Parser: improve quoted string escaping

lib/Parser.js

@@ -648,7 +648,12 @@ function parseEnvelopeAddresses(list) {
 
 function parseExpr(o, literals, result, start, useBrackets) {
   start = start || 0;
-  var inQuote = false, lastPos = start - 1, isTop = false, val, isBody = false;
+  var inQuote = false,
+      lastPos = start - 1,
+      isTop = false,
+      isBody = false,
+      escaping = false,
+      val;
 
   if (useBrackets === undefined)
     useBrackets = true;
@@ -669,7 +674,8 @@ function parseExpr(o, literals, result, start, useBrackets) {
         }
       } else if (o.str[i] === '"')
         inQuote = true;
-      else if (o.str[i] === ' ' || o.str[i] === ')'
+      else if (o.str[i] === ' '
+               || o.str[i] === ')'
                || (useBrackets && o.str[i] === ']')) {
         if (i - (lastPos + 1) > 0) {
           val = convStr(o.str.substring(lastPos + 1, i), literals);
@@ -691,12 +697,13 @@ function parseExpr(o, literals, result, start, useBrackets) {
           result.push(innerResult);
         }
       }
-    } else if (o.str[i] === '"' &&
-               (o.str[i - 1] &&
-                (o.str[i - 1] !== '\\'
-                 || (o.str[i - 2] && o.str[i - 2] === '\\')
-                )))
-      inQuote = false;
+    } else if (o.str[i] === '\\')
+      escaping = !escaping;
+    else if (o.str[i] === '"') {
+      if (!escaping)
+        inQuote = false;
+      escaping = false;
+    }
     if (i + 1 === len && len - (lastPos + 1) > 0)
       result.push(convStr(o.str.substring(lastPos + 1), literals));
   }

test/test-parse-expr.js

@@ -48,6 +48,25 @@ var assert = require('assert'),
     expected: ['Who does not think \\"IMAP" is terrible\\bad?'],
     what: 'Quoted string with escaped chars #4'
   },
+  { source: 'ENVELOPE ("Wed, 30 Mar 2014 02:38:23 +0100" "=?ISO-8859-1?Q?##ALLCAPS##123456## - ?= =?ISO-8859-1?Q?[ALERT][P3][ONE.TWO.FR] ?= =?ISO-8859-1?Q?Some Subject Line \\"D:\\\\\\"?=" (("Test Account (Rltvty L)" NIL "account" "test.com")) (("Test Account (Rltvty L)" NIL "account" "test.com")) ((NIL NIL "account" "test.com")) ((NIL NIL "one.two" "test.fr") (NIL NIL "two.three" "test.fr")) NIL NIL NIL "<message@test.eu>")',
+    expected: [
+      'ENVELOPE',
+      [ 'Wed, 30 Mar 2014 02:38:23 +0100',
+        '=?ISO-8859-1?Q?##ALLCAPS##123456## - ?= =?ISO-8859-1?Q?[ALERT][P3][ONE.TWO.FR] ?= =?ISO-8859-1?Q?Some Subject Line "D:\\"?=',
+        [ [ 'Test Account (Rltvty L)', null, 'account', 'test.com' ] ],
+        [ [ 'Test Account (Rltvty L)', null, 'account', 'test.com' ] ],
+        [ [ null, null, 'account', 'test.com' ] ],
+        [ [ null, null, 'one.two', 'test.fr' ],
+          [ null, null, 'two.three', 'test.fr' ]
+        ],
+        null,
+        null,
+        null,
+        '<message@test.eu>'
+      ]
+    ],
+    what: 'Triple backslash in quoted string (GH Issue #345)'
+  },
 ].forEach(function(v) {
   var result;