view mercurial/progress.py @ 31793:69d8fcf20014

help: document bundle specifications

I softly formalized the concept of a "bundle specification" a while
ago when I was working on clone bundles and stream clone bundles and
wanted a more robust way to define what exactly is in a bundle file.

The concept has existed for a while. Since it is part of the clone
bundles feature and exposed to the user via the "-t" argument to
`hg bundle`, it is something we need to support for the long haul.

After the 4.1 release, I heard a few people comment that they didn't
realize you could generate zstd bundles with `hg bundle`. I'm
partially to blame for not documenting it in bundle's docstring.

Additionally, I added a hacky, experimental feature for controlling
the compression level of bundles in 76104a4899ad. As the commit
message says, I went with a quick and dirty solution out of time
constraints. Furthermore, I wanted to eventually store this
configuration in the "bundlespec" so it could be made more flexible.

Given:

a) bundlespecs are here to stay
b) we don't have great documentation over what they are, despite being
   a user-facing feature
c) the list of available compression engines and their behavior isn't
   exposed
d) we need an extensible place to modify behavior of compression
   engines

I want to move forward with formalizing bundlespecs as a user-facing
feature. This commit does that by introducing a "bundlespec" help
page. Leaning on the just-added compression engine documentation
and API, the topic also conveniently lists available compression
engines and details about them. This makes features like zstd
bundle compression more discoverable. e.g. you can now
`hg help -k zstd` and it lists the "bundlespec" topic.

# progress.py progress bars related code
#
# Copyright (C) 2010 Augie Fackler <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import threading
import time

from .i18n import _
from . import encoding

def spacejoin(*args):
    return ' '.join(s for s in args if s)

def shouldprint(ui):
    return not (ui.quiet or ui.plain('progress')) and (
        ui._isatty(ui.ferr) or ui.configbool('progress', 'assume-tty'))

def fmtremaining(seconds):
    """format a number of remaining seconds in human readable way

    This will properly display seconds, minutes, hours, days if needed"""
    if seconds < 60:
        # i18n: format XX seconds as "XXs"
        return _("%02ds") % (seconds)
    minutes = seconds // 60
    if minutes < 60:
        seconds -= minutes * 60
        # i18n: format X minutes and YY seconds as "XmYYs"
        return _("%dm%02ds") % (minutes, seconds)
    # we're going to ignore seconds in this case
    minutes += 1
    hours = minutes // 60
    minutes -= hours * 60
    if hours < 30:
        # i18n: format X hours and YY minutes as "XhYYm"
        return _("%dh%02dm") % (hours, minutes)
    # we're going to ignore minutes in this case
    hours += 1
    days = hours // 24
    hours -= days * 24
    if days < 15:
        # i18n: format X days and YY hours as "XdYYh"
        return _("%dd%02dh") % (days, hours)
    # we're going to ignore hours in this case
    days += 1
    weeks = days // 7
    days -= weeks * 7
    if weeks < 55:
        # i18n: format X weeks and YY days as "XwYYd"
        return _("%dw%02dd") % (weeks, days)
    # we're going to ignore days and treat a year as 52 weeks
    weeks += 1
    years = weeks // 52
    weeks -= years * 52
    # i18n: format X years and YY weeks as "XyYYw"
    return _("%dy%02dw") % (years, weeks)

class progbar(object):
    def __init__(self, ui):
        self.ui = ui
        self._refreshlock = threading.Lock()
        self.resetstate()

    def resetstate(self):
        self.topics = []
        self.topicstates = {}
        self.starttimes = {}
        self.startvals = {}
        self.printed = False
        self.lastprint = time.time() + float(self.ui.config(
            'progress', 'delay', default=3))
        self.curtopic = None
        self.lasttopic = None
        self.indetcount = 0
        self.refresh = float(self.ui.config(
            'progress', 'refresh', default=0.1))
        self.changedelay = max(3 * self.refresh,
                               float(self.ui.config(
                                   'progress', 'changedelay', default=1)))
        self.order = self.ui.configlist(
            'progress', 'format',
            default=['topic', 'bar', 'number', 'estimate'])

