Kotlin: Added char token and improved string interpolation (#3225)

components/prism-kotlin.js

@@ -22,47 +22,67 @@
 
 	delete Prism.languages.kotlin['class-name'];
 
+	var interpolationInside = {
+		'interpolation-punctuation': {
+			pattern: /^\$\{?|\}$/,
+			alias: 'punctuation'
+		},
+		'expression': {
+			pattern: /[\s\S]+/,
+			inside: Prism.languages.kotlin
+		}
+	};
+
 	Prism.languages.insertBefore('kotlin', 'string', {
-		'raw-string': {
-			pattern: /("""|''')[\s\S]*?\1/,
-			alias: 'string'
-			// See interpolation below
+		// https://kotlinlang.org/spec/expressions.html#string-interpolation-expressions
+		'string-literal': [
+			{
+				pattern: /"""(?:[^$]|\$(?:(?!\{)|\{[^{}]*\}))*?"""/,
+				alias: 'multiline',
+				inside: {
+					'interpolation': {
+						pattern: /\$(?:[a-z_]\w*|\{[^{}]*\})/i,
+						inside: interpolationInside
+					},
+					'string': /[\s\S]+/
+				}
+			},
+			{
+				pattern: /"(?:[^"\\\r\n$]|\\.|\$(?:(?!\{)|\{[^{}]*\}))*"/,
+				alias: 'singleline',
+				inside: {
+					'interpolation': {
+						pattern: /((?:^|[^\\])(?:\\{2})*)\$(?:[a-z_]\w*|\{[^{}]*\})/i,
+						lookbehind: true,
+						inside: interpolationInside
+					},
+					'string': /[\s\S]+/
+				}
+			}
+		],
+		'char': {
+			// https://kotlinlang.org/spec/expressions.html#character-literals
+			pattern: /'(?:[^'\\\r\n]|\\(?:.|u[a-fA-F0-9]{0,4}))'/,
+			greedy: true
 		}
 	});
+
+	delete Prism.languages.kotlin['string'];
+
 	Prism.languages.insertBefore('kotlin', 'keyword', {
 		'annotation': {
 			pattern: /\B@(?:\w+:)?(?:[A-Z]\w*|\[[^\]]+\])/,
 			alias: 'builtin'
 		}
 	});
+
 	Prism.languages.insertBefore('kotlin', 'function', {
 		'label': {
 			pattern: /\b\w+@|@\w+\b/,
 			alias: 'symbol'
 		}
 	});
 
-	var interpolation = [
-		{
-			pattern: /\$\{[^}]+\}/,
-			inside: {
-				'delimiter': {
-					pattern: /^\$\{|\}$/,
-					alias: 'variable'
-				},
-				rest: Prism.languages.kotlin
-			}
-		},
-		{
-			pattern: /\$\w+/,
-			alias: 'variable'
-		}
-	];
-
-	Prism.languages.kotlin['string'].inside = Prism.languages.kotlin['raw-string'].inside = {
-		interpolation: interpolation
-	};
-
 	Prism.languages.kt = Prism.languages.kotlin;
 	Prism.languages.kts = Prism.languages.kotlin;
 }(Prism));

tests/languages/kotlin/char_feature.test

@@ -0,0 +1,11 @@
+'a'
+'\n'
+'\uFFFF'
+
+----------------------------------------------------
+
+[
+	["char", "'a'"],
+	["char", "'\\n'"],
+	["char", "'\\uFFFF'"]
+]

tests/languages/kotlin/string_feature.test

@@ -0,0 +1,113 @@
+""
+"foo"
+"\"\""
+
+""""""
+"""Foo "bar"" baz"""
+"""
+"Foo"
+bar
+"""
+
+// interpolation
+
+"$foo ${bar} ${'$'} ${foobar()}"
+"""
+$foo ${bar}
+${'$'} ${foobar()}
+"""
+
+----------------------------------------------------
+
+[
+	["string-literal", [
+		["string", "\"\""]
+	]],
+	["string-literal", [
+		["string", "\"foo\""]
+	]],
+	["string-literal", [
+		["string", "\"\\\"\\\"\""]
+	]],
+
+	["string-literal", [
+		["string", "\"\"\"\"\"\""]
+	]],
+	["string-literal", [
+		["string", "\"\"\"Foo \"bar\"\" baz\"\"\""]
+	]],
+	["string-literal", [
+		["string", "\"\"\"\r\n\"Foo\"\r\nbar\r\n\"\"\""]
+	]],
+
+	["comment", "// interpolation"],
+
+	["string-literal", [
+		["string", "\""],
+		["interpolation", [
+			["interpolation-punctuation", "$"],
+			["expression", ["foo"]]
+		]],
+		["string", " "],
+		["interpolation", [
+			["interpolation-punctuation", "${"],
+			["expression", ["bar"]],
+			["interpolation-punctuation", "}"]
+		]],
+		["string", " "],
+		["interpolation", [
+			["interpolation-punctuation", "${"],
+			["expression", [
+				["char", "'$'"]
+			]],
+			["interpolation-punctuation", "}"]
+		]],
+		["string", " "],
+		["interpolation", [
+			["interpolation-punctuation", "${"],
+			["expression", [
+				["function", "foobar"],
+				["punctuation", "("],
+				["punctuation", ")"]
+			]],
+			["interpolation-punctuation", "}"]
+		]],
+		["string", "\""]
+	]],
+	["string-literal", [
+		["string", "\"\"\"\r\n"],
+		["interpolation", [
+			["interpolation-punctuation", "$"],
+			["expression", ["foo"]]
+		]],
+		["string", " "],
+		["interpolation", [
+			["interpolation-punctuation", "${"],
+			["expression", ["bar"]],
+			["interpolation-punctuation", "}"]
+		]],
+		["string", "\r\n"],
+		["interpolation", [
+			["interpolation-punctuation", "${"],
+			["expression", [
+				["char", "'$'"]
+			]],
+			["interpolation-punctuation", "}"]
+		]],
+		["string", " "],
+		["interpolation", [
+			["interpolation-punctuation", "${"],
+			["expression", [
+				["function", "foobar"],
+				["punctuation", "("],
+				["punctuation", ")"]
+			]],
+			["interpolation-punctuation", "}"]
+		]],
+		["string", "\r\n\"\"\""]
+	]]
+]
+
+----------------------------------------------------
+
+Checks for raw strings.