escape consecutive unpaired surrogates (#2576)

fixes #2569
2017-12-11 01:15:44 +08:00
parent bf000beae7
commit 93f3b2b114
3 changed files with 29 additions and 5 deletions
--- a/lib/output.js
+++ b/lib/output.js
@@ -121,11 +121,16 @@ function OutputStream(options) {
            }
        });
    } : function(str) {
-        return str.replace(/[\ud800-\udbff](?![\udc00-\udfff])/g, function(ch) {
-            return "\\u" + ch.charCodeAt(0).toString(16);
-        }).replace(/(^|[^\ud800-\udbff])([\udc00-\udfff])/g, function(match, prefix, ch) {
-            return prefix + "\\u" + ch.charCodeAt(0).toString(16);
-        });
+        var s = "";
+        for (var i = 0, len = str.length; i < len; i++) {
+            if (is_surrogate_pair_head(str[i]) && !is_surrogate_pair_tail(str[i + 1])
+                || is_surrogate_pair_tail(str[i]) && !is_surrogate_pair_head(str[i - 1])) {
+                s += "\\u" + str.charCodeAt(i).toString(16);
+            } else {
+                s += str[i];
+            }
+        }
+        return s;
    };

    function make_string(str, quote) {