prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  Add traits and variants support in l20nfile
  L20n traits allow storing value variants and additional information for a unit. We need to add such support when parsing `.ftl` and convert resources.
  
  ```
  file-menu =
      [xul/label]     File
      [xul/accesskey] F
  ```
  
  
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `translate/storage/l20n.py`
  Content:
  ```
  1 # -*- coding: utf-8 -*-
  2 #
  3 # Copyright 2016 Zuza Software Foundation
  4 #
  5 # This file is part of translate.
  6 #
  7 # translate is free software; you can redistribute it and/or modify
  8 # it under the terms of the GNU General Public License as published by
  9 # the Free Software Foundation; either version 2 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # translate is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program; if not, see <http://www.gnu.org/licenses/>.
  19 
  20 from __future__ import absolute_import
  21 
  22 from codecs import iterencode
  23 
  24 from l20n.format.parser import FTLParser as L20nParser
  25 from l20n.format.serializer import FTLSerializer as L20nSerializer
  26 
  27 from translate.storage import base
  28 
  29 
  30 class l20nunit(base.TranslationUnit):
  31     """Single L20n Entity"""
  32 
  33     def __init__(self, source='', id='', comment=''):
  34         super(l20nunit, self).__init__(source)
  35         self.id = id
  36         self.value = source
  37         self.comment = comment
  38 
  39     # Note that source and target are equivalent for monolingual units
  40     def getsource(self):
  41         return self.value
  42 
  43     def setsource(self, source):
  44         self.value = source
  45 
  46     source = property(getsource, setsource)
  47 
  48     def gettarget(self):
  49         return self.value
  50 
  51     def settarget(self, target):
  52         self.value = target
  53 
  54     target = property(gettarget, settarget)
  55 
  56     def getid(self):
  57         return self.id
  58 
  59     def setid(self, new_id):
  60         self.id = new_id
  61 
  62     def getoutput(self):
  63         return u"%s = %s\n" % (self.id, self.value)
  64 
  65 
  66 class l20nfile(base.TranslationStore):
  67     UnitClass = l20nunit
  68     encoding = 'utf8'
  69 
  70     def __init__(self, inputfile=None):
  71         super(l20nfile, self).__init__(unitclass=self.UnitClass)
  72         self.filename = getattr(inputfile, 'name', '')
  73         if inputfile is not None:
  74             l20nsrc = inputfile.read()
  75             self.parse(l20nsrc)
  76             self.makeindex()
  77 
  78     def parse(self, l20nsrc):
  79         text, encoding = self.detect_encoding(
  80             l20nsrc, default_encodings=[self.encoding])
  81         if not text:
  82             raise IOError("Cannot detect encoding for %s." % (self.filename or
  83                                                               "given string"))
  84         l20nsrc = text
  85 
  86         parser = L20nParser()
  87         ast, errors = parser.parseResource(l20nsrc)
  88 
  89         for entry in ast['body']:
  90             if entry['type'] == 'Entity':
  91                 translation = L20nSerializer().dumpPattern(entry['value'])
  92                 comment = ''
  93                 if entry['comment']:
  94                     comment = entry['comment']['content']
  95 
  96                 newl20n = l20nunit(
  97                     source=translation,
  98                     id=entry['id']['name'],
  99                     comment=comment
  100                 )
  101                 self.addunit(newl20n)
  102 
  103     def serialize(self, out):
  104         """Write the units back to file."""
  105         # Thanks to iterencode, a possible BOM is written only once
  106         for chunk in iterencode((unit.getoutput() for unit in self.units), self.encoding):
  107             out.write(chunk)
  108
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/translate/storage/l20n.py b/translate/storage/l20n.py
  --- a/translate/storage/l20n.py
  +++ b/translate/storage/l20n.py
  @@ -27,6 +27,17 @@
   from translate.storage import base
   
   
  +def dump_l20n_entity_value(entity):
  +    serializer = L20nSerializer()
  +    value = serializer.dumpPattern(entity['value'])
  +
  +    if len(entity['traits']):
  +        traits = serializer.dumpMembers(entity['traits'], 2)
  +        return u'{}\n{}'.format(value, traits)
  +
  +    return value
  +
  +
   class l20nunit(base.TranslationUnit):
       """Single L20n Entity"""
   
  @@ -75,6 +86,19 @@
               self.parse(l20nsrc)
               self.makeindex()
   
  +    def parse_entity(self, entity):
  +        translation = dump_l20n_entity_value(entity)
  +        comment = ''
  +        if entity['comment']:
  +            comment = entity['comment']['content']
  +
  +        newl20n = l20nunit(
  +            source=translation,
  +            id=entity['id']['name'],
  +            comment=comment
  +        )
  +        self.addunit(newl20n)
  +
       def parse(self, l20nsrc):
           text, encoding = self.detect_encoding(
               l20nsrc, default_encodings=[self.encoding])
  @@ -88,17 +112,7 @@
   
           for entry in ast['body']:
               if entry['type'] == 'Entity':
  -                translation = L20nSerializer().dumpPattern(entry['value'])
  -                comment = ''
  -                if entry['comment']:
  -                    comment = entry['comment']['content']
  -
  -                newl20n = l20nunit(
  -                    source=translation,
  -                    id=entry['id']['name'],
  -                    comment=comment
  -                )
  -                self.addunit(newl20n)
  +                self.parse_entity(entry)
   
       def serialize(self, out):
           """Write the units back to file."""
