[gtk/wip/otte/for-master: 3/3] css: Emit a special error for a common error

[Benjamin Otte <otte src gnome org>]

commit 0546253f246bc2020ada24a666915af8a02c137a
Author: Benjamin Otte <otte redhat com>
Date:   Thu Oct 21 00:05:56 2021 +0200

    css: Emit a special error for a common error
    
    This CSS:
      calc(5px+3px)
    is wrong because it gets broken to:
      calc(  5px  +3px  )
    which is 2 numbers inside the calc, and what you want is:
      calc(  5px  +  3px  )
    but you need to add a space to get this, like so:
      calc(5px + 3px)
    which is the recommended way to write calc() statements.
    
    So whenever we encounter an error, check if the next token is a signed
    number and if so, include it in the error message.

 gtk/gtkcsscalcvalue.c | 8 ++++++++
 1 file changed, 8 insertions(+)
---
diff --git a/gtk/gtkcsscalcvalue.c b/gtk/gtkcsscalcvalue.c
index ad7380b990..d0731b267b 100644
--- a/gtk/gtkcsscalcvalue.c
+++ b/gtk/gtkcsscalcvalue.c
@@ -166,6 +166,14 @@ gtk_css_calc_value_parse_sum (GtkCssParser           *parser,
         }
       else
         {
+          if (gtk_css_parser_has_token (parser, GTK_CSS_TOKEN_SIGNED_INTEGER) ||
+              gtk_css_parser_has_token (parser, GTK_CSS_TOKEN_SIGNED_NUMBER) ||
+              gtk_css_parser_has_token (parser, GTK_CSS_TOKEN_SIGNED_INTEGER_DIMENSION) ||
+              gtk_css_parser_has_token (parser, GTK_CSS_TOKEN_SIGNED_DIMENSION))
+            {
+              gtk_css_parser_error_syntax (parser, "Unexpected signed number, did you forget a space between 
sign and number?");
+              gtk_css_parser_consume_token (parser);
+            }
           break;
         }