Fix regex for catch and finally (#1527)

When called as methods on a promise chain, the current regex
would mark `catch` and `finally` as keywords. This regex improvement
ensures they're only caught as part of a `try / catch` block, and are
marked as functions as part of the promise chain.

Author: RunDevelopment

components/prism-javascript.js

@@ -1,11 +1,19 @@
 Prism.languages.javascript = Prism.languages.extend('clike', {
-	'keyword': /\b(?:as|async|await|break|case|catch|class|const|continue|debugger|default|delete|do|else|enum|export|extends|finally|for|from|function|get|if|implements|import|in|instanceof|interface|let|new|null|of|package|private|protected|public|return|set|static|super|switch|this|throw|try|typeof|var|void|while|with|yield)\b/,
+	'keyword': [
+		{
+			pattern: /((?:^|})\s*)(?:catch|finally)\b/,
+			lookbehind: true
+		},
+		/\b(?:as|async|await|break|case|class|const|continue|debugger|default|delete|do|else|enum|export|extends|for|from|function|get|if|implements|import|in|instanceof|interface|let|new|null|of|package|private|protected|public|return|set|static|super|switch|this|throw|try|typeof|var|void|while|with|yield)\b/
+	],
 	'number': /\b(?:0[xX][\dA-Fa-f]+|0[bB][01]+|0[oO][0-7]+|NaN|Infinity)\b|(?:\b\d+\.?\d*|\B\.\d+)(?:[Ee][+-]?\d+)?/,
 	// Allow for all non-ASCII characters (See http://stackoverflow.com/a/2008444)
 	'function': /[_$a-z\xA0-\uFFFF][$\w\xA0-\uFFFF]*(?=\s*\()/i,
 	'operator': /-[-=]?|\+[+=]?|!=?=?|<<?=?|>>?>?=?|=(?:==?|>)?|&[&=]?|\|[|=]?|\*\*?=?|\/=?|~|\^=?|%=?|\?|\.{3}/
 });
 
+Prism.languages.javascript['class-name'].pattern = /(\b(?:class|interface|extends|implements|instanceof|new)\s+)[\w.\\]+/
+
 Prism.languages.insertBefore('javascript', 'keyword', {
 	'regex': {
 		pattern: /((?:^|[^$\w\xA0-\uFFFF."'\])\s])\s*)\/(\[[^\]\r\n]+]|\\.|[^/\\\[\r\n])+\/[gimyu]{0,5}(?=\s*($|[\r\n,.;})\]]))/,

components/prism-javascript.min.js

@@ -725,13 +725,21 @@ Prism.languages.clike = {
 ********************************************** */
 
 Prism.languages.javascript = Prism.languages.extend('clike', {
-	'keyword': /\b(?:as|async|await|break|case|catch|class|const|continue|debugger|default|delete|do|else|enum|export|extends|finally|for|from|function|get|if|implements|import|in|instanceof|interface|let|new|null|of|package|private|protected|public|return|set|static|super|switch|this|throw|try|typeof|var|void|while|with|yield)\b/,
+	'keyword': [
+		{
+			pattern: /((?:^|})\s*)(?:catch|finally)\b/,
+			lookbehind: true
+		},
+		/\b(?:as|async|await|break|case|class|const|continue|debugger|default|delete|do|else|enum|export|extends|for|from|function|get|if|implements|import|in|instanceof|interface|let|new|null|of|package|private|protected|public|return|set|static|super|switch|this|throw|try|typeof|var|void|while|with|yield)\b/
+	],
 	'number': /\b(?:0[xX][\dA-Fa-f]+|0[bB][01]+|0[oO][0-7]+|NaN|Infinity)\b|(?:\b\d+\.?\d*|\B\.\d+)(?:[Ee][+-]?\d+)?/,
 	// Allow for all non-ASCII characters (See http://stackoverflow.com/a/2008444)
 	'function': /[_$a-z\xA0-\uFFFF][$\w\xA0-\uFFFF]*(?=\s*\()/i,
 	'operator': /-[-=]?|\+[+=]?|!=?=?|<<?=?|>>?>?=?|=(?:==?|>)?|&[&=]?|\|[|=]?|\*\*?=?|\/=?|~|\^=?|%=?|\?|\.{3}/
 });
 