  
verification_info: {"golden_diff": "diff --git a/translate/storage/l20n.py b/translate/storage/l20n.py\n--- a/translate/storage/l20n.py\n+++ b/translate/storage/l20n.py\n@@ -27,6 +27,17 @@\n from translate.storage import base\n \n \n+def dump_l20n_entity_value(entity):\n+    serializer = L20nSerializer()\n+    value = serializer.dumpPattern(entity['value'])\n+\n+    if len(entity['traits']):\n+        traits = serializer.dumpMembers(entity['traits'], 2)\n+        return u'{}\\n{}'.format(value, traits)\n+\n+    return value\n+\n+\n class l20nunit(base.TranslationUnit):\n     \"\"\"Single L20n Entity\"\"\"\n \n@@ -75,6 +86,19 @@\n             self.parse(l20nsrc)\n             self.makeindex()\n \n+    def parse_entity(self, entity):\n+        translation = dump_l20n_entity_value(entity)\n+        comment = ''\n+        if entity['comment']:\n+            comment = entity['comment']['content']\n+\n+        newl20n = l20nunit(\n+            source=translation,\n+            id=entity['id']['name'],\n+            comment=comment\n+        )\n+        self.addunit(newl20n)\n+\n     def parse(self, l20nsrc):\n         text, encoding = self.detect_encoding(\n             l20nsrc, default_encodings=[self.encoding])\n@@ -88,17 +112,7 @@\n \n         for entry in ast['body']:\n             if entry['type'] == 'Entity':\n-                translation = L20nSerializer().dumpPattern(entry['value'])\n-                comment = ''\n-                if entry['comment']:\n-                    comment = entry['comment']['content']\n-\n-                newl20n = l20nunit(\n-                    source=translation,\n-                    id=entry['id']['name'],\n-                    comment=comment\n-                )\n-                self.addunit(newl20n)\n+                self.parse_entity(entry)\n \n     def serialize(self, out):\n         \"\"\"Write the units back to file.\"\"\"\n", "issue": "Add traits and variants support in l20nfile\nL20n traits allow storing value variants and additional information for a unit. We need to add such support when parsing `.ftl` and convert resources.\r\n\r\n```\r\nfile-menu =\r\n    [xul/label]     File\r\n    [xul/accesskey] F\r\n```\r\n\r\n\n", "before_files": [{"content": "# -*- coding: utf-8 -*-\n#\n# Copyright 2016 Zuza Software Foundation\n#\n# This file is part of translate.\n#\n# translate is free software; you can redistribute it and/or modify\n# it under the terms of the GNU General Public License as published by\n# the Free Software Foundation; either version 2 of the License, or\n# (at your option) any later version.\n#\n# translate is distributed in the hope that it will be useful,\n# but WITHOUT ANY WARRANTY; without even the implied warranty of\n# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n# GNU General Public License for more details.\n#\n# You should have received a copy of the GNU General Public License\n# along with this program; if not, see <http://www.gnu.org/licenses/>.\n\nfrom __future__ import absolute_import\n\nfrom codecs import iterencode\n\nfrom l20n.format.parser import FTLParser as L20nParser\nfrom l20n.format.serializer import FTLSerializer as L20nSerializer\n\nfrom translate.storage import base\n\n\nclass l20nunit(base.TranslationUnit):\n    \"\"\"Single L20n Entity\"\"\"\n\n    def __init__(self, source='', id='', comment=''):\n        super(l20nunit, self).__init__(source)\n        self.id = id\n        self.value = source\n        self.comment = comment\n\n    # Note that source and target are equivalent for monolingual units\n    def getsource(self):\n        return self.value\n\n    def setsource(self, source):\n        self.value = source\n\n    source = property(getsource, setsource)\n\n    def gettarget(self):\n        return self.value\n\n    def settarget(self, target):\n        self.value = target\n\n    target = property(gettarget, settarget)\n\n    def getid(self):\n        return self.id\n\n    def setid(self, new_id):\n        self.id = new_id\n\n    def getoutput(self):\n        return u\"%s = %s\\n\" % (self.id, self.value)\n\n\nclass l20nfile(base.TranslationStore):\n    UnitClass = l20nunit\n    encoding = 'utf8'\n\n    def __init__(self, inputfile=None):\n        super(l20nfile, self).__init__(unitclass=self.UnitClass)\n        self.filename = getattr(inputfile, 'name', '')\n        if inputfile is not None:\n            l20nsrc = inputfile.read()\n            self.parse(l20nsrc)\n            self.makeindex()\n\n    def parse(self, l20nsrc):\n        text, encoding = self.detect_encoding(\n            l20nsrc, default_encodings=[self.encoding])\n        if not text:\n            raise IOError(\"Cannot detect encoding for %s.