[gentoo-commits] portage r13706 - main/branches/prefix/pym/_emerge

[Fabian Groffen (grobian)]

Author: grobian
Date: 2009-06-27 13:12:24 +0000 (Sat, 27 Jun 2009)
New Revision: 13706

Added:
   main/branches/prefix/pym/_emerge/JobStatusDisplay.py
   main/branches/prefix/pym/_emerge/UninstallFailure.py
   main/branches/prefix/pym/_emerge/getloadavg.py
   main/branches/prefix/pym/_emerge/stdout_spinner.py
Modified:
   main/branches/prefix/pym/_emerge/__init__.py
Log:
   Merged from trunk -r13666:13667

   | 13667   | Bug #275047 - Split _emerge/__init__.py into smaller pieces  |
   | zmedico | (part 2). Thanks to Sebastian Mingramm (few)                 |
   |         | <s.mingramm@×××.de> for this patch.                          |


Copied: main/branches/prefix/pym/_emerge/JobStatusDisplay.py (from rev 13667, main/trunk/pym/_emerge/JobStatusDisplay.py)
===================================================================
--- main/branches/prefix/pym/_emerge/JobStatusDisplay.py	                        (rev 0)
+++ main/branches/prefix/pym/_emerge/JobStatusDisplay.py	2009-06-27 13:12:24 UTC (rev 13706)
@@ -0,0 +1,269 @@
+import formatter
+import os
+import sys
+import time
+
+try:
+	from cStringIO import StringIO
+except ImportError:
+	from StringIO import StringIO
+
+# for an explanation on this logic, see pym/_emerge/__init__.py
+import os
+import sys
+if os.environ.__contains__("PORTAGE_PYTHONPATH"):
+	sys.path.insert(0, os.environ["PORTAGE_PYTHONPATH"])
+else:
+	sys.path.insert(0, os.path.join(os.path.dirname(os.path.dirname(os.path.realpath(__file__))), "pym"))
+import portage
+
+from portage.output import xtermTitle
+
+from _emerge.getloadavg import getloadavg
+
+class JobStatusDisplay(object):
+
+	_bound_properties = ("curval", "failed", "running")
+	_jobs_column_width = 48
+
+	# Don't update the display unless at least this much
+	# time has passed, in units of seconds.
+	_min_display_latency = 2
+
+	_default_term_codes = {
+		'cr'  : '\r',
+		'el'  : '\x1b[K',
+		'nel' : '\n',
+	}
+
+	_termcap_name_map = {
+		'carriage_return' : 'cr',
+		'clr_eol'         : 'el',
+		'newline'         : 'nel',
+	}
+
+	def __init__(self, out=sys.stdout, quiet=False, xterm_titles=True):
+		object.__setattr__(self, "out", out)
+		object.__setattr__(self, "quiet", quiet)
+		object.__setattr__(self, "xterm_titles", xterm_titles)
+		object.__setattr__(self, "maxval", 0)
+		object.__setattr__(self, "merges", 0)
+		object.__setattr__(self, "_changed", False)
+		object.__setattr__(self, "_displayed", False)
+		object.__setattr__(self, "_last_display_time", 0)
+		object.__setattr__(self, "width", 80)
+		self.reset()
+
+		isatty = hasattr(out, "isatty") and out.isatty()
+		object.__setattr__(self, "_isatty", isatty)
+		if not isatty or not self._init_term():
+			term_codes = {}
+			for k, capname in self._termcap_name_map.iteritems():
+				term_codes[k] = self._default_term_codes[capname]
+			object.__setattr__(self, "_term_codes", term_codes)
+		encoding = sys.getdefaultencoding()
+		for k, v in self._term_codes.items():
+			if not isinstance(v, basestring):
+				self._term_codes[k] = v.decode(encoding, 'replace')
+
+	def _init_term(self):
+		"""
+		Initialize term control codes.
+		@rtype: bool
+		@returns: True if term codes were successfully initialized,
+			False otherwise.
+		"""
+
+		term_type = os.environ.get("TERM", "vt100")
+		tigetstr = None
+
+		try:
+			import curses
+			try:
+				curses.setupterm(term_type, self.out.fileno())
+				tigetstr = curses.tigetstr
+			except curses.error:
+				pass
+		except ImportError:
+			pass
+
+		if tigetstr is None:
+			return False
+
+		term_codes = {}
+		for k, capname in self._termcap_name_map.iteritems():
+			code = tigetstr(capname)
+			if code is None:
+				code = self._default_term_codes[capname]
+			term_codes[k] = code
+		object.__setattr__(self, "_term_codes", term_codes)
+		return True
+
+	def _format_msg(self, msg):
+		return ">>> %s" % msg
+
+	def _erase(self):
+		self.out.write(
+			self._term_codes['carriage_return'] + \
+			self._term_codes['clr_eol'])
+		self.out.flush()
