Mercurial > hg
view mercurial/formatter.py @ 23201:7e97bf6ee2d6
changelog: rework the delayupdate mechanism
The current way we use the 'delayupdate' mechanism is wrong. We call
'delayupdate' right after the transaction retrieval, then we call 'finalize'
right before calling 'tr.close()'. The 'finalize' call will -always- result in a
flush to disk, making the data available to all readers. But the 'tr.close()' may
be a no-op if the transaction is nested. This would result in data:
1) exposed to reader too early,
2) rolled back by other part of the transaction after such exposure
So we need to end up in a situation where we call 'finalize' a single time when
the transaction actually closes. For this purpose we need to be able to call
'delayupdate' and '_writepending' multiple times and 'finalize' once. This was
not possible with the previous state of the code.
This changeset refactors the code to makes this possible. We buffer data in memory
as much as possible and fall-back to writing to a ".a" file after the first call
to '_writepending'.
author | Pierre-Yves David <pierre-yves.david@fb.com> |
---|---|
date | Sat, 18 Oct 2014 01:12:18 -0700 |
parents | cb28d2b3db0b |
children | 0a714a1f7d5c |
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# formatter.py - generic output formatting for mercurial # # Copyright 2012 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. import cPickle from node import hex, short from i18n import _ import encoding, util class baseformatter(object): def __init__(self, ui, topic, opts): self._ui = ui self._topic = topic self._style = opts.get("style") self._template = opts.get("template") self._item = None # function to convert node to string suitable for this output self.hexfunc = hex def __nonzero__(self): '''return False if we're not doing real templating so we can skip extra work''' return True def _showitem(self): '''show a formatted item once all data is collected''' pass def startitem(self): '''begin an item in the format list''' if self._item is not None: self._showitem() self._item = {} def data(self, **data): '''insert data into item that's not shown in default output''' self._item.update(data) def write(self, fields, deftext, *fielddata, **opts): '''do default text output while assigning data to item''' for k, v in zip(fields.split(), fielddata): self._item[k] = v def condwrite(self, cond, fields, deftext, *fielddata, **opts): '''do conditional write (primarily for plain formatter)''' for k, v in zip(fields.split(), fielddata): self._item[k] = v def plain(self, text, **opts): '''show raw text for non-templated mode''' pass def end(self): '''end output for the formatter''' if self._item is not None: self._showitem() class plainformatter(baseformatter): '''the default text output scheme''' def __init__(self, ui, topic, opts): baseformatter.__init__(self, ui, topic, opts) if ui.debugflag: self.hexfunc = hex else: self.hexfunc = short def __nonzero__(self): return False def startitem(self): pass def data(self, **data): pass def write(self, fields, deftext, *fielddata, **opts): self._ui.write(deftext % fielddata, **opts) def condwrite(self, cond, fields, deftext, *fielddata, **opts): '''do conditional write''' if cond: self._ui.write(deftext % fielddata, **opts) def plain(self, text, **opts): self._ui.write(text, **opts) def end(self): pass class debugformatter(baseformatter): def __init__(self, ui, topic, opts): baseformatter.__init__(self, ui, topic, opts) self._ui.write("%s = [\n" % self._topic) def _showitem(self): self._ui.write(" " + repr(self._item) + ",\n") def end(self): baseformatter.end(self) self._ui.write("]\n") class pickleformatter(baseformatter): def __init__(self, ui, topic, opts): baseformatter.__init__(self, ui, topic, opts) self._data = [] def _showitem(self): self._data.append(self._item) def end(self): baseformatter.end(self) self._ui.write(cPickle.dumps(self._data)) def _jsonifyobj(v): if isinstance(v, tuple): return '[' + ', '.join(_jsonifyobj(e) for e in v) + ']' elif v is True: return 'true' elif v is False: return 'false' elif isinstance(v, (int, float)): return str(v) else: return '"%s"' % encoding.jsonescape(v) class jsonformatter(baseformatter): def __init__(self, ui, topic, opts): baseformatter.__init__(self, ui, topic, opts) self._ui.write("[") self._ui._first = True def _showitem(self): if self._ui._first: self._ui._first = False else: self._ui.write(",") self._ui.write("\n {\n") first = True for k, v in sorted(self._item.items()): if first: first = False else: self._ui.write(",\n") self._ui.write(' "%s": %s' % (k, _jsonifyobj(v))) self._ui.write("\n }") def end(self): baseformatter.end(self) self._ui.write("\n]\n") def formatter(ui, topic, opts): template = opts.get("template", "") if template == "json": return jsonformatter(ui, topic, opts) elif template == "pickle": return pickleformatter(ui, topic, opts) elif template == "debug": return debugformatter(ui, topic, opts) elif template != "": raise util.Abort(_("custom templates not yet supported")) elif ui.configbool('ui', 'formatdebug'): return debugformatter(ui, topic, opts) elif ui.configbool('ui', 'formatjson'): return jsonformatter(ui, topic, opts) return plainformatter(ui, topic, opts)