Add ECMAScript Unicode literal support

* module/language/ecmascript/tokenize.scm: add unicode literals

* test-suite/tests/ecmascript.test ("parser"): Add new tests for Latin-1
  and Unicode escapes in string literals.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

module/language/ecmascript/tokenize.scm

@@ -1,6 +1,6 @@
 ;;; ECMAScript for Guile
 
-;; Copyright (C) 2009, 2010 Free Software Foundation, Inc.
+;; Copyright (C) 2009, 2010, 2011 Free Software Foundation, Inc.
 
 ;;;; This library is free software; you can redistribute it and/or
 ;;;; modify it under the terms of the GNU Lesser General Public
@@ -150,7 +150,11 @@
                 (else
                  (syntax-error "bad hex character escape" loc (string a b))))))
             ((#\u)
-             (syntax-error "unicode not supported" loc #f))
+             (let* ((a (read-char port))
+                    (b (read-char port))
+                    (c (read-char port))
+                    (d (read-char port)))
+               (integer->char (string->number (string a b c d) 16))))
             (else
              c))))
       (let lp ((str (read-until terms port loc)))

test-suite/tests/ecmascript.test

@@ -48,7 +48,11 @@
   (parse "var x = { foo: 12, bar: \"hello\" };"
          '(begin (var (x (object (foo (number 12))
                                  (bar (string "hello")))))
-                 (begin))))
+                 (begin)))
+  (parse "\"\\x12\";"   ; Latin-1 escape in string literal
+         '(string "\x12"))
+  (parse "\"\\u1234\";" ; Unicode escape in string literal
+         '(string "\u1234")))
 
 
 (define-syntax ecompile