil import which
+except ImportError:
+	# shutil.which was added in python-3.3. Here is what was added:
+	# Lib/shutil.py, commit 5abe28a9c8fe701ba19b1db5190863384e96c798
+	def which(cmd, mode=os.F_OK | os.X_OK, path=None):
+		'''Given a command, mode, and a PATH string, return the path which 
+		conforms to the given mode on the PATH, or None if there is no such 
+		file.
+
+		``mode`` defaults to os.F_OK | os.X_OK. ``path`` defaults to the result 
+		of ``os.environ.get('PATH')``, or can be overridden with a custom search 
+		path.
+		'''
+		# Check that a given file can be accessed with the correct mode.
+		# Additionally check that `file` is not a directory, as on Windows
+		# directories pass the os.access check.
+		def _access_check(fn, mode):
+			return (
+				os.path.exists(fn)
+				and os.access(fn, mode)
+				and not os.path.isdir(fn)
+			)
+
+		# If we’re given a path with a directory part, look it up directly rather
+		# than referring to PATH directories. This includes checking relative to the
+		# current directory, e.g. ./script
+		if os.path.dirname(cmd):
+			if _access_check(cmd, mode):
+				return cmd
+			return None
+
+		if path is None:
+			path = os.environ.get('PATH', os.defpath)
+		if not path:
+			return None
+		path = path.split(os.pathsep)
+
+		if sys.platform == 'win32':
+			# The current directory takes precedence on Windows.
+			if os.curdir not in path:
+				path.insert(0, os.curdir)
+
+			# PATHEXT is necessary to check on Windows.
+			pathext = os.environ.get('PATHEXT', '').split(os.pathsep)
+			# See if the given file matches any of the expected path extensions.
+			# This will allow us to short circuit when given 'python.exe'.
+			# If it does match, only test that one, otherwise we have to try
+			# others.
+			if any(cmd.lower().endswith(ext.lower()) for ext in pathext):
+				files = [cmd]
+			else:
+				files = [cmd + ext for ext in pathext]
+		else:
+			# On other platforms you don’t have things like PATHEXT to tell you
+			# what file suffixes are executable, so just pass on cmd as-is.
+			files = [cmd]
+
+		seen = set()
+		for dir in path:
+			normdir = os.path.normcase(dir)
+			if normdir not in seen:
+				seen.add(normdir)
+				for thefile in files:
+					name = os.path.join(dir, thefile)
+					if _access_check(name, mode):
+						return name
+		return None