+		self._displayed = False
+
+	def _display(self, line):
+		self.out.write(line)
+		self.out.flush()
+		self._displayed = True
+
+	def _update(self, msg):
+
+		out = self.out
+		if not self._isatty:
+			out.write(self._format_msg(msg) + self._term_codes['newline'])
+			self.out.flush()
+			self._displayed = True
+			return
+
+		if self._displayed:
+			self._erase()
+
+		self._display(self._format_msg(msg))
+
+	def displayMessage(self, msg):
+
+		was_displayed = self._displayed
+
+		if self._isatty and self._displayed:
+			self._erase()
+
+		self.out.write(self._format_msg(msg) + self._term_codes['newline'])
+		self.out.flush()
+		self._displayed = False
+
+		if was_displayed:
+			self._changed = True
+			self.display()
+
+	def reset(self):
+		self.maxval = 0
+		self.merges = 0
+		for name in self._bound_properties:
+			object.__setattr__(self, name, 0)
+
+		if self._displayed:
+			self.out.write(self._term_codes['newline'])
+			self.out.flush()
+			self._displayed = False
+
+	def __setattr__(self, name, value):
+		old_value = getattr(self, name)
+		if value == old_value:
+			return
+		object.__setattr__(self, name, value)
+		if name in self._bound_properties:
+			self._property_change(name, old_value, value)
+
+	def _property_change(self, name, old_value, new_value):
+		self._changed = True
+		self.display()
+
+	def _load_avg_str(self):
+		try:
+			avg = getloadavg()
+		except OSError:
+			return 'unknown'
+
+		max_avg = max(avg)
+
+		if max_avg < 10:
+			digits = 2
+		elif max_avg < 100:
+			digits = 1
+		else:
+			digits = 0
+
+		return ", ".join(("%%.%df" % digits ) % x for x in avg)
+
+	def display(self):
+		"""
+		Display status on stdout, but only if something has
+		changed since the last call.
+		"""
+
+		if self.quiet:
+			return
+
+		current_time = time.time()
+		time_delta = current_time - self._last_display_time
+		if self._displayed and \
+			not self._changed:
+			if not self._isatty:
+				return
+			if time_delta < self._min_display_latency:
+				return
+
+		self._last_display_time = current_time
+		self._changed = False
+		self._display_status()
+
+	def _display_status(self):
+		# Don't use len(self._completed_tasks) here since that also
+		# can include uninstall tasks.
+		curval_str = str(self.curval)
+		maxval_str = str(self.maxval)
+		running_str = str(self.running)
+		failed_str = str(self.failed)
+		load_avg_str = self._load_avg_str()
+
+		color_output = StringIO()
+		plain_output = StringIO()
+		style_file = portage.output.ConsoleStyleFile(color_output)
+		style_file.write_listener = plain_output
+		style_writer = portage.output.StyleWriter(file=style_file, maxcol=9999)
+		style_writer.style_listener = style_file.new_styles
+		f = formatter.AbstractFormatter(style_writer)
+
+		number_style = "INFORM"
+		f.add_literal_data("Jobs: ")
+		f.push_style(number_style)
+		f.add_literal_data(curval_str)
+		f.pop_style()
+		f.add_literal_data(" of ")
+		f.push_style(number_style)
+		f.add_literal_data(maxval_str)
+		f.pop_style()
+		f.add_literal_data(" complete")
+
+		if self.running:
+			f.add_literal_data(", ")
+			f.push_style(number_style)
+			f.add_literal_data(running_str)
+			f.pop_style()
+			f.add_literal_data(" running")
+
+		if self.failed:
+			f.add_literal_data(", ")
+			f.push_style(number_style)
+			f.add_literal_data(failed_str)
+			f.pop_style()
+			f.add_literal_data(" failed")
+
+		padding = self._jobs_column_width - len(plain_output.getvalue())
+		if padding > 0:
+			f.add_literal_data(padding * " ")
+
+		f.add_literal_data("Load avg: ")
+		f.add_literal_data(load_avg_str)
+
+		# Truncate to fit width, to avoid making the terminal scroll if the
+		# line overflows (happens when the load average is large).
+		plain_output = plain_output.getvalue()
+		if self._isatty and len(plain_output) > self.width:
+			# Use plain_output here since it's easier to truncate
+			# properly than the color output which contains console
+			# color codes.
+			self._update(plain_output[:self.width])
+		else:
+			self._update(color_output.getvalue())
+
+		if self.xterm_titles:
+			xtermTitle(" ".join(plain_output.split()))

