Mercurial > hg
view mercurial/templateutil.py @ 37728:564a3eec6e63
wireprotov2: add support for more response types
This adds types to represent error and generator responses from
server commands.
Differential Revision: https://phab.mercurial-scm.org/D3388
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Sun, 15 Apr 2018 10:37:29 -0700 |
parents | 40c7347f6848 |
children | 61cecab0cc20 |
line wrap: on
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# templateutil.py - utility for template evaluation # # Copyright 2005, 2006 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. from __future__ import absolute_import import abc import types from .i18n import _ from . import ( error, pycompat, util, ) from .utils import ( dateutil, stringutil, ) class ResourceUnavailable(error.Abort): pass class TemplateNotFound(error.Abort): pass class wrapped(object): """Object requiring extra conversion prior to displaying or processing as value Use unwrapvalue(), unwrapastype(), or unwraphybrid() to obtain the inner object. """ __metaclass__ = abc.ABCMeta @abc.abstractmethod def itermaps(self, context): """Yield each template mapping""" @abc.abstractmethod def join(self, context, mapping, sep): """Join items with the separator; Returns a bytes or (possibly nested) generator of bytes A pre-configured template may be rendered per item if this container holds unprintable items. """ @abc.abstractmethod def show(self, context, mapping): """Return a bytes or (possibly nested) generator of bytes representing the underlying object A pre-configured template may be rendered if the underlying object is not printable. """ @abc.abstractmethod def tovalue(self, context, mapping): """Move the inner value object out or create a value representation A returned value must be serializable by templaterfilters.json(). """ # stub for representing a date type; may be a real date type that can # provide a readable string value class date(object): pass class hybrid(wrapped): """Wrapper for list or dict to support legacy template This class allows us to handle both: - "{files}" (legacy command-line-specific list hack) and - "{files % '{file}\n'}" (hgweb-style with inlining and function support) and to access raw values: - "{ifcontains(file, files, ...)}", "{ifcontains(key, extras, ...)}" - "{get(extras, key)}" - "{files|json}" """ def __init__(self, gen, values, makemap, joinfmt, keytype=None): self._gen = gen # generator or function returning generator self._values = values self._makemap = makemap self._joinfmt = joinfmt self.keytype = keytype # hint for 'x in y' where type(x) is unresolved def itermaps(self, context): makemap = self._makemap for x in self._values: yield makemap(x) def join(self, context, mapping, sep): # TODO: switch gen to (context, mapping) API? return joinitems((self._joinfmt(x) for x in self._values), sep) def show(self, context, mapping): # TODO: switch gen to (context, mapping) API? gen = self._gen if gen is None: return self.join(context, mapping, ' ') if callable(gen): return gen() return gen def tovalue(self, context, mapping): # TODO: return self._values and get rid of proxy methods return self def __contains__(self, x): return x in self._values def __getitem__(self, key): return self._values[key] def __len__(self): return len(self._values) def __iter__(self): return iter(self._values) def __getattr__(self, name): if name not in (r'get', r'items', r'iteritems', r'iterkeys', r'itervalues', r'keys', r'values'): raise AttributeError(name) return getattr(self._values, name) class mappable(wrapped): """Wrapper for non-list/dict object to support map operation This class allows us to handle both: - "{manifest}" - "{manifest % '{rev}:{node}'}" - "{manifest.rev}" Unlike a hybrid, this does not simulate the behavior of the underling value. """ def __init__(self, gen, key, value, makemap): self._gen = gen # generator or function returning generator self._key = key self._value = value # may be generator of strings self._makemap = makemap def tomap(self): return self._makemap(self._key) def itermaps(self, context): yield self.tomap() def join(self, context, mapping, sep): # TODO: just copies the old behavior where a value was a generator # yielding one item, but reconsider about it. join() over a string # has no consistent result because a string may be a bytes, or a # generator yielding an item, or a generator yielding multiple items. # Preserving all of the current behaviors wouldn't make any sense. return self.show(context, mapping) def show(self, context, mapping): # TODO: switch gen to (context, mapping) API? gen = self._gen if gen is None: return pycompat.bytestr(self._value) if callable(gen): return gen() return gen def tovalue(self, context, mapping): return _unthunk(context, mapping, self._value) class _mappingsequence(wrapped): """Wrapper for sequence of template mappings This represents an inner template structure (i.e. a list of dicts), which can also be rendered by the specified named/literal template. Template mappings may be nested. """ def __init__(self, name=None, tmpl=None, sep=''): if name is not None and tmpl is not None: raise