[goffice] GogObject: properly serialize float/double properties.

[Morten Welinder <mortenw src gnome org>]

commit 6525619ea9053ec33b9e0f57bbc53955c6d3da18
Author: Morten Welinder <terra gnome org>
Date:   Tue Apr 22 20:26:15 2014 -0400

    GogObject: properly serialize float/double properties.
    
    g_value_transform specifically says not to use to-string conversions
    for serialization.  It loses precision.

 ChangeLog                      |    3 +++
 goffice/graph/gog-object-xml.c |   22 +++++++++++++++++++---
 2 files changed, 22 insertions(+), 3 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index c119576..1e24497 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 2014-04-22  Morten Welinder  <terra gnome org>
 
+       * goffice/graph/gog-object-xml.c (gog_object_write_property_sax):
+       Properly handle float/double properties.
+
        * goffice/utils/go-format.c (go_format_output_number_to_odf):
        Handle TOK_REPEATED_CHAR.
 
diff --git a/goffice/graph/gog-object-xml.c b/goffice/graph/gog-object-xml.c
index 78665b2..6f55a98 100644
--- a/goffice/graph/gog-object-xml.c
+++ b/goffice/graph/gog-object-xml.c
@@ -72,7 +72,7 @@ gog_object_write_property_sax (GogObject const *obj, GParamSpec *pspec, GsfXMLOu
        GValue   value = { 0 };
 
        g_value_init (&value, prop_type);
-       g_object_get_property  (G_OBJECT (obj), pspec->name, &value);
+       g_object_get_property (G_OBJECT (obj), pspec->name, &value);
 
        /* No need to save default values */
        if (((pspec->flags & GOG_PARAM_POSITION) &&
@@ -92,8 +92,6 @@ gog_object_write_property_sax (GogObject const *obj, GParamSpec *pspec, GsfXMLOu
        case G_TYPE_UINT:
        case G_TYPE_LONG:
        case G_TYPE_ULONG:
-       case G_TYPE_FLOAT:
-       case G_TYPE_DOUBLE:
        case G_TYPE_ENUM:
        case G_TYPE_FLAGS: {
                GValue str = { 0 };
@@ -107,6 +105,24 @@ gog_object_write_property_sax (GogObject const *obj, GParamSpec *pspec, GsfXMLOu
                break;
        }
 
+       case G_TYPE_FLOAT:
+       case G_TYPE_DOUBLE: {
+               GValue vd = { 0 };
+               GString *str = g_string_new (NULL);
+
+               g_value_init (&vd, G_TYPE_DOUBLE);
+               g_value_transform (&value, &vd);
+               go_dtoa (str, "!g", g_value_get_double (&vd));
+               g_value_unset (&vd);
+
+               gsf_xml_out_start_element (output, "property");
+               gsf_xml_out_add_cstr_unchecked (output, "name", pspec->name);
+               gsf_xml_out_add_cstr (output, NULL, str->str);
+               gsf_xml_out_end_element (output); /* </property> */
+               g_string_free (str, TRUE);
+               break;
+       }
+
        case G_TYPE_STRING: {
                char const *str = g_value_get_string (&value);
                if (str != NULL) {