chiark - git - mdw - stgit/blob - stgit/out.py

   1 # -*- coding: utf-8 -*-
   2
   3 __copyright__ = """
   4 Copyright (C) 2007, Karl Hasselström <kha@treskal.com>
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License version 2 as
   8 published by the Free Software Foundation.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18 """
  19
  20 import sys
  21
  22 class MessagePrinter(object):
  23     def __init__(self):
  24         class Output(object):
  25             def __init__(self, write, flush):
  26                 self.write = write
  27                 self.flush = flush
  28                 self.at_start_of_line = True
  29                 self.level = 0
  30             def new_line(self):
  31                 """Ensure that we're at the beginning of a line."""
  32                 if not self.at_start_of_line:
  33                     self.write('\n')
  34                     self.at_start_of_line = True
  35             def single_line(self, msg, print_newline = True,
  36                             need_newline = True):
  37                 """Write a single line. Newline before and after are
  38                 separately configurable."""
  39                 if need_newline:
  40                     self.new_line()
  41                 if self.at_start_of_line:
  42                     self.write('  '*self.level)
  43                 self.write(msg)
  44                 if print_newline:
  45                     self.write('\n')
  46                     self.at_start_of_line = True
  47                 else:
  48                     self.flush()
  49                     self.at_start_of_line = False
  50             def tagged_lines(self, tag, lines):
  51                 tag += ': '
  52                 for line in lines:
  53                     self.single_line(tag + line)
  54                     tag = ' '*len(tag)
  55             def write_line(self, line):
  56                 """Write one line of text on a lines of its own, not
  57                 indented."""
  58                 self.new_line()
  59                 self.write('%s\n' % line)
  60                 self.at_start_of_line = True
  61             def write_raw(self, string):
  62                 """Write an arbitrary string, possibly containing
  63                 newlines."""
  64                 self.new_line()
  65                 self.write(string)
  66                 self.at_start_of_line = string.endswith('\n')
  67         self.__stderr = Output(sys.stderr.write, sys.stderr.flush)
  68         self.__stdout = Output(sys.stdout.write, sys.stdout.flush)
  69         if sys.stdout.isatty():
  70             self.__out = self.__stdout
  71             self.__err = self.__stdout
  72         else:
  73             self.__out = Output(lambda msg: None, lambda: None)
  74             self.__err = self.__stderr
  75     def stdout(self, line):
  76         """Write a line to stdout."""
  77         self.__stdout.write_line(line)
  78     def stdout_raw(self, string):
  79         """Write a string possibly containing newlines to stdout."""
  80         self.__stdout.write_raw(string)
  81     def err_raw(self, string):
  82         """Write a string possibly containing newlines to the error
  83         output."""
  84         self.__err.write_raw(string)
  85     def info(self, *msgs):
  86         for msg in msgs:
  87             self.__out.single_line(msg)
  88     def note(self, *msgs):
  89         self.__out.tagged_lines('Notice', msgs)
  90     def warn(self, *msgs):
  91         self.__err.tagged_lines('Warning', msgs)
  92     def error(self, *msgs):
  93         self.__err.tagged_lines('Error', msgs)
  94     def start(self, msg):
  95         """Start a long-running operation."""
  96         self.__out.single_line('%s ... ' % msg, print_newline = False)
  97         self.__out.level += 1
  98     def done(self, extramsg = None):
  99         """Finish long-running operation."""
 100         self.__out.level -= 1
 101         if extramsg:
 102             msg = 'done (%s)' % extramsg
 103         else:
 104             msg = 'done'
 105         self.__out.single_line(msg, need_newline = False)
 106
 107 out = MessagePrinter()