error.ProgrammingError('name and tmpl are mutually exclusive') self._name = name self._tmpl = tmpl self._defaultsep = sep def join(self, context, mapping, sep): mapsiter = _iteroverlaymaps(context, mapping, self.itermaps(context)) if self._name: itemiter = (context.process(self._name, m) for m in mapsiter) elif self._tmpl: itemiter = (context.expand(self._tmpl, m) for m in mapsiter) else: raise error.ParseError(_('not displayable without template')) return joinitems(itemiter, sep) def show(self, context, mapping): return self.join(context, mapping, self._defaultsep) def tovalue(self, context, mapping): knownres = context.knownresourcekeys() items = [] for nm in self.itermaps(context): # drop internal resources (recursively) which shouldn't be displayed lm = context.overlaymap(mapping, nm) items.append({k: unwrapvalue(context, lm, v) for k, v in nm.iteritems() if k not in knownres}) return items class mappinggenerator(_mappingsequence): """Wrapper for generator of template mappings The function ``make(context, *args)`` should return a generator of mapping dicts. """ def __init__(self, make, args=(), name=None, tmpl=None, sep=''): super(mappinggenerator, self).__init__(name, tmpl, sep) self._make = make self._args = args def itermaps(self, context): return self._make(context, *self._args) class mappinglist(_mappingsequence): """Wrapper for list of template mappings""" def __init__(self, mappings, name=None, tmpl=None, sep=''): super(mappinglist, self).__init__(name, tmpl, sep) self._mappings = mappings def itermaps(self, context): return iter(self._mappings) class mappedgenerator(wrapped): """Wrapper for generator of strings which acts as a list The function ``make(context, *args)`` should return a generator of byte strings, or a generator of (possibly nested) generators of byte strings (i.e. a generator for a list of byte strings.) """ def __init__(self, make, args=()): self._make = make self._args = args def _gen(self, context): return self._make(context, *self._args) def itermaps(self, context): raise error.ParseError(_('list of strings is not mappable')) def join(self, context, mapping, sep): return joinitems(self._gen(context), sep) def show(self, context, mapping): return self.join(context, mapping, '') def tovalue(self, context, mapping): return [stringify(context, mapping, x) for x in self._gen(context)] def hybriddict(data, key='key', value='value', fmt=None, gen=None): """Wrap data to support both dict-like and string-like operations""" prefmt = pycompat.identity if fmt is None: fmt = '%s=%s' prefmt = pycompat.bytestr return hybrid(gen, data, lambda k: {key: k, value: data[k]}, lambda k: fmt % (prefmt(k), prefmt(data[k]))) def hybridlist(data, name, fmt=None, gen=None): """Wrap data to support both list-like and string-like operations""" prefmt = pycompat.identity if fmt is None: fmt = '%s' prefmt = pycompat.bytestr return hybrid(gen, data, lambda x: {name: x}, lambda x: fmt % prefmt(x)) def unwraphybrid(context, mapping, thing): """Return an object which can be stringified possibly by using a legacy template""" if not isinstance(thing, wrapped): return thing return thing.show(context, mapping) def unwrapvalue(context, mapping, thing): """Move the inner value object out of the wrapper""" if not isinstance(thing, wrapped): return thing return thing.tovalue(context, mapping) def wraphybridvalue(container, key, value): """Wrap an element of hybrid container to be mappable The key is passed to the makemap function of the given container, which should be an item generated by iter(container). """ makemap = getattr(container, '_makemap', None) if makemap is None: return value if util.safehasattr(value, '_makemap'): # a nested hybrid list/dict, which has its own way of map operation return value return mappable(None, key, value, makemap) def compatdict(context, mapping, name, data, key='key', value='value', fmt=None, plural=None, separator=' '): """Wrap data like hybriddict(), but also supports old-style list template This exists for backward compatibility with the old-style template. Use hybriddict() for new template keywords. """ c = [{key: k, value: v} for k, v in data.iteritems()] f = _showcompatlist(context, mapping, name, c, plural, separator) return hybriddict(data, key=key, value=value, fmt=fmt, gen=f) def compatlist(context, mapping, name, data, element=None, fmt=None, plural=None, separator=' '): """Wrap data like hybridlist(), but also supports old-style list template This exists for backward compatibility with the old-style template. Use hybridlist() for new template keywords. """ f = _showcompatlist(context, mapping, name, data, plural, separator) return hybridlist(data, name=element or name, fmt=fmt, gen=f) def _showcompatlist(context, mapping, name, values, plural=None, separator=' '): """Return a generator that renders old-style list template name is name of key in template map. values is list of strings or dicts. plural is plural of name, if not simply name + 's'. separator is used to join values as a string expansion works like this, given name 'foo'. if values is empty, expand 'no_foos'. if 'foo' not in template map, return values as a