path: root/src/engine/SCons/Tool/xgettext.py

""" xgettext tool 

Tool specific initialization of `xgettext` tool.
"""

# __COPYRIGHT__
# 
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
# 
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"

#############################################################################
class _CmdRunner(object):
  """ Callabe object, which runs shell command storing its stdout and stderr to
  variables. It also provides `strfunction()` method, which shall be used by
  scons Action objects to print command string. """

  def __init__( self, command, commandstr = None):
    self.out = None
    self.err = None
    self.status = None
    self.command = command
    self.commandstr = commandstr

  def __call__(self, target, source, env): 
    import SCons.Action
    import subprocess
    import os
    import sys
    kw = { 
      'stdin'  : 'devnull',
      'stdout' : subprocess.PIPE,
      'stderr' : subprocess.PIPE,
      'universal_newlines' : True,
      'shell'  : True
    }
    command = env.subst(self.command, target = target, source = source)
    proc = SCons.Action._subproc(env, command, **kw)
    self.out, self.err = proc.communicate()
    self.status = proc.wait()
    if self.err: sys.stderr.write(unicode(self.err))
    return self.status

  def strfunction(self, target, source, env):
    import os
    comstr = self.commandstr
    if env.subst(comstr, target = target, source = source) == "":
      comstr = self.command
    s = env.subst(comstr, target = target, source = source)
    return s
#############################################################################

#############################################################################
def _update_pot_file(target, source, env):
  """ Action function for `POTUpdate` builder """
  import re
  import os
  import SCons.Action
  nop = lambda target, source, env : 0

  # Save scons cwd and os cwd (NOTE: they may be different. After the job, we
  # revert ech one to its original state).
  save_cwd = env.fs.getcwd()
  save_os_cwd = os.getcwd()
  chdir = target[0].dir
  chdir_str = repr(chdir.get_abspath())
  # Print chdir message (employ SCons.Action.Action for that. It knows better
  # than me how to to this correctly).
  env.Execute(SCons.Action.Action(nop, "Entering " + chdir_str))
  # Go to target's directory and do our job
  env.fs.chdir(chdir, 1) # Go into target's directory
  try:
    cmd = _CmdRunner('$XGETTEXTCOM', '$XGETTEXTCOMSTR')
    action = SCons.Action.Action(cmd, strfunction=cmd.strfunction)
    status = action([ target[0] ], source, env)
  except:
    # Something went wrong.
    env.Execute(SCons.Action.Action(nop, "Leaving " + chdir_str))
    # Revert working dirs to previous state and re-throw exception.
    env.fs.chdir(save_cwd, 0)
    os.chdir(save_os_cwd)
    raise
  # Print chdir message.
  env.Execute(SCons.Action.Action(nop, "Leaving " + chdir_str))
  # Revert working dirs to previous state.
  env.fs.chdir(save_cwd, 0)
  os.chdir(save_os_cwd)
  # If the command was not successfull, return error code.
  if status: return status
 
  new_content = cmd.out
 
  if not new_content:
    # When xgettext finds no internationalized messages, no *.pot is created
    # (because we don't want to bother translators with empty POT files).
    needs_update = False
    explain = "no internationalized messages encountered"
  else:
    if target[0].exists():
      # If the file already exists, it's left unaltered unless its messages
      # are outdated (w.r.t. to these recovered by xgettext from sources).
      old_content = target[0].get_text_contents()
      re_cdate = re.compile(r'^"POT-Creation-Date: .*"$[\r\n]?', re.M)
      old_content_nocdate = re.sub(re_cdate,"",old_content)
      new_content_nocdate = re.sub(re_cdate,"",new_content)
      if(old_content_nocdate == new_content_nocdate):
        # Messages are up-to-date
        needs_update = False
        explain = "messages in file found to be up-to-date"
      else:
        # Messages are outdated
        needs_update = True
        explain = "messages in file were outdated"
    else:
      # No POT file found, create new one
      needs_update = True
      explain = "new file"
  if needs_update:
    # Print message employing SCons.Action.Action for that.
    msg = "Writting " + repr(str(target[0])) + " (" + explain + ")"
    env.Execute(SCons.Action.Action(nop, msg))
    f = open(str(target[0]),"w")
    f.write(new_content)
    f.close()
    return 0
  else:
    # Print message employing SCons.Action.Action for that.
    msg = "Not writting " + repr(str(target[0])) + " (" + explain + ")"
    env.Execute(SCons.Action.Action(nop, msg))
    return 0 
#############################################################################

