Initial source commit to grit-i18n project.

grit/clique.py

+#!/usr/bin/python2.4
+# Copyright (c) 2011 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+'''Collections of messages and their translations, called cliques.  Also
+collections of cliques (uber-cliques).
+'''
+
+import types
+
+from grit import constants
+from grit import exception
+from grit import pseudo
+from grit import pseudo_rtl
+from grit import tclib
+
+
+class UberClique(object):
+  '''A factory (NOT a singleton factory) for making cliques.  It has several
+  methods for working with the cliques created using the factory.
+  '''
+
+  def __init__(self):
+    # A map from message ID to list of cliques whose source messages have
+    # that ID.  This will contain all cliques created using this factory.
+    # Different messages can have the same ID because they have the
+    # same translateable portion and placeholder names, but occur in different
+    # places in the resource tree.
+    self.cliques_ = {}
+
+    # A map of clique IDs to list of languages to indicate translations where we
+    # fell back to English.
+    self.fallback_translations_ = {}
+
+    # A map of clique IDs to list of languages to indicate missing translations.
+    self.missing_translations_ = {}
+
+  def _AddMissingTranslation(self, lang, clique, is_error):
+    tl = self.fallback_translations_
+    if is_error:
+      tl = self.missing_translations_
+    id = clique.GetId()
+    if id not in tl:
+      tl[id] = {}
+    if lang not in tl[id]:
+      tl[id][lang] = 1
+
+  def HasMissingTranslations(self):
+    return len(self.missing_translations_) > 0
+
+  def MissingTranslationsReport(self):
+    '''Returns a string suitable for printing to report missing
+    and fallback translations to the user.
+    '''
+    def ReportTranslation(clique, langs):
+      text = clique.GetMessage().GetPresentableContent()
+      extract = text[0:40]
+      ellipsis = ''
+      if len(text) > 40:
+        ellipsis = '...'
+      langs_extract = langs[0:6]
+      describe_langs = ','.join(langs_extract)
+      if len(langs) > 6:
+        describe_langs += " and %d more" % (len(langs) - 6)
+      return "  %s \"%s%s\" %s" % (clique.GetId(), extract, ellipsis,
+                                   describe_langs)
+    lines = []
+    if len(self.fallback_translations_):
+      lines.append(
+        "WARNING: Fell back to English for the following translations:")
+      for (id, langs) in self.fallback_translations_.items():
+        lines.append(ReportTranslation(self.cliques_[id][0], langs.keys()))
+    if len(self.missing_translations_):
+      lines.append("ERROR: The following translations are MISSING:")
+      for (id, langs) in self.missing_translations_.items():
+        lines.append(ReportTranslation(self.cliques_[id][0], langs.keys()))
+    return '\n'.join(lines)
+
+  def MakeClique(self, message, translateable=True):
+    '''Create a new clique initialized  with a message.
+
+    Args:
+      message: tclib.Message()
+      translateable: True | False
+    '''
+    clique = MessageClique(self, message, translateable)
+
+    # Enable others to find this clique by its message ID
+    if message.GetId() in self.cliques_:
+      presentable_text = clique.GetMessage().GetPresentableContent()
+      for c in self.cliques_[message.GetId()]:
+        assert c.GetMessage().GetPresentableContent() == presentable_text
+      self.cliques_[message.GetId()].append(clique)
+    else:
+      self.cliques_[message.GetId()] = [clique]
+
+    return clique
+
+  def FindCliqueAndAddTranslation(self, translation, language):
+    '''Adds the specified translation to the clique with the source message
+    it is a translation of.
+
+    Args:
+      translation: tclib.Translation()
+      language: 'en' | 'fr' ...
+
+    Return:
+      True if the source message was found, otherwise false.