string, joined by 'separator'. expand 'start_foos'. for each value, expand 'foo'. if 'last_foo' in template map, expand it instead of 'foo' for last key. expand 'end_foos'. """ if not plural: plural = name + 's' if not values: noname = 'no_' + plural if context.preload(noname): yield context.process(noname, mapping) return if not context.preload(name): if isinstance(values[0], bytes): yield separator.join(values) else: for v in values: r = dict(v) r.update(mapping) yield r return startname = 'start_' + plural if context.preload(startname): yield context.process(startname, mapping) def one(v, tag=name): vmapping = {} try: vmapping.update(v) # Python 2 raises ValueError if the type of v is wrong. Python # 3 raises TypeError. except (AttributeError, TypeError, ValueError): try: # Python 2 raises ValueError trying to destructure an e.g. # bytes. Python 3 raises TypeError. for a, b in v: vmapping[a] = b except (TypeError, ValueError): vmapping[name] = v vmapping = context.overlaymap(mapping, vmapping) return context.process(tag, vmapping) lastname = 'last_' + name if context.preload(lastname): last = values.pop() else: last = None for v in values: yield one(v) if last is not None: yield one(last, tag=lastname) endname = 'end_' + plural if context.preload(endname): yield context.process(endname, mapping) def flatten(context, mapping, thing): """Yield a single stream from a possibly nested set of iterators""" thing = unwraphybrid(context, mapping, thing) if isinstance(thing, bytes): yield thing elif isinstance(thing, str): # We can only hit this on Python 3, and it's here to guard # against infinite recursion. raise error.ProgrammingError('Mercurial IO including templates is done' ' with bytes, not strings, got %r' % thing) elif thing is None: pass elif not util.safehasattr(thing, '__iter__'): yield pycompat.bytestr(thing) else: for i in thing: i = unwraphybrid(context, mapping, i) if isinstance(i, bytes): yield i elif i is None: pass elif not util.safehasattr(i, '__iter__'): yield pycompat.bytestr(i) else: for j in flatten(context, mapping, i): yield j def stringify(context, mapping, thing): """Turn values into bytes by converting into text and concatenating them""" if isinstance(thing, bytes): return thing # retain localstr to be round-tripped return b''.join(flatten(context, mapping, thing)) def findsymbolicname(arg): """Find symbolic name for the given compiled expression; returns None if nothing found reliably""" while True: func, data = arg if func is runsymbol: return data elif func is runfilter: arg = data[0] else: return None def _unthunk(context, mapping, thing): """Evaluate a lazy byte string into value""" if not isinstance(thing, types.GeneratorType): return thing return stringify(context, mapping, thing) def evalrawexp(context, mapping, arg): """Evaluate given argument as a bare template object which may require further processing (such as folding generator of strings)""" func, data = arg return func(context, mapping, data) def evalfuncarg(context, mapping, arg): """Evaluate given argument as value type""" return _unwrapvalue(context, mapping, evalrawexp(context, mapping, arg)) # TODO: unify this with unwrapvalue() once the bug of templatefunc.join() # is fixed. we can't do that right now because join() has to take a generator # of byte strings as it is, not a lazy byte string. def _unwrapvalue(context, mapping, thing): thing = unwrapvalue(context, mapping, thing) # evalrawexp() may return string, generator of strings or arbitrary object # such as date tuple, but filter does not want generator. return _unthunk(context, mapping, thing) def evalboolean(context, mapping, arg): """Evaluate given argument as boolean, but also takes boolean literals""" func, data = arg if func is runsymbol: thing = func(context, mapping, data, default=None) if thing is None: # not a template keyword, takes as a boolean literal thing = stringutil.parsebool(data) else: thing = func(context, mapping, data) thing = unwrapvalue(context, mapping, thing) if isinstance(thing, bool): return thing # other objects are evaluated as strings, which means 0 is True, but # empty dict/list should be False as they are expected to be '' return bool(stringify(context, mapping, thing)) def evaldate(context, mapping, arg, err=None): """Evaluate given argument as a date tuple or a date string; returns a (unixtime, offset) tuple""" thing = evalrawexp(context, mapping, arg) return unwrapdate(context, mapping, thing, err) def unwrapdate(context, mapping, thing, err=None): thing = _unwrapvalue(context, mapping, thing) try: return dateutil.parsedate(thing) except AttributeError: raise error.ParseError(err or _('not a date tuple nor a string')) except error.ParseError: if not err: raise raise error.ParseError(err) def evalinteger(context, mapping, arg, err=None): thing = evalrawexp(context, mapping, arg) return unwrapinteger(context, mapping, thing, err) def unwrapinteger(context, mapping, thing, err=None): thing = _unwrapvalue(context, mapping, thing) try: return int(thing) except (TypeError, ValueError): raise error.ParseError(err or _('not an integer')) def evalstring(context, mapping, arg): return