#############################################################################
from SCons.Builder import BuilderBase
#############################################################################
class _POTBuilder(BuilderBase):
  def _execute(self, env, target, source, *args):
    if not target:
      if env.has_key('POTDOMAIN') and env['POTDOMAIN']:
        domain = env['POTDOMAIN']
      else:
        domain = 'messages'
      target = [ domain ]
    return BuilderBase._execute(self, env, target, source, *args)
#############################################################################

#############################################################################
def _scan_xgettext_from_files(target, source, env, files = None, path = None):
  """ Parses `POTFILES.in`-like file and returns list of extracted file names.
  """
  import re
  import SCons.Util
  import SCons.Node.FS

  if files is None:
    return 0
  if not SCons.Util.is_List(files):
    files = [ files ]

  if path is None:
    if env.has_key('XGETTEXTPATH'):
      path = env['XGETTEXTPATH']
    else:
      path = []
  if not SCons.Util.is_List(path):
    path = [ path ]

  path = SCons.Util.flatten(path)

  dirs = ()
  for p in path:
    if not isinstance(p, SCons.Node.FS.Base):
      if SCons.Util.is_String(p):
        p = env.subst(p, source = source, target = target)
      p = env.arg2nodes(p, env.fs.Dir)
    dirs += tuple(p)
  # cwd is the default search path (when no path is defined by user)
  if not dirs:
    dirs = (env.fs.getcwd(),)

  # Parse 'POTFILE.in' files.
  re_comment = re.compile(r'^#[^\n\r]*$\r?\n?', re.M)
  re_emptyln = re.compile(r'^[ \t\r]*$\r?\n?', re.M)
  re_trailws = re.compile(r'[ \t\r]+$')
  for f in files:
    # Find files in search path $XGETTEXTPATH
    if isinstance(f, SCons.Node.FS.Base) and f.rexists():
      contents = f.get_text_contents()
      contents = re_comment.sub("", contents)
      contents = re_emptyln.sub("", contents)
      contents = re_trailws.sub("", contents)
      depnames = contents.splitlines()
      for depname in depnames: 
        depfile = SCons.Node.FS.find_file(depname, dirs)
        if not depfile:
          depfile = env.arg2nodes(depname, dirs[0].File)
        env.Depends(target, depfile)
  return 0
#############################################################################

#############################################################################
def _pot_update_emitter(target, source, env):
  """ Emitter function for `POTUpdate` builder """
  from SCons.Tool.GettextCommon import _POTargetFactory
  import SCons.Util
  import SCons.Node.FS

  if env.has_key('XGETTEXTFROM'): 
    xfrom = env['XGETTEXTFROM']
  else:
    return target, source
  if not SCons.Util.is_List(xfrom):
    xfrom = [ xfrom ]

  xfrom = SCons.Util.flatten(xfrom)
  
  # Prepare list of 'POTFILE.in' files.
  files = []
  for xf in xfrom:
    if not isinstance(xf, SCons.Node.FS.Base):
      if SCons.Util.is_String(xf):
        # Interpolate variables in strings 
        xf = env.subst(xf, source = source, target = target)
      xf = env.arg2nodes(xf)
    files.extend(xf)
  if files:
    env.Depends(target, files)
    _scan_xgettext_from_files(target, source, env, files)
  return target, source
#############################################################################

#############################################################################
from SCons.Environment import _null
#############################################################################
def _POTUpdateBuilderWrapper(env, target=None, source=_null, **kw):
  return env._POTUpdateBuilder(target, source, **kw)
#############################################################################