Copied: main/branches/prefix/pym/_emerge/UninstallFailure.py (from rev 13667, main/trunk/pym/_emerge/UninstallFailure.py)
===================================================================
--- main/branches/prefix/pym/_emerge/UninstallFailure.py	                        (rev 0)
+++ main/branches/prefix/pym/_emerge/UninstallFailure.py	2009-06-27 13:12:24 UTC (rev 13706)
@@ -0,0 +1,19 @@
+# for an explanation on this logic, see pym/_emerge/__init__.py
+import os
+import sys
+if os.environ.__contains__("PORTAGE_PYTHONPATH"):
+	sys.path.insert(0, os.environ["PORTAGE_PYTHONPATH"])
+else:
+	sys.path.insert(0, os.path.join(os.path.dirname(os.path.dirname(os.path.realpath(__file__))), "pym"))
+import portage
+	
+class UninstallFailure(portage.exception.PortageException):
+	"""
+	An instance of this class is raised by unmerge() when
+	an uninstallation fails.
+	"""
+	status = 1
+	def __init__(self, *pargs):
+		portage.exception.PortageException.__init__(self, pargs)
+		if pargs:
+			self.status = pargs[0]

Modified: main/branches/prefix/pym/_emerge/__init__.py
===================================================================
--- main/branches/prefix/pym/_emerge/__init__.py	2009-06-27 13:02:34 UTC (rev 13705)
+++ main/branches/prefix/pym/_emerge/__init__.py	2009-06-27 13:12:24 UTC (rev 13706)
@@ -96,87 +96,11 @@
 from _emerge.PollSelectAdapter import PollSelectAdapter
 from _emerge.SequentialTaskQueue import SequentialTaskQueue
 from _emerge.ProgressHandler import ProgressHandler
+from _emerge.stdout_spinner import stdout_spinner
+from _emerge.UninstallFailure import UninstallFailure
+from _emerge.JobStatusDisplay import JobStatusDisplay
+from _emerge.getloadavg import getloadavg
 