+    '''
+    if translation.GetId() in self.cliques_:
+      for clique in self.cliques_[translation.GetId()]:
+        clique.AddTranslation(translation, language)
+      return True
+    else:
+      return False
+
+  def BestClique(self, id):
+    '''Returns the "best" clique from a list of cliques.  All the cliques
+    must have the same ID.  The "best" clique is chosen in the following
+    order of preference:
+    - The first clique that has a non-ID-based description
+    - If no such clique found, one of the cliques with an ID-based description
+    - Otherwise an arbitrary clique
+    '''
+    clique_list = self.cliques_[id]
+    clique_to_ret = None
+    for clique in clique_list:
+      if not clique_to_ret:
+        clique_to_ret = clique
+
+      description = clique.GetMessage().GetDescription()
+      if description and len(description) > 0:
+        clique_to_ret = clique
+        if not description.startswith('ID:'):
+          break  # this is the preferred case so we exit right away
+    return clique_to_ret
+
+  def BestCliquePerId(self):
+    '''Iterates over the list of all cliques and returns the best clique for
+    each ID.  This will be the first clique with a source message that has a
+    non-empty description, or an arbitrary clique if none of them has a
+    description.
+    '''
+    for id in self.cliques_:
+      yield self.BestClique(id)
+
+  def BestCliqueByOriginalText(self, text, meaning):
+    '''Finds the "best" (as in BestClique()) clique that has original text
+    'text' and meaning 'meaning'.  Returns None if there is no such clique.
+    '''
+    # If needed, this can be optimized by maintaining a map of
+    # fingerprints of original text+meaning to cliques.
+    for c in self.BestCliquePerId():
+      msg = c.GetMessage()
+      if msg.GetRealContent() == text and msg.GetMeaning() == meaning:
+        return msg
+    return None
+
+  def AllMessageIds(self):
+    '''Returns a list of all defined message IDs.
+    '''
+    return self.cliques_.keys()
+
+  def AllCliques(self):
+    '''Iterates over all cliques.  Note that this can return multiple cliques
+    with the same ID.
+    '''
+    for cliques in self.cliques_.values():
+      for c in cliques:
+        yield c
+
+  def GenerateXtbParserCallback(self, lang, debug=False):
+    '''Creates a callback function as required by grit.xtb_reader.Parse().
+    This callback will create Translation objects for each message from
+    the XTB that exists in this uberclique, and add them as translations for
+    the relevant cliques.  The callback will add translations to the language
+    specified by 'lang'
+
+    Args:
+      lang: 'fr'
+      debug: True | False
+    '''
+    def Callback(id, structure):
+      if id not in self.cliques_:
+        if debug: print "Ignoring translation #%s" % id
+        return
+
+      if debug: print "Adding translation #%s" % id
+
+      # We fetch placeholder information from the original message (the XTB file
+      # only contains placeholder names).
+      original_msg = self.BestClique(id).GetMessage()
+
+      translation = tclib.Translation(id=id)
+      for is_ph,text in structure:
+        if not is_ph:
+          translation.AppendText(text)
+        else:
+          found_placeholder = False
+          for ph in original_msg.GetPlaceholders():
+            if ph.GetPresentation() == text:
+              translation.AppendPlaceholder(tclib.Placeholder(
+                ph.GetPresentation(), ph.GetOriginal(), ph.GetExample()))
+              found_placeholder = True
+              break
+          if not found_placeholder:
+            raise exception.MismatchingPlaceholders(
+              'Translation for message ID %s had <ph name="%s%/>, no match\n'
+              'in original message' % (id, text))
+      self.FindCliqueAndAddTranslation(translation, lang)
+    return Callback
+
+
+class CustomType(object):
+  '''A base class you should implement if you wish to specify a custom type
+  for a message clique (i.e. custom validation and optional modification of
+  translations).'''
+
+  def Validate(self, message):
+    '''Returns true if the message (a tclib.Message object) is valid,
+    otherwise false.
+    '''
+    raise NotImplementedError()
+
+  def ValidateAndModify(self, lang, translation):
+    '''Returns true if the translation (a tclib.Translation object) is valid,
+    otherwise false.  The language is also passed in.  This method may modify
+    the translation that is passed in, if it so wishes.