\" % (self.filename or\n                                                              \"given string\"))\n        l20nsrc = text\n\n        parser = L20nParser()\n        ast, errors = parser.parseResource(l20nsrc)\n\n        for entry in ast['body']:\n            if entry['type'] == 'Entity':\n                translation = L20nSerializer().dumpPattern(entry['value'])\n                comment = ''\n                if entry['comment']:\n                    comment = entry['comment']['content']\n\n                newl20n = l20nunit(\n                    source=translation,\n                    id=entry['id']['name'],\n                    comment=comment\n                )\n                self.addunit(newl20n)\n\n    def serialize(self, out):\n        \"\"\"Write the units back to file.\"\"\"\n        # Thanks to iterencode, a possible BOM is written only once\n        for chunk in iterencode((unit.getoutput() for unit in self.units), self.encoding):\n            out.write(chunk)\n", "path": "translate/storage/l20n.py"}], "after_files": [{"content": "# -*- coding: utf-8 -*-\n#\n# Copyright 2016 Zuza Software Foundation\n#\n# This file is part of translate.\n#\n# translate is free software; you can redistribute it and/or modify\n# it under the terms of the GNU General Public License as published by\n# the Free Software Foundation; either version 2 of the License, or\n# (at your option) any later version.\n#\n# translate is distributed in the hope that it will be useful,\n# but WITHOUT ANY WARRANTY; without even the implied warranty of\n# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n# GNU General Public License for more details.\n#\n# You should have received a copy of the GNU General Public License\n# along with this program; if not, see <http://www.gnu.org/licenses/>.\n\nfrom __future__ import absolute_import\n\nfrom codecs import iterencode\n\nfrom l20n.format.parser import FTLParser as L20nParser\nfrom l20n.format.serializer import FTLSerializer as L20nSerializer\n\nfrom translate.storage import base\n\n\ndef dump_l20n_entity_value(entity):\n    serializer = L20nSerializer()\n    value = serializer.dumpPattern(entity['value'])\n\n    if len(entity['traits']):\n        traits = serializer.dumpMembers(entity['traits'], 2)\n        return u'{}\\n{}'.format(value, traits)\n\n    return value\n\n\nclass l20nunit(base.TranslationUnit):\n    \"\"\"Single L20n Entity\"\"\"\n\n    def __init__(self, source='', id='', comment=''):\n        super(l20nunit, self).__init__(source)\n        self.id = id\n        self.value = source\n        self.comment = comment\n\n    # Note that source and target are equivalent for monolingual units\n    def getsource(self):\n        return self.value\n\n    def setsource(self, source):\n        self.value = source\n\n    source = property(getsource, setsource)\n\n    def gettarget(self):\n        return self.value\n\n    def settarget(self, target):\n        self.value = target\n\n    target = property(gettarget, settarget)\n\n    def getid(self):\n        return self.id\n\n    def setid(self, new_id):\n        self.id = new_id\n\n    def getoutput(self):\n        return u\"%s = %s\\n\" % (self.id, self.value)\n\n\nclass l20nfile(base.TranslationStore):\n    UnitClass = l20nunit\n    encoding = 'utf8'\n\n    def __init__(self, inputfile=None):\n        super(l20nfile, self).__init__(unitclass=self.UnitClass)\n        self.filename = getattr(inputfile, 'name', '')\n        if inputfile is not None:\n            l20nsrc = inputfile.read()\n            self.parse(l20nsrc)\n            self.makeindex()\n\n    def parse_entity(self, entity):\n        translation = dump_l20n_entity_value(entity)\n        comment = ''\n        if entity['comment']:\n            comment = entity['comment']['content']\n\n        newl20n = l20nunit(\n            source=translation,\n            id=entity['id']['name'],\n            comment=comment\n        )\n        self.addunit(newl20n)\n\n    def parse(self, l20nsrc):\n        text, encoding = self.detect_encoding(\n            l20nsrc, default_encodings=[self.encoding])\n        if not text:\n            raise IOError(\"Cannot detect encoding for %s.\" % (self.filename or\n                                                              \"given string\"))\n        l20nsrc = text\n\n        parser = L20nParser()\n        ast, errors = parser.parseResource(l20nsrc)\n\n        for entry in ast['body']:\n            if entry['type'] == 'Entity':\n                self.parse_entity(entry)\n\n    def serialize(self, out):\n        \"\"\"Write the units back to file.\"\"\"\n        # Thanks to iterencode, a possible BOM is written only once\n        for chunk in iterencode((unit.getoutput() for unit in self.units), self.encoding):\n            out.write(chunk)\n", "path": "translate/storage/l20n.py"}]}