-try:
-	from cStringIO import StringIO
-except ImportError:
-	from StringIO import StringIO
-
-class stdout_spinner(object):
-	scroll_msgs = [
-		"Gentoo Rocks ("+platform.system()+")",
-		"Thank you for using Gentoo. :)",
-		"Are you actually trying to read this?",
-		"How many times have you stared at this?",
-		"We are generating the cache right now",
-		"You are paying too much attention.",
-		"A theory is better than its explanation.",
-		"Phasers locked on target, Captain.",
-		"Thrashing is just virtual crashing.",
-		"To be is to program.",
-		"Real Users hate Real Programmers.",
-		"When all else fails, read the instructions.",
-		"Functionality breeds Contempt.",
-		"The future lies ahead.",
-		"3.1415926535897932384626433832795028841971694",
-		"Sometimes insanity is the only alternative.",
-		"Inaccuracy saves a world of explanation.",
-	]
-
-	twirl_sequence = "/-\\|/-\\|/-\\|/-\\|\\-/|\\-/|\\-/|\\-/|"
-
-	def __init__(self):
-		self.spinpos = 0
-		self.update = self.update_twirl
-		self.scroll_sequence = self.scroll_msgs[
-			int(time.time() * 100) % len(self.scroll_msgs)]
-		self.last_update = 0
-		self.min_display_latency = 0.05
-
-	def _return_early(self):
-		"""
-		Flushing ouput to the tty too frequently wastes cpu time. Therefore,
-		each update* method should return without doing any output when this
-		method returns True.
-		"""
-		cur_time = time.time()
-		if cur_time - self.last_update < self.min_display_latency:
-			return True
-		self.last_update = cur_time
-		return False
-
-	def update_basic(self):
-		self.spinpos = (self.spinpos + 1) % 500
-		if self._return_early():
-			return
-		if (self.spinpos % 100) == 0:
-			if self.spinpos == 0:
-				sys.stdout.write(". ")
-			else:
-				sys.stdout.write(".")
-		sys.stdout.flush()
-
-	def update_scroll(self):
-		if self._return_early():
-			return
-		if(self.spinpos >= len(self.scroll_sequence)):
-			sys.stdout.write(darkgreen(" \b\b\b" + self.scroll_sequence[
-				len(self.scroll_sequence) - 1 - (self.spinpos % len(self.scroll_sequence))]))
-		else:
-			sys.stdout.write(green("\b " + self.scroll_sequence[self.spinpos]))
-		sys.stdout.flush()
-		self.spinpos = (self.spinpos + 1) % (2 * len(self.scroll_sequence))
-
-	def update_twirl(self):
-		self.spinpos = (self.spinpos + 1) % len(self.twirl_sequence)
-		if self._return_early():
-			return
-		sys.stdout.write("\b\b " + self.twirl_sequence[self.spinpos])
-		sys.stdout.flush()
-
-	def update_quiet(self):
-		return
-
 def userquery(prompt, responses=None, colours=None):
 	"""Displays a prompt and a set of responses, then waits for a response
 	which is checked against the responses and the first to match is
@@ -6600,29 +6524,6 @@
 		return select.poll()
 	return PollSelectAdapter()
 
-getloadavg = getattr(os, "getloadavg", None)
-if getloadavg is None:
-	def getloadavg():
-		"""
-		Uses /proc/loadavg to emulate os.getloadavg().
-		Raises OSError if the load average was unobtainable.
-		"""
-		try:
-			loadavg_str = open('/proc/loadavg').readline()
-		except IOError:
-			# getloadavg() is only supposed to raise OSError, so convert
-			raise OSError('unknown')
-		loadavg_split = loadavg_str.split()
-		if len(loadavg_split) < 3:
-			raise OSError('unknown')
-		loadavg_floats = []
-		for i in xrange(3):
-			try:
-				loadavg_floats.append(float(loadavg_split[i]))
-			except ValueError:
-				raise OSError('unknown')
-		return tuple(loadavg_floats)
-
 class PollScheduler(object):
 
 	class _sched_iface_class(SlotObject):
@@ -6910,253 +6811,6 @@
 	def add(self, task):
 		self._queue.add(task)
 