#############################################################################
def _POTUpdateBuilder(env, **kw):
  """ Creates `POTUpdate` builder object """
  import SCons.Action
  from SCons.Tool.GettextCommon import _POTargetFactory
  kw['action'] = SCons.Action.Action(_update_pot_file, None)
  kw['suffix'] = '$POTSUFFIX'
  kw['target_factory'] = _POTargetFactory(env, alias='$POTUPDATE_ALIAS').File
  kw['emitter'] = _pot_update_emitter
  return _POTBuilder(**kw)
#############################################################################

#############################################################################
def generate(env,**kw):
  """ Generate `xgettext` tool """
  import SCons.Util
  from SCons.Tool.GettextCommon import RPaths, _detect_xgettext

  try:
    env['XGETTEXT'] = _detect_xgettext(env)
  except:
    env['XGETTEXT'] = 'xgettext' 
  # NOTE: sources="$SOURCES" would work as well. However, we use following
  # construction to convert absolute paths provided by scons onto paths
  # relative to current working dir. Note, that scons expands $SOURCE(S) to
  # absolute paths for sources $SOURCE(s) outside of current subtree (e.g. in
  # "../"). With source=$SOURCE these absolute paths would be written to the
  # resultant *.pot file (and its derived *.po files) as references to lines in
  # source code (e.g. referring lines in *.c files). Such references would be
  # correct (e.g. in poedit) only on machine on which *.pot was generated and
  # would be of no use on other hosts (having a copy of source code located
  # in different place in filesystem).
  sources = '$( ${_concat( "", SOURCES, "", __env__, XgettextRPaths, TARGET' \
    + ', SOURCES)} $)'

  # NOTE: the output from $XGETTEXTCOM command must go to stdout, not to a file.
  # This is required by the POTUpdate builder's action.
  xgettextcom = '$XGETTEXT $XGETTEXTFLAGS $_XGETTEXTPATHFLAGS' \
    + ' $_XGETTEXTFROMFLAGS -o - ' + sources

  xgettextpathflags = '$( ${_concat( XGETTEXTPATHPREFIX, XGETTEXTPATH' \
    + ', XGETTEXTPATHSUFFIX, __env__, RDirs, TARGET, SOURCES)} $)'
  xgettextfromflags = '$( ${_concat( XGETTEXTFROMPREFIX, XGETTEXTFROM' \
    + ', XGETTEXTFROMSUFFIX, __env__, target=TARGET, source=SOURCES)} $)'

  env.SetDefault(
    _XGETTEXTDOMAIN     = '${TARGET.filebase}',
    XGETTEXTFLAGS       = [ ],
    XGETTEXTCOM         = xgettextcom,
    XGETTEXTCOMSTR      = '',
    XGETTEXTPATH        = [ ],
    XGETTEXTPATHPREFIX   = '-D',
    XGETTEXTPATHSUFFIX   = '',
    XGETTEXTFROM        = None,
    XGETTEXTFROMPREFIX   = '-f',
    XGETTEXTFROMSUFFIX   = '',
   _XGETTEXTPATHFLAGS    = xgettextpathflags,
   _XGETTEXTFROMFLAGS   = xgettextfromflags,
    POTSUFFIX           =  ['.pot'],
    POTUPDATE_ALIAS     = 'pot-update',
    XgettextRPaths      = RPaths(env)
  )
  env.Append( BUILDERS = {
    '_POTUpdateBuilder' : _POTUpdateBuilder(env)
  } )
  env.AddMethod(_POTUpdateBuilderWrapper, 'POTUpdate')
  env.AlwaysBuild(env.Alias('$POTUPDATE_ALIAS'))
#############################################################################

#############################################################################
def exists(env):
  """ Check, whether the tool exists """
  from SCons.Tool.GettextCommon import _xgettext_exists
  try:
    return _xgettext_exists(env)
  except:
    return False
#############################################################################

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