[njs] Fixed String.prototype.toUTF8() function.

[Igor Sysoev]

details:   http://hg.nginx.org/njs/rev/ab1f67b69707
branches:  
changeset: 453:ab1f67b69707
user:      Igor Sysoev <igor at sysoev.ru>
date:      Wed Feb 28 16:20:11 2018 +0300
description:
Fixed String.prototype.toUTF8() function.

A byte string returned by String.prototype.toUTF8() had length equal
to its size so the string can be processed later as an ASCII string.

diffstat:

 njs/njs_string.c         |  5 +++++
 njs/test/njs_unit_test.c |  9 +++++++++
 2 files changed, 14 insertions(+), 0 deletions(-)

diffs (34 lines):

diff -r 0f1c3efcd894 -r ab1f67b69707 njs/njs_string.c
--- a/njs/njs_string.c	Tue Feb 27 14:11:00 2018 +0300
+++ b/njs/njs_string.c	Wed Feb 28 16:20:11 2018 +0300
@@ -1051,6 +1051,11 @@ njs_string_slice(njs_vm_t *vm, njs_value
         start += slice->start;
         size = slice->length;
 
+        if (string->length == 0) {
+            /* Byte string. */
+            length = 0;
+        }
+
     } else {
         /* UTF-8 string. */
         end = start + string->size;
diff -r 0f1c3efcd894 -r ab1f67b69707 njs/test/njs_unit_test.c
--- a/njs/test/njs_unit_test.c	Tue Feb 27 14:11:00 2018 +0300
+++ b/njs/test/njs_unit_test.c	Wed Feb 28 16:20:11 2018 +0300
@@ -3529,6 +3529,15 @@ static njs_unit_test_t  njs_test[] =
     { nxt_string("'α'.toUTF8()[0]"),
       nxt_string("\xCE") },
 
+    { nxt_string("/^\\x80$/.test('\\x80'.toBytes())"),
+      nxt_string("true") },
+
+    { nxt_string("/^\\xC2\\x80$/.test('\\x80'.toUTF8())"),
+      nxt_string("true") },
+
+    { nxt_string("'α'.toUTF8().toBytes()"),
+      nxt_string("α") },
+
     { nxt_string("var a = 'a'.toBytes() + 'α'; a + a.length"),
       nxt_string("aα3") },