Split up the utf encoding handling into a separate file.

matrix/utf.py

@@ -0,0 +1,91 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+import sys
+
+# pylint: disable=redefined-builtin
+from builtins import bytes, str
+from collections import Mapping, Iterable
+from functools import wraps
+
+
+# These functions were written by Trygve Aaberge for wee-slack and are under a
+# MIT License.
+# More info can be found in the wee-slack repository under the commit:
+# 5e1c7e593d70972afb9a55f29d13adaf145d0166, the repository can be found at:
+# https://github.com/wee-slack/wee-slack
+
+
+class WeechatWrapper(object):
+    def __init__(self, wrapped_class):
+        self.wrapped_class = wrapped_class
+
+    # Helper method used to encode/decode method calls.
+    def wrap_for_utf8(self, method):
+        def hooked(*args, **kwargs):
+            result = method(*encode_to_utf8(args), **encode_to_utf8(kwargs))
+            # Prevent wrapped_class from becoming unwrapped
+            if result == self.wrapped_class:
+                return self
+            return decode_from_utf8(result)
+        return hooked
+
+    # Encode and decode everything sent to/received from weechat. We use the
+    # unicode type internally in wee-slack, but has to send utf8 to weechat.
+    def __getattr__(self, attr):
+        orig_attr = self.wrapped_class.__getattribute__(attr)
+        if callable(orig_attr):
+            return self.wrap_for_utf8(orig_attr)
+        return decode_from_utf8(orig_attr)
+
+    # Ensure all lines sent to weechat specify a prefix. For lines after the
+    # first, we want to disable the prefix, which is done by specifying a
+    # space.
+    def prnt_date_tags(self, buffer, date, tags, message):
+        message = message.replace("\n", "\n \t")
+        return self.wrap_for_utf8(self.wrapped_class.prnt_date_tags)(
+            buffer,
+            date,
+            tags,
+            message
+        )
+
+
+def utf8_decode(function):
+    """
+    Decode all arguments from byte strings to unicode strings. Use this for
+    functions called from outside of this script, e.g. callbacks from weechat.
+    """
+    @wraps(function)
+    def wrapper(*args, **kwargs):
+
+        # Don't do anything if we're python 3
+        if sys.hexversion >= 0x3000000:
+            return function(*args, **kwargs)
+
+        return function(*decode_from_utf8(args), **decode_from_utf8(kwargs))
+    return wrapper
+
+
+def decode_from_utf8(data):
+    if isinstance(data, bytes):
+        return data.decode('utf-8')
+    if isinstance(data, str):
+        return data
+    elif isinstance(data, Mapping):
+        return type(data)(map(decode_from_utf8, data.items()))
+    elif isinstance(data, Iterable):
+        return type(data)(map(decode_from_utf8, data))
+    return data
+
+
+def encode_to_utf8(data):
+    if isinstance(data, str):
+        return data.encode('utf-8')
+    if isinstance(data, bytes):
+        return data
+    elif isinstance(data, Mapping):
+        return type(data)(map(encode_to_utf8, data.items()))
+    elif isinstance(data, Iterable):
+        return type(data)(map(encode_to_utf8, data))
+    return data