-class JobStatusDisplay(object):
-
-	_bound_properties = ("curval", "failed", "running")
-	_jobs_column_width = 48
-
-	# Don't update the display unless at least this much
-	# time has passed, in units of seconds.
-	_min_display_latency = 2
-
-	_default_term_codes = {
-		'cr'  : '\r',
-		'el'  : '\x1b[K',
-		'nel' : '\n',
-	}
-
-	_termcap_name_map = {
-		'carriage_return' : 'cr',
-		'clr_eol'         : 'el',
-		'newline'         : 'nel',
-	}
-
-	def __init__(self, out=sys.stdout, quiet=False, xterm_titles=True):
-		object.__setattr__(self, "out", out)
-		object.__setattr__(self, "quiet", quiet)
-		object.__setattr__(self, "xterm_titles", xterm_titles)
-		object.__setattr__(self, "maxval", 0)
-		object.__setattr__(self, "merges", 0)
-		object.__setattr__(self, "_changed", False)
-		object.__setattr__(self, "_displayed", False)
-		object.__setattr__(self, "_last_display_time", 0)
-		object.__setattr__(self, "width", 80)
-		self.reset()
-
-		isatty = hasattr(out, "isatty") and out.isatty()
-		object.__setattr__(self, "_isatty", isatty)
-		if not isatty or not self._init_term():
-			term_codes = {}
-			for k, capname in self._termcap_name_map.iteritems():
-				term_codes[k] = self._default_term_codes[capname]
-			object.__setattr__(self, "_term_codes", term_codes)
-		encoding = sys.getdefaultencoding()
-		for k, v in self._term_codes.items():
-			if not isinstance(v, basestring):
-				self._term_codes[k] = v.decode(encoding, 'replace')
-
-	def _init_term(self):
-		"""
-		Initialize term control codes.
-		@rtype: bool
-		@returns: True if term codes were successfully initialized,
-			False otherwise.
-		"""
-
-		term_type = os.environ.get("TERM", "vt100")
-		tigetstr = None
-
-		try:
-			import curses
-			try:
-				curses.setupterm(term_type, self.out.fileno())
-				tigetstr = curses.tigetstr
-			except curses.error:
-				pass
-		except ImportError:
-			pass
-
-		if tigetstr is None:
-			return False
-
-		term_codes = {}
-		for k, capname in self._termcap_name_map.iteritems():
-			code = tigetstr(capname)
-			if code is None:
-				code = self._default_term_codes[capname]
-			term_codes[k] = code
-		object.__setattr__(self, "_term_codes", term_codes)
-		return True
-
-	def _format_msg(self, msg):
-		return ">>> %s" % msg
-
-	def _erase(self):
-		self.out.write(
-			self._term_codes['carriage_return'] + \
-			self._term_codes['clr_eol'])
-		self.out.flush()
-		self._displayed = False
-
-	def _display(self, line):
-		self.out.write(line)
-		self.out.flush()
-		self._displayed = True
-
-	def _update(self, msg):
-
-		out = self.out
-		if not self._isatty:
-			out.write(self._format_msg(msg) + self._term_codes['newline'])
-			self.out.flush()
-			self._displayed = True
-			return
-
-		if self._displayed:
-			self._erase()
-
-		self._display(self._format_msg(msg))
-
-	def displayMessage(self, msg):
-
-		was_displayed = self._displayed
-
-		if self._isatty and self._displayed:
-			self._erase()
-
-		self.out.write(self._format_msg(msg) + self._term_codes['newline'])
-		self.out.flush()
-		self._displayed = False
-
-		if was_displayed:
-			self._changed = True
-			self.display()
-
-	def reset(self):
-		self.maxval = 0
-		self.merges = 0
-		for name in self._bound_properties:
-			object.__setattr__(self, name, 0)
-