+    '''
+    raise NotImplementedError()
+
+  def ModifyTextPart(self, lang, text):
+    '''If you call ModifyEachTextPart, it will turn around and call this method
+    for each text part of the translation.  You should return the modified
+    version of the text, or just the original text to not change anything.
+    '''
+    raise NotImplementedError()
+
+  def ModifyEachTextPart(self, lang, translation):
+    '''Call this to easily modify one or more of the textual parts of a
+    translation.  It will call ModifyTextPart for each part of the
+    translation.
+    '''
+    contents = translation.GetContent()
+    for ix in range(len(contents)):
+      if (isinstance(contents[ix], types.StringTypes)):
+        contents[ix] = self.ModifyTextPart(lang, contents[ix])
+
+
+class OneOffCustomType(CustomType):
+  '''A very simple custom type that performs the validation expressed by
+  the input expression on all languages including the source language.
+  The expression can access the variables 'lang', 'msg' and 'text()' where 'lang'
+  is the language of 'msg', 'msg' is the message or translation being
+  validated and 'text()' returns the real contents of 'msg' (for shorthand).
+  '''
+  def __init__(self, expression):
+    self.expr = expression
+  def Validate(self, message):
+    return self.ValidateAndModify(MessageClique.source_language, message)
+  def ValidateAndModify(self, lang, msg):
+    def text():
+      return msg.GetRealContent()
+    return eval(self.expr, {},
+            {'lang' : lang,
+             'text' : text,
+             'msg' : msg,
+             })
+
+
+class MessageClique(object):
+  '''A message along with all of its translations.  Also code to bring
+  translations together with their original message.'''
+
+  # change this to the language code of Messages you add to cliques_.
+  # TODO(joi) Actually change this based on the <grit> node's source language
+  source_language = 'en'
+
+  # A constant translation we use when asked for a translation into the
+  # special language constants.CONSTANT_LANGUAGE.
+  CONSTANT_TRANSLATION = tclib.Translation(text='TTTTTT')
+
+  def __init__(self, uber_clique, message, translateable=True, custom_type=None):
+    '''Create a new clique initialized with just a message.
+
+    Args:
+      uber_clique: Our uber-clique (collection of cliques)
+      message: tclib.Message()
+      translateable: True | False
+      custom_type: instance of clique.CustomType interface
+    '''
+    # Our parent
+    self.uber_clique = uber_clique
+    # If not translateable, we only store the original message.
+    self.translateable = translateable
+    # A mapping of language identifiers to tclib.BaseMessage and its
+    # subclasses (i.e. tclib.Message and tclib.Translation).
+    self.clique = { MessageClique.source_language : message }
+    # A list of the "shortcut groups" this clique is
+    # part of.  Within any given shortcut group, no shortcut key (e.g. &J)
+    # must appear more than once in each language for all cliques that
+    # belong to the group.
+    self.shortcut_groups = []
+    # An instance of the CustomType interface, or None.  If this is set, it will
+    # be used to validate the original message and translations thereof, and
+    # will also get a chance to modify translations of the message.
+    self.SetCustomType(custom_type)
+
+  def GetMessage(self):
+    '''Retrieves the tclib.Message that is the source for this clique.'''
+    return self.clique[MessageClique.source_language]
+
+  def GetId(self):
+    '''Retrieves the message ID of the messages in this clique.'''
+    return self.GetMessage().GetId()
+
+  def IsTranslateable(self):
+    return self.translateable
+
+  def AddToShortcutGroup(self, group):
+    self.shortcut_groups.append(group)
+
+  def SetCustomType(self, custom_type):
+    '''Makes this clique use custom_type for validating messages and
+    translations, and optionally modifying translations.
+    '''
+    self.custom_type = custom_type
+    if custom_type and not custom_type.Validate(self.GetMessage()):
+      raise exception.InvalidMessage(self.GetMessage().GetRealContent())
+
+  def MessageForLanguage(self, lang, pseudo_if_no_match=True, fallback_to_english=False):
+    '''Returns the message/translation for the specified language, providing
+    a pseudotranslation if there is no available translation and a pseudo-
+    translation is requested.
