--- /dev/null
+#!/usr/bin/env python
+
+"""Misc. useful functionality used by the rest of this package.
+
+This module provides common functionality used by the other modules in
+this package.
+
+"""
+
+import sys
+import os
+import subprocess
+
+
+# Whether or not to show debug messages
+DEBUG = False
+
+def notify(msg, *args):
+ """Print a message to stderr."""
+ print >> sys.stderr, msg % args
+
+def debug (msg, *args):
+ """Print a debug message to stderr when DEBUG is enabled."""
+ if DEBUG:
+ print >> sys.stderr, msg % args
+
+def error (msg, *args):
+ """Print an error message to stderr."""
+ print >> sys.stderr, "ERROR:", msg % args
+
+def warn(msg, *args):
+ """Print a warning message to stderr."""
+ print >> sys.stderr, "warning:", msg % args
+
+def die (msg, *args):
+ """Print as error message to stderr and exit the program."""
+ error(msg, *args)
+ sys.exit(1)
+
+
+class ProgressIndicator(object):
+
+ """Simple progress indicator.
+
+ Displayed as a spinning character by default, but can be customized
+ by passing custom messages that overrides the spinning character.
+
+ """
+
+ States = ("|", "/", "-", "\\")
+
+ def __init__ (self, prefix = "", f = sys.stdout):
+ """Create a new ProgressIndicator, bound to the given file object."""
+ self.n = 0 # Simple progress counter
+ self.f = f # Progress is written to this file object
+ self.prev_len = 0 # Length of previous msg (to be overwritten)
+ self.prefix = prefix # Prefix prepended to each progress message
+ self.prefix_lens = [] # Stack of prefix string lengths
+
+ def pushprefix (self, prefix):
+ """Append the given prefix onto the prefix stack."""
+ self.prefix_lens.append(len(self.prefix))
+ self.prefix += prefix
+
+ def popprefix (self):
+ """Remove the last prefix from the prefix stack."""
+ prev_len = self.prefix_lens.pop()
+ self.prefix = self.prefix[:prev_len]
+
+ def __call__ (self, msg = None, lf = False):
+ """Indicate progress, possibly with a custom message."""
+ if msg is None:
+ msg = self.States[self.n % len(self.States)]
+ msg = self.prefix + msg
+ print >> self.f, "\r%-*s" % (self.prev_len, msg),
+ self.prev_len = len(msg.expandtabs())
+ if lf:
+ print >> self.f
+ self.prev_len = 0
+ self.n += 1
+
+ def finish (self, msg = "done", noprefix = False):
+ """Finalize progress indication with the given message."""
+ if noprefix:
+ self.prefix = ""
+ self(msg, True)
+
+
+def start_command (args, cwd = None, shell = False, add_env = None,
+ stdin = subprocess.PIPE, stdout = subprocess.PIPE,
+ stderr = subprocess.PIPE):
+ """Start the given command, and return a subprocess object.
+
+ This provides a simpler interface to the subprocess module.
+
+ """
+ env = None
+ if add_env is not None:
+ env = os.environ.copy()
+ env.update(add_env)
+ return subprocess.Popen(args, bufsize = 1, stdin = stdin, stdout = stdout,
+ stderr = stderr, cwd = cwd, shell = shell,
+ env = env, universal_newlines = True)
+
+
+def run_command (args, cwd = None, shell = False, add_env = None,
+ flag_error = True):
+ """Run the given command to completion, and return its results.
+
+ This provides a simpler interface to the subprocess module.
+
+ The results are formatted as a 3-tuple: (exit_code, output, errors)
+
+ If flag_error is enabled, Error messages will be produced if the
+ subprocess terminated with a non-zero exit code and/or stderr
+ output.
+
+ The other arguments are passed on to start_command().
+
+ """
+ process = start_command(args, cwd, shell, add_env)
+ (output, errors) = process.communicate()
+ exit_code = process.returncode
+ if flag_error and errors:
+ error("'%s' returned errors:\n---\n%s---", " ".join(args), errors)
+ if flag_error and exit_code:
+ error("'%s' returned exit code %i", " ".join(args), exit_code)
+ return (exit_code, output, errors)
+
+
+def file_reader_method (missing_ok = False):
+ """Decorator for simplifying reading of files.
+
+ If missing_ok is True, a failure to open a file for reading will
+ not raise the usual IOError, but instead the wrapped method will be
+ called with f == None. The method must in this case properly
+ handle f == None.
+
+ """
+ def _wrap (method):
+ """Teach given method to handle both filenames and file objects.
+
+ The given method must take a file object as its second argument
+ (the first argument being 'self', of course). This decorator
+ will take a filename given as the second argument and promote
+ it to a file object.
+
+ """
+ def _wrapped_method (self, filename, *args, **kwargs):
+ if isinstance(filename, file):
+ f = filename
+ else:
+ try:
+ f = open(filename, 'r')
+ except IOError:
+ if missing_ok:
+ f = None
+ else:
+ raise
+ try:
+ return method(self, f, *args, **kwargs)
+ finally:
+ if not isinstance(filename, file) and f:
+ f.close()
+ return _wrapped_method
+ return _wrap
+
+
+def file_writer_method (method):
+ """Decorator for simplifying writing of files.
+
+ Enables the given method to handle both filenames and file objects.
+
+ The given method must take a file object as its second argument
+ (the first argument being 'self', of course). This decorator will
+ take a filename given as the second argument and promote it to a
+ file object.
+
+ """
+ def _new_method (self, filename, *args, **kwargs):
+ if isinstance(filename, file):
+ f = filename
+ else:
+ # Make sure the containing directory exists
+ parent_dir = os.path.dirname(filename)
+ if not os.path.isdir(parent_dir):
+ os.makedirs(parent_dir)
+ f = open(filename, 'w')
+ try:
+ return method(self, f, *args, **kwargs)
+ finally:
+ if not isinstance(filename, file):
+ f.close()
+ return _new_method
projects / thirdparty / git.git / blobdiff