stringify(context, mapping, evalrawexp(context, mapping, arg)) def evalstringliteral(context, mapping, arg): """Evaluate given argument as string template, but returns symbol name if it is unknown""" func, data = arg if func is runsymbol: thing = func(context, mapping, data, default=data) else: thing = func(context, mapping, data) return stringify(context, mapping, thing) _unwrapfuncbytype = { None: _unwrapvalue, bytes: stringify, date: unwrapdate, int: unwrapinteger, } def unwrapastype(context, mapping, thing, typ): """Move the inner value object out of the wrapper and coerce its type""" try: f = _unwrapfuncbytype[typ] except KeyError: raise error.ProgrammingError('invalid type specified: %r' % typ) return f(context, mapping, thing) def runinteger(context, mapping, data): return int(data) def runstring(context, mapping, data): return data def _recursivesymbolblocker(key): def showrecursion(**args): raise error.Abort(_("recursive reference '%s' in template") % key) return showrecursion def runsymbol(context, mapping, key, default=''): v = context.symbol(mapping, key) if v is None: # put poison to cut recursion. we can't move this to parsing phase # because "x = {x}" is allowed if "x" is a keyword. (issue4758) safemapping = mapping.copy() safemapping[key] = _recursivesymbolblocker(key) try: v = context.process(key, safemapping) except TemplateNotFound: v = default if callable(v) and getattr(v, '_requires', None) is None: # old templatekw: expand all keywords and resources # (TODO: deprecate this after porting web template keywords to new API) props = {k: context._resources.lookup(context, mapping, k) for k in context._resources.knownkeys()} # pass context to _showcompatlist() through templatekw._showlist() props['templ'] = context props.update(mapping) return v(**pycompat.strkwargs(props)) if callable(v): # new templatekw try: return v(context, mapping) except ResourceUnavailable: # unsupported keyword is mapped to empty just like unknown keyword return None return v def runtemplate(context, mapping, template): for arg in template: yield evalrawexp(context, mapping, arg) def runfilter(context, mapping, data): arg, filt = data thing = evalrawexp(context, mapping, arg) intype = getattr(filt, '_intype', None) try: thing = unwrapastype(context, mapping, thing, intype) return filt(thing) except error.ParseError as e: raise error.ParseError(bytes(e), hint=_formatfiltererror(arg, filt)) def _formatfiltererror(arg, filt): fn = pycompat.sysbytes(filt.__name__) sym = findsymbolicname(arg) if not sym: return _("incompatible use of template filter '%s'") % fn return (_("template filter '%s' is not compatible with keyword '%s'") % (fn, sym)) def _checkeditermaps(darg, d): try: for v in d: if not isinstance(v, dict): raise TypeError yield v except TypeError: sym = findsymbolicname(darg) if sym: raise error.ParseError(_("keyword '%s' is not iterable of mappings") % sym) else: raise error.ParseError(_("%r is not iterable of mappings") % d) def _iteroverlaymaps(context, origmapping, newmappings): """Generate combined mappings from the original mapping and an iterable of partial mappings to override the original""" for i, nm in enumerate(newmappings): lm = context.overlaymap(origmapping, nm) lm['index'] = i yield lm def _applymap(context, mapping, diter, targ): for lm in _iteroverlaymaps(context, mapping, diter): yield evalrawexp(context, lm, targ) def runmap(context, mapping, data): darg, targ = data d = evalrawexp(context, mapping, darg) # TODO: a generator should be rejected because it is a thunk of lazy # string, but we can't because hgweb abuses generator as a keyword # that returns a list of dicts. # TODO: drop _checkeditermaps() and pass 'd' to mappedgenerator so it # can be restarted. if isinstance(d, wrapped): diter = d.itermaps(context) else: diter = _checkeditermaps(darg, d) return mappedgenerator(_applymap, args=(mapping, diter, targ)) def runmember(context, mapping, data): darg, memb = data d = evalrawexp(context, mapping, darg) if util.safehasattr(d, 'tomap'): lm = context.overlaymap(mapping, d.tomap()) return runsymbol(context, lm, memb) if util.safehasattr(d, 'get'): return getdictitem(d, memb) sym = findsymbolicname(darg) if sym: raise error.ParseError(_("keyword '%s' has no member") % sym) else: raise error.ParseError(_("%r has no member") % pycompat.bytestr(d)) def runnegate(context, mapping, data): data = evalinteger(context, mapping, data, _('negation needs an integer argument')) return -data def runarithmetic(context, mapping, data): func, left, right = data left = evalinteger(context, mapping, left, _('arithmetic only defined on integers')) right = evalinteger(context, mapping, right, _('arithmetic only defined on integers')) try: return func(left, right) except ZeroDivisionError: raise error.Abort(_('division by zero is not defined')) def getdictitem(dictarg, key): val = dictarg.get(key) if val is None: return return wraphybridvalue(dictarg, key, val) def joinitems(itemiter, sep): """Join items with the separator; Returns generator of bytes""" first = True for x in itemiter: if first: first = False elif sep: yield sep yield x