+Prism.languages.javascript['class-name'].pattern = /(\b(?:class|interface|extends|implements|instanceof|new)\s+)[\w.\\]+/
+
 Prism.languages.insertBefore('javascript', 'keyword', {
 	'regex': {
 		pattern: /((?:^|[^$\w\xA0-\uFFFF."'\])\s])\s*)\/(\[[^\]\r\n]+]|\\.|[^/\\\[\r\n])+\/[gimyu]{0,5}(?=\s*($|[\r\n,.;})\]]))/,

prism.js

@@ -0,0 +1,35 @@
+fetch('some-resource.json')
+	.then(response => response.json())
+	.catch(console.error);
+
+----------------------------------------------------
+
+[
+	["function", "fetch"],
+	["punctuation", "("],
+	["string", "'some-resource.json'"],
+	["punctuation", ")"],
+	["punctuation", "."],
+	["function", "then"],
+	["punctuation", "("],
+	"response ",
+	["operator", "=>"],
+	" response",
+	["punctuation", "."],
+	["function", "json"],
+	["punctuation", "("],
+	["punctuation", ")"],
+	["punctuation", ")"],
+	["punctuation", "."],
+	["function", "catch"],
+	["punctuation", "("],
+	"console",
+	["punctuation", "."],
+	"error",
+	["punctuation", ")"],
+	["punctuation", ";"]
+]
+
+----------------------------------------------------
+
+Checks for catch function which is not a keyword. See #1526

tests/languages/javascript/issue1526.test

@@ -1,24 +1,28 @@
+catch finally;
+
 as; async; await; break; case;
-catch; class; const; continue; debugger;
+class; const; continue; debugger;
 default; delete; do; else; enum;
-export; extends; finally; for;
+export; extends; for;
 from; function; get; if; implements;
 import; in; instanceof; interface; let;
 new; null; of; package; private;
 protected; public; return; set; static;
-super; switch; this; throw;
-try; typeof; var; void; while;
+super; switch; this; throw; try;
+typeof; var; void; while;
 with; yield;
 
 ----------------------------------------------------
 
 [
+	["keyword", "catch"],
+	["keyword", "finally"], ["punctuation", ";"],
+
 	["keyword", "as"], ["punctuation", ";"],
 	["keyword", "async"], ["punctuation", ";"],
 	["keyword", "await"], ["punctuation", ";"],
 	["keyword", "break"], ["punctuation", ";"],
 	["keyword", "case"], ["punctuation", ";"],
-	["keyword", "catch"], ["punctuation", ";"],
 	["keyword", "class"], ["punctuation", ";"],
 	["keyword", "const"], ["punctuation", ";"],
 	["keyword", "continue"], ["punctuation", ";"],
@@ -30,7 +34,6 @@ with; yield;
 	["keyword", "enum"], ["punctuation", ";"],
 	["keyword", "export"], ["punctuation", ";"],
 	["keyword", "extends"], ["punctuation", ";"],
-	["keyword", "finally"], ["punctuation", ";"],
 	["keyword", "for"], ["punctuation", ";"],
 	["keyword", "from"], ["punctuation", ";"],
 	["keyword", "function"], ["punctuation", ";"],
@@ -67,4 +70,4 @@ with; yield;
 
 ----------------------------------------------------
 
-Checks for all keywords.
+Checks for all keywords.

tests/languages/javascript/keyword_feature.test

@@ -0,0 +1,22 @@
+try { } catch (e) { } finally { }
+
+----------------------------------------------------
+
+[
+	["keyword", "try"],
+	["punctuation", "{"],
+	["punctuation", "}"],
+	["keyword", "catch"],
+	["punctuation", "("],
+	"e",
+	["punctuation", ")"],
+	["punctuation", "{"],
+	["punctuation", "}"],
+	["keyword", "finally"],
+	["punctuation", "{"],
+	["punctuation", "}"]
+]
+
+----------------------------------------------------
+
+Checks for try statements.