+
+    The translation of any message whatsoever in the special language
+    'x_constant' is the message "TTTTTT".
+
+    Args:
+      lang: 'en'
+      pseudo_if_no_match: True
+      fallback_to_english: False
+
+    Return:
+      tclib.BaseMessage
+    '''
+    if not self.translateable:
+      return self.GetMessage()
+
+    if lang == constants.CONSTANT_LANGUAGE:
+      return self.CONSTANT_TRANSLATION
+
+    for msglang in self.clique.keys():
+      if lang == msglang:
+        return self.clique[msglang]
+
+    if lang == constants.FAKE_BIDI:
+      return pseudo_rtl.PseudoRTLMessage(self.GetMessage())
+
+    if fallback_to_english:
+      self.uber_clique._AddMissingTranslation(lang, self, is_error=False)
+      return self.GetMessage()
+
+    # If we're not supposed to generate pseudotranslations, we add an error
+    # report to a list of errors, then fail at a higher level, so that we
+    # get a list of all messages that are missing translations.
+    if not pseudo_if_no_match:
+      self.uber_clique._AddMissingTranslation(lang, self, is_error=True)
+
+    return pseudo.PseudoMessage(self.GetMessage())
+
+  def AllMessagesThatMatch(self, lang_re, include_pseudo = True):
+    '''Returns a map of all messages that match 'lang', including the pseudo
+    translation if requested.
+
+    Args:
+      lang_re: re.compile('fr|en')
+      include_pseudo: True
+
+    Return:
+      { 'en' : tclib.Message,
+        'fr' : tclib.Translation,
+        pseudo.PSEUDO_LANG : tclib.Translation }
+    '''
+    if not self.translateable:
+      return [self.GetMessage()]
+
+    matches = {}
+    for msglang in self.clique:
+      if lang_re.match(msglang):
+        matches[msglang] = self.clique[msglang]
+
+    if include_pseudo:
+      matches[pseudo.PSEUDO_LANG] = pseudo.PseudoMessage(self.GetMessage())
+
+    return matches
+
+  def AddTranslation(self, translation, language):
+    '''Add a translation to this clique.  The translation must have the same
+    ID as the message that is the source for this clique.
+
+    If this clique is not translateable, the function just returns.
+
+    Args:
+      translation: tclib.Translation()
+      language: 'en'
+
+    Throws:
+      grit.exception.InvalidTranslation if the translation you're trying to add
+      doesn't have the same message ID as the source message of this clique.
+    '''
+    if not self.translateable:
+      return
+    if translation.GetId() != self.GetId():
+      raise exception.InvalidTranslation(
+        'Msg ID %s, transl ID %s' % (self.GetId(), translation.GetId()))
+
+    assert not language in self.clique
+
+    # Because two messages can differ in the original content of their
+    # placeholders yet share the same ID (because they are otherwise the
+    # same), the translation we are getting may have different original
+    # content for placeholders than our message, yet it is still the right
+    # translation for our message (because it is for the same ID).  We must
+    # therefore fetch the original content of placeholders from our original
+    # English message.
+    #
+    # See grit.clique_unittest.MessageCliqueUnittest.testSemiIdenticalCliques
+    # for a concrete explanation of why this is necessary.
+
+    original = self.MessageForLanguage(self.source_language, False)
+    if len(original.GetPlaceholders()) != len(translation.GetPlaceholders()):
+      print ("ERROR: '%s' translation of message id %s does not match" %
+             (language, translation.GetId()))
+      assert False
+
+    transl_msg = tclib.Translation(id=self.GetId(),
+                                   text=translation.GetPresentableContent(),
+                                   placeholders=original.GetPlaceholders())
+
+    if self.custom_type and not self.custom_type.ValidateAndModify(language, transl_msg):
+      print "WARNING: %s translation failed validation: %s" % (
+        language, transl_msg.GetId())
+
+    self.clique[language] = transl_msg
+