-		if self._displayed:
-			self.out.write(self._term_codes['newline'])
-			self.out.flush()
-			self._displayed = False
-
-	def __setattr__(self, name, value):
-		old_value = getattr(self, name)
-		if value == old_value:
-			return
-		object.__setattr__(self, name, value)
-		if name in self._bound_properties:
-			self._property_change(name, old_value, value)
-
-	def _property_change(self, name, old_value, new_value):
-		self._changed = True
-		self.display()
-
-	def _load_avg_str(self):
-		try:
-			avg = getloadavg()
-		except OSError:
-			return 'unknown'
-
-		max_avg = max(avg)
-
-		if max_avg < 10:
-			digits = 2
-		elif max_avg < 100:
-			digits = 1
-		else:
-			digits = 0
-
-		return ", ".join(("%%.%df" % digits ) % x for x in avg)
-
-	def display(self):
-		"""
-		Display status on stdout, but only if something has
-		changed since the last call.
-		"""
-
-		if self.quiet:
-			return
-
-		current_time = time.time()
-		time_delta = current_time - self._last_display_time
-		if self._displayed and \
-			not self._changed:
-			if not self._isatty:
-				return
-			if time_delta < self._min_display_latency:
-				return
-
-		self._last_display_time = current_time
-		self._changed = False
-		self._display_status()
-
-	def _display_status(self):
-		# Don't use len(self._completed_tasks) here since that also
-		# can include uninstall tasks.
-		curval_str = str(self.curval)
-		maxval_str = str(self.maxval)
-		running_str = str(self.running)
-		failed_str = str(self.failed)
-		load_avg_str = self._load_avg_str()
-
-		color_output = StringIO()
-		plain_output = StringIO()
-		style_file = portage.output.ConsoleStyleFile(color_output)
-		style_file.write_listener = plain_output
-		style_writer = portage.output.StyleWriter(file=style_file, maxcol=9999)
-		style_writer.style_listener = style_file.new_styles
-		f = formatter.AbstractFormatter(style_writer)
-
-		number_style = "INFORM"
-		f.add_literal_data("Jobs: ")
-		f.push_style(number_style)
-		f.add_literal_data(curval_str)
-		f.pop_style()
-		f.add_literal_data(" of ")
-		f.push_style(number_style)
-		f.add_literal_data(maxval_str)
-		f.pop_style()
-		f.add_literal_data(" complete")
-
-		if self.running:
-			f.add_literal_data(", ")
-			f.push_style(number_style)
-			f.add_literal_data(running_str)
-			f.pop_style()
-			f.add_literal_data(" running")
-
-		if self.failed:
-			f.add_literal_data(", ")
-			f.push_style(number_style)
-			f.add_literal_data(failed_str)
-			f.pop_style()
-			f.add_literal_data(" failed")
-
-		padding = self._jobs_column_width - len(plain_output.getvalue())
-		if padding > 0:
-			f.add_literal_data(padding * " ")
-
-		f.add_literal_data("Load avg: ")
-		f.add_literal_data(load_avg_str)
-
-		# Truncate to fit width, to avoid making the terminal scroll if the
-		# line overflows (happens when the load average is large).
-		plain_output = plain_output.getvalue()
-		if self._isatty and len(plain_output) > self.width:
-			# Use plain_output here since it's easier to truncate
-			# properly than the color output which contains console
-			# color codes.
-			self._update(plain_output[:self.width])
-		else:
-			self._update(color_output.getvalue())
-
-		if self.xterm_titles:
-			xtermTitle(" ".join(plain_output.split()))
-
 class Scheduler(PollScheduler):
 
