[gnumeric] GUI: Improve blank check for expression entry.

[Morten Welinder <mortenw src gnome org>]

commit 4371c59ed5e2b787f4565d0e62dbf9fdb9f36dd0
Author: Morten Welinder <terra gnome org>
Date:   Wed Jun 1 11:06:12 2011 -0400

    GUI: Improve blank check for expression entry.

 src/widgets/ChangeLog             |    6 ++++++
 src/widgets/gnumeric-expr-entry.c |   19 +++++++++++--------
 2 files changed, 17 insertions(+), 8 deletions(-)
---
diff --git a/src/widgets/ChangeLog b/src/widgets/ChangeLog
index 6e8965f..1d0e798 100644
--- a/src/widgets/ChangeLog
+++ b/src/widgets/ChangeLog
@@ -1,3 +1,9 @@
+2011-06-01  Morten Welinder  <terra gnome org>
+
+	* gnumeric-expr-entry.c (gnm_expr_entry_is_blank): Move code after
+	preconditions.  Make blank-check unicode based and avoid memory
+	allocation.
+
 2011-05-31  Andreas J. Guelzow <aguelzow pyrshep ca>
 
 	* gnumeric-expr-entry.c (gee_check_tooltip): don't show tooltips in
diff --git a/src/widgets/gnumeric-expr-entry.c b/src/widgets/gnumeric-expr-entry.c
index 68d016a..3246769 100644
--- a/src/widgets/gnumeric-expr-entry.c
+++ b/src/widgets/gnumeric-expr-entry.c
@@ -2662,21 +2662,24 @@ gnm_expr_entry_is_cell_ref (GnmExprEntry *gee, Sheet *sheet,
 gboolean
 gnm_expr_entry_is_blank	(GnmExprEntry *gee)
 {
-	GtkEntry *entry = gnm_expr_entry_get_entry (gee);
-	char const *text = gtk_entry_get_text (entry);
-	char *new_text;
-	int len;
+	GtkEntry *entry;
+	char const *text;
 
 	g_return_val_if_fail (IS_GNM_EXPR_ENTRY (gee), FALSE);
 
+	entry = gnm_expr_entry_get_entry (gee);
+
+	text = gtk_entry_get_text (entry);
 	if (text == NULL)
 		return TRUE;
 
-	new_text = g_strdup (text);
-	len = strlen (g_strstrip(new_text));
-	g_free (new_text);
+	while (*text) {
+		if (!g_unichar_isspace (g_utf8_get_char (text)))
+			return FALSE;
+		text = g_utf8_next_char (text);
+	}
 
-	return (len == 0);
+	return TRUE;
 }
 
 char *