[libcroco] cr-tknzr: Handle signed units

[Jasper St. Pierre <jstpierre src gnome org>]

commit 1c3a1096307e68113f3f22dd93bd3c2421c81953
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Tue Oct 16 12:35:54 2012 -0400

    cr-tknzr: Handle signed units
    
    Parse something like '-20px' correctly.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=686239

 src/cr-tknzr.c                       |   24 ++++++++++++++++++++++--
 tests/test-inputs/test1.css          |    4 +++-
 tests/test-output-refs/test1.css.out |    4 +++-
 3 files changed, 28 insertions(+), 4 deletions(-)
---
diff --git a/src/cr-tknzr.c b/src/cr-tknzr.c
index 64924ed..6512c98 100644
--- a/src/cr-tknzr.c
+++ b/src/cr-tknzr.c
@@ -1465,6 +1465,12 @@ cr_tknzr_parse_important (CRTknzr * a_this,
  * param a_num out parameter. The parsed number.
  * return CR_OK upon successfull completion, 
  *an error code otherwise.
+ *
+ *The CSS specification says that numbers may be
+ *preceeded by '+' or '-' to indicate the sign.
+ *Technically, the "num" construction as defined
+ *by the tokenizer doesn't allow this, but we parse
+ *it here for simplicity.
  */
 static enum CRStatus
 cr_tknzr_parse_num (CRTknzr * a_this, 
@@ -1480,13 +1486,22 @@ cr_tknzr_parse_num (CRTknzr * a_this,
         gdouble numerator, denominator = 1;
         CRInputPos init_pos;
         CRParsingLocation location = {0} ;
+        int sign = 1;
 
         g_return_val_if_fail (a_this && PRIVATE (a_this)
                               && PRIVATE (a_this)->input, 
                               CR_BAD_PARAM_ERROR);
 
         RECORD_INITIAL_POS (a_this, &init_pos);
-        READ_NEXT_CHAR (a_this, &cur_char);        
+        READ_NEXT_CHAR (a_this, &cur_char);
+
+        if (cur_char == '+' || cur_char == '-') {
+                if (cur_char == '-') {
+                        sign = -1;
+                }
+                READ_NEXT_CHAR (a_this, &cur_char);
+        }
+
         if (IS_NUM (cur_char)) {
                 numerator = (cur_char - '0');
                 parsing_dec = FALSE;
@@ -1539,7 +1554,7 @@ cr_tknzr_parse_num (CRTknzr * a_this,
          *Now, set the output param values.
          */
         if (status == CR_OK) {
-                gdouble val = numerator / denominator;
+                gdouble val = (numerator / denominator) * sign;
                 if (*a_num == NULL) {
                         *a_num = cr_num_new_with_val (val, val_type);
 
@@ -2160,6 +2175,8 @@ cr_tknzr_get_next_token (CRTknzr * a_this, CRToken ** a_tk)
                                                                   &str->location) ;
                                 }
                                 goto done;
+                        } else {
+                                goto parse_number;
                         }
                 }
                 break;
@@ -2353,6 +2370,9 @@ cr_tknzr_get_next_token (CRTknzr * a_this, CRToken ** a_tk)
         case '8':
         case '9':
         case '.':
+        case '+':
+        /* '-' case is handled separately above for --> comments */
+        parse_number:
                 {
                         CRNum *num = NULL;
 
diff --git a/tests/test-inputs/test1.css b/tests/test-inputs/test1.css
index d432405..b03c8a4 100644
--- a/tests/test-inputs/test1.css
+++ b/tests/test-inputs/test1.css
@@ -309,6 +309,8 @@ border-left-width : 1px;
 
 .postbody { line-height: 18px} 
 
- 
+.magic {
+    margin-left: -20px;
+} 
 
 /* END of formIE.css */ 
diff --git a/tests/test-output-refs/test1.css.out b/tests/test-output-refs/test1.css.out
index d432405..b03c8a4 100644
--- a/tests/test-output-refs/test1.css.out
+++ b/tests/test-output-refs/test1.css.out
@@ -309,6 +309,8 @@ border-left-width : 1px;
 
 .postbody { line-height: 18px} 
 
- 
+.magic {
+    margin-left: -20px;
+} 
 
 /* END of formIE.css */