Bug 1509493 - Fix markup generation for nested email addresses r=BenB

In mozTXTToHTMLConv, FindURL is not able to correctly calculate replaceBefore for nested email addresses/URLs such as john@doe.org}john@doe.org. As a workaround, we keep track of the end of the last URL HTML markup in the output string and skip any subsequent URLs whose replaceBefore would cut into this markup.

Differential Revision: https://phabricator.services.mozilla.com/D13391

--HG--
extra : moz-landing-system : lando

netwerk/streamconv/converters/mozTXTToHTMLConv.cpp

@@ -1086,6 +1086,8 @@ mozTXTToHTMLConv::ScanTXT(const char16_t * aInString, int32_t aInStringLength, u
   uint32_t structPhrase_italic = 0;
   uint32_t structPhrase_code = 0;
 
+  uint32_t endOfLastURLOutput = 0;
+
   nsAutoString outputHTML;  // moved here for performance increase
 
   for(uint32_t i = 0; int32_t(i) < aInStringLength;)
@@ -1173,8 +1175,13 @@ mozTXTToHTMLConv::ScanTXT(const char16_t * aInString, int32_t aInStringLength, u
                        structPhrase_underline + structPhrase_code == 0
                        /* workaround for bug #19445 */ )
           {
+            // Don't cut into previously inserted HTML (bug 1509493)
+            if (aOutString.Length() - replaceBefore < endOfLastURLOutput) {
+              break;
+            }
             aOutString.Cut(aOutString.Length() - replaceBefore, replaceBefore);
             aOutString += outputHTML;
+            endOfLastURLOutput = aOutString.Length();
             i += replaceAfter + 1;
             continue;
           }

netwerk/test/unit/test_mozTXTToHTMLConv.js

@@ -148,6 +148,16 @@ function run_test() {
     {
       input: "test http://www.map.com/map.php?t=Nova_Scotia&markers=//Not_a_survey||description=plm2 test",
       url: "http://www.map.com/map.php?t=Nova_Scotia&markers=//Not_a_survey||description=plm2"
+    },
+    {
+      input: "bug#1509493 (john@mozilla.org)john@mozilla.org test",
+      url: "mailto:john@mozilla.org",
+      text: "john@mozilla.org"
+    },
+    {
+      input: "bug#1509493 {john@mozilla.org}john@mozilla.org test",
+      url: "mailto:john@mozilla.org",
+      text: "john@mozilla.org"
     }
   ];
 
@@ -210,13 +220,23 @@ function run_test() {
     return ' href="' + url + '"';
   }
 
+  function linkText(plaintext) {
+    return '>' + plaintext + '</a>';
+  }
+
   for (let i = 0; i < scanTXTtests.length; i++) {
     let t = scanTXTtests[i];
     let output = converter.scanTXT(t.input, Ci.mozITXTToHTMLConv.kURLs);
     let link = hrefLink(t.url);
+    let text;
+    if (t.text)
+      text = linkText(t.text);
     if (!output.includes(link))
       do_throw("Unexpected conversion by scanTXT: input=" + t.input +
                ", output=" + output + ", link=" + link);
+    if (text && !output.includes(text))
+      do_throw("Unexpected conversion by scanTXT: input=" + t.input +
+               ", output=" + output + ", text=" + text);
   }
 
   for (let i = 0; i < scanHTMLtests.length; i++) {