 	_opts_ignore_blockers = \
@@ -8907,17 +8561,6 @@
 
 		self._schedule()
 
-class UninstallFailure(portage.exception.PortageException):
-	"""
-	An instance of this class is raised by unmerge() when
-	an uninstallation fails.
-	"""
-	status = 1
-	def __init__(self, *pargs):
-		portage.exception.PortageException.__init__(self, pargs)
-		if pargs:
-			self.status = pargs[0]
-
 def unmerge(root_config, myopts, unmerge_action,
 	unmerge_files, ldpath_mtimes, autoclean=0,
 	clean_world=1, clean_delay=1, ordered=0, raise_on_error=0,

Copied: main/branches/prefix/pym/_emerge/getloadavg.py (from rev 13667, main/trunk/pym/_emerge/getloadavg.py)
===================================================================
--- main/branches/prefix/pym/_emerge/getloadavg.py	                        (rev 0)
+++ main/branches/prefix/pym/_emerge/getloadavg.py	2009-06-27 13:12:24 UTC (rev 13706)
@@ -0,0 +1,24 @@
+import os 
+
+getloadavg = getattr(os, "getloadavg", None)
+if getloadavg is None:
+	def getloadavg():
+		"""
+		Uses /proc/loadavg to emulate os.getloadavg().
+		Raises OSError if the load average was unobtainable.
+		"""
+		try:
+			loadavg_str = open('/proc/loadavg').readline()
+		except IOError:
+			# getloadavg() is only supposed to raise OSError, so convert
+			raise OSError('unknown')
+		loadavg_split = loadavg_str.split()
+		if len(loadavg_split) < 3:
+			raise OSError('unknown')
+		loadavg_floats = []
+		for i in xrange(3):
+			try:
+				loadavg_floats.append(float(loadavg_split[i]))
+			except ValueError:
+				raise OSError('unknown')
+		return tuple(loadavg_floats)

Copied: main/branches/prefix/pym/_emerge/stdout_spinner.py (from rev 13667, main/trunk/pym/_emerge/stdout_spinner.py)
===================================================================
--- main/branches/prefix/pym/_emerge/stdout_spinner.py	                        (rev 0)
+++ main/branches/prefix/pym/_emerge/stdout_spinner.py	2009-06-27 13:12:24 UTC (rev 13706)
@@ -0,0 +1,80 @@
+import platform
+import sys
+import time
+
+from portage.output import darkgreen, green
+
+class stdout_spinner(object):
+	scroll_msgs = [
+		"Gentoo Rocks ("+platform.system()+")",
+		"Thank you for using Gentoo. :)",
+		"Are you actually trying to read this?",
+		"How many times have you stared at this?",
+		"We are generating the cache right now",
+		"You are paying too much attention.",
+		"A theory is better than its explanation.",
+		"Phasers locked on target, Captain.",
+		"Thrashing is just virtual crashing.",
+		"To be is to program.",
+		"Real Users hate Real Programmers.",
+		"When all else fails, read the instructions.",
+		"Functionality breeds Contempt.",
+		"The future lies ahead.",
+		"3.1415926535897932384626433832795028841971694",
+		"Sometimes insanity is the only alternative.",
+		"Inaccuracy saves a world of explanation.",
+	]
+
+	twirl_sequence = "/-\\|/-\\|/-\\|/-\\|\\-/|\\-/|\\-/|\\-/|"
+
+	def __init__(self):
+		self.spinpos = 0
+		self.update = self.update_twirl
+		self.scroll_sequence = self.scroll_msgs[
+			int(time.time() * 100) % len(self.scroll_msgs)]
+		self.last_update = 0
+		self.min_display_latency = 0.05
+
+	def _return_early(self):
+		"""
+		Flushing ouput to the tty too frequently wastes cpu time. Therefore,
+		each update* method should return without doing any output when this
+		method returns True.
+		"""
+		cur_time = time.time()
+		if cur_time - self.last_update < self.min_display_latency:
+			return True
+		self.last_update = cur_time
+		return False
+
+	def update_basic(self):
+		self.spinpos = (self.spinpos + 1) % 500
+		if self._return_early():
+			return
+		if (self.spinpos % 100) == 0:
+			if self.spinpos == 0:
+				sys.stdout.write(". ")
+			else:
+				sys.stdout.write(".")
+		sys.stdout.flush()
+
+	def update_scroll(self):
+		if self._return_early():
+			return
+		if(self.spinpos >= len(self.scroll_sequence)):
+			sys.stdout.write(darkgreen(" \b\b\b" + self.scroll_sequence[
+				len(self.scroll_sequence) - 1 - (self.spinpos % len(self.scroll_sequence))]))
+		else:
+			sys.stdout.write(green("\b " + self.scroll_sequence[self.spinpos]))
+		sys.stdout.flush()
+		self.spinpos = (self.spinpos + 1) % (2 * len(self.scroll_sequence))
+
+	def update_twirl(self):
+		self.spinpos = (self.spinpos + 1) % len(self.twirl_sequence)
+		if self._return_early():
+			return
+		sys.stdout.write("\b\b " + self.twirl_sequence[self.spinpos])
+		sys.stdout.flush()
+
+	def update_quiet(self):
+		return