Use &encoding as powerline encoding in Vim

Among other benefits (i.e. correct fall back to ascii theme when Vim uses
non-unicode encoding) this should also fix travis tests: apparently travis is
not setting LANG or similar environment variables to some unicode locale, so
tests are failing.

powerline/__init__.py

@@ -225,7 +225,7 @@ def create_logger(common_config):
 	return logger
 
 
-def finish_common_config(common_config):
+def finish_common_config(encoding, common_config):
 	'''Add default values to common config and expand ~ in paths
 
 	:param dict common_config:
@@ -235,7 +235,7 @@ def finish_common_config(common_config):
 		Copy of common configuration with all configuration keys and expanded 
 		paths.
 	'''
-	encoding = getpreferredencoding().lower()
+	encoding = encoding.lower()
 	if encoding.startswith('utf') or encoding.startswith('ucs'):
 		default_top_theme = 'powerline'
 	else:
@@ -407,6 +407,12 @@ class Powerline(object):
 		self.setup_kwargs = {}
 		self.imported_modules = set()
 
+	get_encoding = staticmethod(getpreferredencoding)
+	'''Get encoding used by the current application
+
+	Usually returns encoding of the current locale.
+	'''
+
 	def create_renderer(self, load_main=False, load_colors=False, load_colorscheme=False, load_theme=False):
 		'''(Re)create renderer object. Can be used after Powerline object was 
 		successfully initialized. If any of the below parameters except 
@@ -431,7 +437,7 @@ class Powerline(object):
 		if load_main:
 			self._purge_configs('main')
 			config = self.load_main_config()
-			self.common_config = finish_common_config(config['common'])
+			self.common_config = finish_common_config(self.get_encoding(), config['common'])
 			if self.common_config != self.prev_common_config:
 				common_config_differs = True
 

powerline/bindings/config.py

@@ -6,6 +6,8 @@ import os
 import re
 import sys
 
+from locale import getpreferredencoding
+
 from powerline.config import POWERLINE_ROOT, TMUX_CONFIG_DIRECTORY
 from powerline.lib.config import ConfigLoader
 from powerline import generate_config_finder, load_config, create_logger, PowerlineLogger, finish_common_config
@@ -83,7 +85,7 @@ def get_main_config(args):
 
 def create_powerline_logger(args):
 	config = get_main_config(args)
-	common_config = finish_common_config(config['common'])
+	common_config = finish_common_config(getpreferredencoding(), config['common'])
 	logger = create_logger(common_config)
 	return PowerlineLogger(use_daemon_threads=True, logger=logger, ext='config')
 

powerline/vim.py

@@ -3,11 +3,14 @@
 from __future__ import absolute_import
 
 import sys
+
+from itertools import count
+
+import vim
+
 from powerline.bindings.vim import vim_get_func, vim_getvar
 from powerline import Powerline, FailedUnicode
 from powerline.lib import mergedicts
-import vim
-from itertools import count
 
 if not hasattr(vim, 'bindeval'):
 	import json
@@ -71,6 +74,10 @@ class VimPowerline(Powerline):
 			self.setup_kwargs.setdefault('_local_themes', []).append((key, config))
 			return True
 
+	@staticmethod
+	def get_encoding():
+		return vim.eval('&encoding')
+
 	def load_main_config(self):
 		return _override_from(super(VimPowerline, self).load_main_config(), 'powerline_config_overrides')
 

tests/test_local_overrides.vim

@@ -1,4 +1,5 @@
 #!/usr/bin/vim -S
+set encoding=utf-8
 let g:powerline_config_path = expand('<sfile>:p:h:h') . '/powerline/config_files'
 let g:powerline_config_overrides = {'common': {'default_top_theme': 'ascii'}}
 let g:powerline_theme_overrides__default = {'segment_data': {'line_current_symbol': {'contents': 'LN '}, 'branch': {'before': 'B '}}}

tests/test_plugin_file.vim

@@ -1,5 +1,5 @@
 #!/usr/bin/vim -S
-set nocompatible
+set encoding=utf-8
 tabedit abc
 tabedit def
 try

tests/test_tabline.vim

@@ -1,4 +1,5 @@
 #!/usr/bin/vim -S
+set encoding=utf-8
 source powerline/bindings/vim/plugin/powerline.vim
 edit abc
 tabedit def

tests/vim.py

@@ -9,6 +9,7 @@ options = {
 	'paste': 0,
 	'ambiwidth': 'single',
 	'columns': 80,
+	'encoding': 'utf-8',
 }
 _last_bufnr = 0
 _highlights = {}