[Fix] quoteStyle: properly escape only the containing quotes

Author: ljharb

index.js

@@ -74,6 +74,11 @@ var quotes = {
     'double': '"',
     single: "'"
 };
+var quoteREs = {
+    __proto__: null,
+    'double': /(["\\])/g,
+    single: /(['\\])/g
+};
 
 module.exports = function inspect_(obj, options, depth, seen) {
     var opts = options || {};
@@ -432,8 +437,10 @@ function inspectString(str, opts) {
         var trailer = '... ' + remaining + ' more character' + (remaining > 1 ? 's' : '');
         return inspectString($slice.call(str, 0, opts.maxStringLength), opts) + trailer;
     }
+    var quoteRE = quoteREs[opts.quoteStyle || 'single'];
+    quoteRE.lastIndex = 0;
     // eslint-disable-next-line no-control-regex
-    var s = $replace.call($replace.call(str, /(['\\])/g, '\\$1'), /[\x00-\x1f]/g, lowbyte);
+    var s = $replace.call($replace.call(str, quoteRE, '\\$1'), /[\x00-\x1f]/g, lowbyte);
     return wrapQuotes(s, 'single', opts);
 }
 

test/quoteStyle.js

@@ -14,10 +14,10 @@ test('quoteStyle option', function (t) {
     t['throws'](function () { inspect(null, { quoteStyle: function () {} }); }, 'a function is not a valid value');
 
     t.equal(inspect('"', { quoteStyle: 'single' }), '\'"\'', 'double quote, quoteStyle: "single"');
-    t.equal(inspect('"', { quoteStyle: 'double' }), '"""', 'double quote, quoteStyle: "double"');
+    t.equal(inspect('"', { quoteStyle: 'double' }), '"\\""', 'double quote, quoteStyle: "double"');
 
     t.equal(inspect('\'', { quoteStyle: 'single' }), '\'\\\'\'', 'single quote, quoteStyle: "single"');
-    t.equal(inspect('\'', { quoteStyle: 'double' }), '"\\\'"', 'single quote, quoteStyle: "double"');
+    t.equal(inspect('\'', { quoteStyle: 'double' }), '"\'"', 'single quote, quoteStyle: "double"');
 
     t.equal(inspect('`', { quoteStyle: 'single' }), '\'`\'', 'backtick, quoteStyle: "single"');
     t.equal(inspect('`', { quoteStyle: 'double' }), '"`"', 'backtick, quoteStyle: "double"');