JS: Improved regex detection (#2465)

Author: RunDevelopment

components/prism-javascript.js

@@ -26,7 +26,7 @@ Prism.languages.javascript['class-name'][0].pattern = /(\b(?:class|interface|ext
 
 Prism.languages.insertBefore('javascript', 'keyword', {
 	'regex': {
-		pattern: /((?:^|[^$\w\xA0-\uFFFF."'\])\s])\s*)\/(?:\[(?:[^\]\\\r\n]|\\.)*]|\\.|[^/\\\[\r\n])+\/[gimyus]{0,6}(?=(?:\s|\/\*(?:[^*]|\*(?!\/))*\*\/)*(?:$|[\r\n,.;:})\]]|\/\/))/,
+		pattern: /((?:^|[^$\w\xA0-\uFFFF."'\])\s]|\b(?:return|yield))\s*)\/(?:\[(?:[^\]\\\r\n]|\\.)*]|\\.|[^/\\\[\r\n])+\/[gimyus]{0,6}(?=(?:\s|\/\*(?:[^*]|\*(?!\/))*\*\/)*(?:$|[\r\n,.;:})\]]|\/\/))/,
 		lookbehind: true,
 		greedy: true
 	},

components/prism-javascript.min.js

@@ -1468,7 +1468,7 @@ Prism.languages.javascript['class-name'][0].pattern = /(\b(?:class|interface|ext
 
 Prism.languages.insertBefore('javascript', 'keyword', {
 	'regex': {
-		pattern: /((?:^|[^$\w\xA0-\uFFFF."'\])\s])\s*)\/(?:\[(?:[^\]\\\r\n]|\\.)*]|\\.|[^/\\\[\r\n])+\/[gimyus]{0,6}(?=(?:\s|\/\*(?:[^*]|\*(?!\/))*\*\/)*(?:$|[\r\n,.;:})\]]|\/\/))/,
+		pattern: /((?:^|[^$\w\xA0-\uFFFF."'\])\s]|\b(?:return|yield))\s*)\/(?:\[(?:[^\]\\\r\n]|\\.)*]|\\.|[^/\\\[\r\n])+\/[gimyus]{0,6}(?=(?:\s|\/\*(?:[^*]|\*(?!\/))*\*\/)*(?:$|[\r\n,.;:})\]]|\/\/))/,
 		lookbehind: true,
 		greedy: true
 	},

prism.js

@@ -11,6 +11,8 @@
 
 let a = /regex/m // comment
 let b = condition ? /regex/ : /another one/
+return /regex/;
+yield /regex/;
 
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@@ -38,7 +40,13 @@ let b = condition ? /regex/ : /another one/
 	["operator", "?"],
 	["regex", "/regex/"],
 	["operator", ":"],
-	["regex", "/another one/"]
+	["regex", "/another one/"],
+	["keyword", "return"],
+	["regex", "/regex/"],
+	["punctuation", ";"],
+	["keyword", "yield"],
+	["regex", "/regex/"],
+	["punctuation", ";"]
 ]
 
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