YAML: Improved key pattern (#2561)

Author: RunDevelopment

components/prism-yaml.js

@@ -8,6 +8,12 @@
 	// https://yaml.org/spec/1.2/spec.html#c-ns-properties(n,c)
 	var properties = '(?:' + tag.source + '(?:[ \t]+' + anchorOrAlias.source + ')?|'
 		+ anchorOrAlias.source + '(?:[ \t]+' + tag.source + ')?)';
+	// https://yaml.org/spec/1.2/spec.html#ns-plain(n,c)
+	// This is a simplified version that doesn't support "#" and multiline keys
+	// All these long scarry character classes are simplified versions of YAML's characters
+	var plainKey = /(?:[^\s\x00-\x08\x0e-\x1f!"#%&'*,\-:>?@[\]`{|}\x7f-\x84\x86-\x9f\ud800-\udfff\ufffe\uffff]|[?:-]<PLAIN>)(?:[ \t]*(?:(?![#:])<PLAIN>|:<PLAIN>))*/.source
+		.replace(/<PLAIN>/g, function () { return /[^\s\x00-\x08\x0e-\x1f,[\]{}\x7f-\x84\x86-\x9f\ud800-\udfff\ufffe\uffff]/.source; });
+	var string = /"(?:[^"\\\r\n]|\\.)*"|'(?:[^'\\\r\n]|\\.)*'/.source;
 
 	/**
 	 *
@@ -31,9 +37,11 @@
 		},
 		'comment': /#.*/,
 		'key': {
-			pattern: RegExp(/((?:^|[:\-,[{\r\n?])[ \t]*(?:<<prop>>[ \t]+)?)[^\r\n{[\]},#\s]+?(?=\s*:\s)/.source
-				.replace(/<<prop>>/g, function () { return properties; })),
+			pattern: RegExp(/((?:^|[:\-,[{\r\n?])[ \t]*(?:<<prop>>[ \t]+)?)<<key>>(?=\s*:\s)/.source
+				.replace(/<<prop>>/g, function () { return properties; })
+				.replace(/<<key>>/g, function () { return '(?:' + plainKey + '|' + string + ')'; })),
 			lookbehind: true,
+			greedy: true,
 			alias: 'atrule'
 		},
 		'directive': {
@@ -57,8 +65,7 @@
 			alias: 'important'
 		},
 		'string': {
-			// \2 because of the lookbehind group
-			pattern: createValuePattern(/("|')(?:(?!\2)[^\\\r\n]|\\.)*\2/.source),
+			pattern: createValuePattern(string),
 			lookbehind: true,
 			greedy: true
 		},

components/prism-yaml.min.js

@@ -1,15 +1,21 @@
 ---
 foo: 4
 FooBar : 5
+hello the-world: 23
+"\"foo# : {}[]": 23
+'\'foo# : {}[]': 23
 
 ----------------------------------------------------
 
 [
 	["punctuation", "---"],
 	["key", "foo"], ["punctuation", ":"], ["number", "4"],
-	["key", "FooBar"], ["punctuation", ":"], ["number", "5"]
+	["key", "FooBar"], ["punctuation", ":"], ["number", "5"],
+	["key", "hello the-world"], ["punctuation", ":"], ["number", "23"],
+	["key", "\"\\\"foo# : {}[]\""], ["punctuation", ":"], ["number", "23"],
+	["key", "'\\'foo# : {}[]'"], ["punctuation", ":"], ["number", "23"]
 ]
 
 ----------------------------------------------------
 
-Checks for keys.
+Checks for keys.