Python: Recognise walrus operator (#3126)

components/prism-python.js

@@ -55,7 +55,7 @@ Prism.languages.python = {
 	'builtin': /\b(?:__import__|abs|all|any|apply|ascii|basestring|bin|bool|buffer|bytearray|bytes|callable|chr|classmethod|cmp|coerce|compile|complex|delattr|dict|dir|divmod|enumerate|eval|execfile|file|filter|float|format|frozenset|getattr|globals|hasattr|hash|help|hex|id|input|int|intern|isinstance|issubclass|iter|len|list|locals|long|map|max|memoryview|min|next|object|oct|open|ord|pow|property|range|raw_input|reduce|reload|repr|reversed|round|set|setattr|slice|sorted|staticmethod|str|sum|super|tuple|type|unichr|unicode|vars|xrange|zip)\b/,
 	'boolean': /\b(?:False|None|True)\b/,
 	'number': /\b0(?:b(?:_?[01])+|o(?:_?[0-7])+|x(?:_?[a-f0-9])+)\b|(?:\b\d+(?:_\d+)*(?:\.(?:\d+(?:_\d+)*)?)?|\B\.\d+(?:_\d+)*)(?:e[+-]?\d+(?:_\d+)*)?j?(?!\w)/i,
-	'operator': /[-+%=]=?|!=|\*\*?=?|\/\/?=?|<[<=>]?|>[=>]?|[&|^~]/,
+	'operator': /[-+%=]=?|!=|:=|\*\*?=?|\/\/?=?|<[<=>]?|>[=>]?|[&|^~]/,
 	'punctuation': /[{}[\];(),.:]/
 };
 

tests/languages/python/operator_feature.test

@@ -7,6 +7,7 @@
 > >= >>
 = ==
 !=
+:=
 & | ^ ~
 
 ----------------------------------------------------
@@ -21,9 +22,10 @@
 	["operator", ">"], ["operator", ">="], ["operator", ">>"],
 	["operator", "="], ["operator", "=="],
 	["operator", "!="],
+	["operator", ":="],
 	["operator", "&"], ["operator", "|"], ["operator", "^"], ["operator", "~"]
 ]
 
 ----------------------------------------------------
 
-Checks for all operators.
+Checks for all operators.