1 files changed, 80 insertions, 0 deletions
diff --git a/powerline/lib/overrides.py b/powerline/lib/overrides.py
new file mode 100644
index 0000000..3257d98
--- /dev/null
+++ b/powerline/lib/overrides.py
@@ -0,0 +1,80 @@
+# vim:fileencoding=utf-8:noet
+from __future__ import (unicode_literals, division, absolute_import, print_function)
+
+import json
+
+from powerline.lib.dict import REMOVE_THIS_KEY
+
+
+def parse_value(s):
+	'''Convert string to Python object
+
+	Rules:
+
+	* Empty string means that corresponding key should be removed from the 
+	  dictionary.
+	* Strings that start with a minus, digit or with some character that starts 
+	  JSON collection or string object are parsed as JSON.
+	* JSON special values ``null``, ``true``, ``false`` (case matters) are 
+	  parsed  as JSON.
+	* All other values are considered to be raw strings.
+
+	:param str s: Parsed string.
+
+	:return: Python object.
+	'''
+	if not s:
+		return REMOVE_THIS_KEY
+	elif s[0] in '"{[0123456789-' or s in ('null', 'true', 'false'):
+		return json.loads(s)
+	else:
+		return s
+
+
+def keyvaluesplit(s):
+	'''Split K1.K2=VAL into K1.K2 and parsed VAL
+	'''
+	if '=' not in s:
+		raise TypeError('Option must look like option=json_value')
+	if s[0] == '_':
+		raise ValueError('Option names must not start with `_\'')
+	idx = s.index('=')
+	o = s[:idx]
+	val = parse_value(s[idx + 1:])
+	return (o, val)
+
+
+def parsedotval(s):
+	'''Parse K1.K2=VAL into {"K1":{"K2":VAL}}
+
+	``VAL`` is processed according to rules defined in :py:func:`parse_value`.
+	'''
+	if type(s) is tuple:
+		o, val = s
+		val = parse_value(val)
+	else:
+		o, val = keyvaluesplit(s)
+
+	keys = o.split('.')
+	if len(keys) > 1:
+		r = (keys[0], {})
+		rcur = r[1]
+		for key in keys[1:-1]:
+			rcur[key] = {}
+			rcur = rcur[key]
+		rcur[keys[-1]] = val
+		return r
+	else:
+		return (o, val)
+
+
+def parse_override_var(s):
+	'''Parse a semicolon-separated list of strings into a sequence of values
+
+	Emits the same items in sequence as :py:func:`parsedotval` does.
+	'''
+	return (
+		parsedotval(item)
+		for item in s.split(';')
+		if item
+	)