Update Crystal keywords (#1092)

- Add `select`, `uninitialized` and `__END_LINE__`
- Remove `ifdef`

components/prism-crystal.js

@@ -1,7 +1,7 @@
 (function(Prism) {
 	Prism.languages.crystal = Prism.languages.extend('ruby', {
 		keyword: [
-			/\b(?:abstract|alias|as|asm|begin|break|case|class|def|do|else|elsif|end|ensure|enum|extend|for|fun|if|ifdef|include|instance_sizeof|lib|macro|module|next|of|out|pointerof|private|protected|rescue|return|require|self|sizeof|struct|super|then|type|typeof|union|unless|until|when|while|with|yield|__DIR__|__FILE__|__LINE__)\b/,
+			/\b(?:abstract|alias|as|asm|begin|break|case|class|def|do|else|elsif|end|ensure|enum|extend|for|fun|if|include|instance_sizeof|lib|macro|module|next|of|out|pointerof|private|protected|rescue|return|require|select|self|sizeof|struct|super|then|type|typeof|uninitialized|union|unless|until|when|while|with|yield|__DIR__|__END_LINE__|__FILE__|__LINE__)\b/,
 			{
 				pattern: /(\.\s*)(?:is_a|responds_to)\?/,
 				lookbehind: true

tests/languages/crystal/keyword_feature.test

@@ -2,14 +2,15 @@ abstract alias as asm begin break case
 class;
 def do else elsif
 end ensure enum extend for fun
-if ifdef include instance_sizeof
+if include instance_sizeof
 .is_a?
 lib macro module next of out pointerof
 private protected rescue
 .responds_to?
-return require self sizeof struct super
-then type typeof union unless until when
-while with yield __DIR__ __FILE__ __LINE__
+return require select self sizeof struct super
+then type typeof uninitialized union unless
+until when while with yield __DIR__ __END_LINE__
+__FILE__ __LINE__
 
 ----------------------------------------------------
 
@@ -18,14 +19,15 @@ while with yield __DIR__ __FILE__ __LINE__
 	["keyword", "class"], ["punctuation", ";"],
 	["keyword", "def"], ["keyword", "do"], ["keyword", "else"], ["keyword", "elsif"],
 	["keyword", "end"], ["keyword", "ensure"], ["keyword", "enum"], ["keyword", "extend"], ["keyword", "for"], ["keyword", "fun"],
-	["keyword", "if"], ["keyword", "ifdef"], ["keyword", "include"], ["keyword", "instance_sizeof"],
+	["keyword", "if"], ["keyword", "include"], ["keyword", "instance_sizeof"],
 	["punctuation", "."], ["keyword", "is_a?"],
 	["keyword", "lib"], ["keyword", "macro"], ["keyword", "module"], ["keyword", "next"], ["keyword", "of"], ["keyword", "out"], ["keyword", "pointerof"],
 	["keyword", "private"], ["keyword", "protected"], ["keyword", "rescue"],
 	["punctuation", "."], ["keyword", "responds_to?"],
-	["keyword", "return"], ["keyword", "require"], ["keyword", "self"], ["keyword", "sizeof"], ["keyword", "struct"], ["keyword", "super"],
-	["keyword", "then"], ["keyword", "type"], ["keyword", "typeof"], ["keyword", "union"], ["keyword", "unless"], ["keyword", "until"], ["keyword", "when"],
-	["keyword", "while"], ["keyword", "with"], ["keyword", "yield"], ["keyword", "__DIR__"], ["keyword", "__FILE__"], ["keyword", "__LINE__"]
+	["keyword", "return"], ["keyword", "require"], ["keyword", "select"], ["keyword", "self"], ["keyword", "sizeof"], ["keyword", "struct"], ["keyword", "super"],
+	["keyword", "then"], ["keyword", "type"], ["keyword", "typeof"], ["keyword", "uninitialized"], ["keyword", "union"], ["keyword", "unless"],
+	["keyword", "until"], ["keyword", "when"], ["keyword", "while"], ["keyword", "with"], ["keyword", "yield"], ["keyword", "__DIR__"], ["keyword", "__END_LINE__"],
+	["keyword", "__FILE__"], ["keyword", "__LINE__"]
 ]
 
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