    def show(self, now, topic, pos, item, unit, total):
        if not shouldprint(self.ui):
            return
        termwidth = self.width()
        self.printed = True
        head = ''
        needprogress = False
        tail = ''
        for indicator in self.order:
            add = ''
            if indicator == 'topic':
                add = topic
            elif indicator == 'number':
                if total:
                    add = ('% ' + str(len(str(total))) +
                           's/%s') % (pos, total)
                else:
                    add = str(pos)
            elif indicator.startswith('item') and item:
                slice = 'end'
                if '-' in indicator:
                    wid = int(indicator.split('-')[1])
                elif '+' in indicator:
                    slice = 'beginning'
                    wid = int(indicator.split('+')[1])
                else:
                    wid = 20
                if slice == 'end':
                    add = encoding.trim(item, wid, leftside=True)
                else:
                    add = encoding.trim(item, wid)
                add += (wid - encoding.colwidth(add)) * ' '
            elif indicator == 'bar':
                add = ''
                needprogress = True
            elif indicator == 'unit' and unit:
                add = unit
            elif indicator == 'estimate':
                add = self.estimate(topic, pos, total, now)
            elif indicator == 'speed':
                add = self.speed(topic, pos, unit, now)
            if not needprogress:
                head = spacejoin(head, add)
            else:
                tail = spacejoin(tail, add)
        if needprogress:
            used = 0
            if head:
                used += encoding.colwidth(head) + 1
            if tail:
                used += encoding.colwidth(tail) + 1
            progwidth = termwidth - used - 3
            if total and pos <= total:
                amt = pos * progwidth // total
                bar = '=' * (amt - 1)
                if amt > 0:
                    bar += '>'
                bar += ' ' * (progwidth - amt)
            else:
                progwidth -= 3
                self.indetcount += 1
                # mod the count by twice the width so we can make the
                # cursor bounce between the right and left sides
                amt = self.indetcount % (2 * progwidth)
                amt -= progwidth
                bar = (' ' * int(progwidth - abs(amt)) + '<=>' +
                       ' ' * int(abs(amt)))
            prog = ''.join(('[', bar , ']'))
            out = spacejoin(head, prog, tail)
        else:
            out = spacejoin(head, tail)
        self.ui.ferr.write('\r' + encoding.trim(out, termwidth))
        self.lasttopic = topic
        self.ui.ferr.flush()

    def clear(self):
        if not self.printed or not self.lastprint or not shouldprint(self.ui):
            return
        self.ui.ferr.write('\r%s\r' % (' ' * self.width()))
        if self.printed:
            # force immediate re-paint of progress bar
            self.lastprint = 0

    def complete(self):
        if not shouldprint(self.ui):
            return
        if self.ui.configbool('progress', 'clear-complete', default=True):
            self.clear()
        else:
            self.ui.ferr.write('\n')
        self.ui.ferr.flush()

    def width(self):
        tw = self.ui.termwidth()
        return min(int(self.ui.config('progress', 'width', default=tw)), tw)

    def estimate(self, topic, pos, total, now):
        if total is None:
            return ''
        initialpos = self.startvals[topic]
        target = total - initialpos
        delta = pos - initialpos
        if delta > 0:
            elapsed = now - self.starttimes[topic]
            # experimental config: progress.estimate
            if elapsed > float(
                self.ui.config('progress', 'estimate', default=2)):
                seconds = (elapsed * (target - delta)) // delta + 1
                return fmtremaining(seconds)
        return ''

    def speed(self, topic, pos, unit, now):
        initialpos = self.startvals[topic]
        delta = pos - initialpos
        elapsed = now - self.starttimes[topic]
        if elapsed > float(
            self.ui.config('progress', 'estimate', default=2)):
            return _('%d %s/sec') % (delta / elapsed, unit)
        return ''

    def _oktoprint(self, now):
        '''Check if conditions are met to print - e.g. changedelay elapsed'''
        if (self.lasttopic is None # first time we printed
            # not a topic change
            or self.curtopic == self.lasttopic
            # it's been long enough we should print anyway
            or now - self.lastprint >= self.changedelay):
            return True
        else:
            return False

    def progress(self, topic, pos, item='', unit='', total=None):
        now = time.time()
        self._refreshlock.acquire()
        try:
            if pos is None:
                self.starttimes.pop(topic, None)
                self.startvals.pop(topic, None)
                self.topicstates.pop(topic, None)
                # reset the progress bar if this is the outermost topic
                if self.topics and self.topics[0] == topic and self.printed:
                    self.complete()
                    self.resetstate()
                # truncate the list of topics assuming all topics within
                # this one are also closed
                if topic in self.topics:
                    self.topics = self.topics[:self.topics.index(topic)]
                    # reset the last topic to the one we just unwound to,
                    # so that higher-level topics will be stickier than
                    # lower-level topics
                    if self.topics:
                        self.lasttopic = self.topics[-1]
                    else:
                        self.lasttopic = None
            else:
                if topic not in self.topics:
                    self.starttimes[topic] = now
                    self.startvals[topic] = pos
                    self.topics.append(topic)
                self.topicstates[topic] = pos, item, unit, total
                self.curtopic = topic
                if now - self.lastprint >= self.refresh and self.topics:
                    if self._oktoprint(now):
                        self.lastprint = now
                        self.show(now, topic, *self.topicstates[topic])
        finally:
            self._refreshlock.release()