Correctly handle some weird escaping (#41)

sindresorhus · Apr 30, 2019 · 23acbfe · 23acbfe
1 parent 5f5fdd3
commit 23acbfe
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Showing 2 changed files with 15 additions and 4 deletions.
diff --git a/index.js b/index.js
@@ -4,6 +4,18 @@ const multiComment = Symbol('multiComment');
 const stripWithoutWhitespace = () => '';
 const stripWithWhitespace = (string, start, end) => string.slice(start, end).replace(/\S/g, ' ');
 
+const isEscaped = (jsonString, qoutePos) => {
+	let i = qoutePos - 1;
+	let numOfBackslash = 0;
+
+	while (jsonString[i] === '\\') {
+		numOfBackslash += 1;
+		i -= 1;
+	}
+
+	return Boolean(numOfBackslash % 2);
+};
+
 module.exports = (jsonString, options = {}) => {
 	const strip = options.whitespace === false ? stripWithoutWhitespace : stripWithWhitespace;
 
@@ -17,7 +29,7 @@ module.exports = (jsonString, options = {}) => {
 		const nextCharacter = jsonString[i + 1];
 
 		if (!insideComment && currentCharacter === '"') {
-			const escaped = jsonString[i - 1] === '\\' && jsonString[i - 2] !== '\\';
+			const escaped = isEscaped(jsonString, i);
 			if (!escaped) {
 				insideString = !insideString;
 			}

diff --git a/test.js b/test.js
@@ -60,7 +60,6 @@ test('line endings - works at EOF', t => {
 	t.is(stripJsonComments('{\r\n\t"a":"b"\r\n} //EOF', options), '{\r\n\t"a":"b"\r\n} ');
 });
 
-test.failing('handles weird escaping', t => {
-	// eslint-disable-next-line no-useless-escape
-	t.is(stripJsonComments('{"x":"x \"sed -e \\\"s/^.\\\\{46\\\\}T//\\\" -e \\\"s/#033/\\\\x1b/g\\\"\""}'), '{"x":"x \"sed -e \\\"s/^.\\\\{46\\\\}T//\\\" -e \\\"s/#033/\\\\x1b/g\\\"\""}');
+test('handles weird escaping', t => {
+	t.is(stripJsonComments(String.raw`{"x":"x \"sed -e \\\"s/^.\\\\{46\\\\}T//\\\" -e \\\"s/#033/\\\\x1b/g\\\"\""}`), String.raw`{"x":"x \"sed -e \\\"s/^.\\\\{46\\\\}T//\\\" -e \\\"s/#033/\\\\x1b/g\\\"\""}`);
 });