Add function to set a feature as used and use it for a first feature:

Credit Notes.
Other changes in this commit:
* The feature code moved to core-utils, because the engine can't use
app-utils.
* I remove the gettext wrapper around the feature description. As
mentioned on the mailing list, by definition unknown features can't have
translated descriptions.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@21981 57a11ea4-9604-0410-9ed3-97b8803252fd

po/POTFILES.in

@@ -10,7 +10,6 @@ src/app-utils/gnc-component-manager.c
 src/app-utils/gnc-entry-quickfill.c
 src/app-utils/gnc-euro.c
 src/app-utils/gnc-exp-parser.c
-src/app-utils/gnc-features.c
 src/app-utils/gnc-gettext-util.c
 src/app-utils/gnc-helpers.c
 src/app-utils/gnc-help-utils.c
@@ -125,6 +124,7 @@ src/calculation/fin-main.c
 src/calculation/gncmod-calculation.c
 src/calculation/numeric_ops.c
 src/core-utils/binreloc.c
+src/core-utils/gnc-features.c
 src/core-utils/gnc-filepath-utils.c
 src/core-utils/gnc-gconf-utils.c
 src/core-utils/gnc-gdate-utils.c

src/app-utils/Makefile.am

@@ -47,7 +47,6 @@ libgncmod_app_utils_la_SOURCES = \
   gnc-entry-quickfill.c \
   gnc-euro.c \
   gnc-exp-parser.c \
-  gnc-features.c \
   gnc-gettext-util.c \
   gnc-helpers.c \
   gnc-sx-instance-model.c \
@@ -71,7 +70,6 @@ gncinclude_HEADERS = \
   gnc-entry-quickfill.h \
   gnc-euro.h \
   gnc-exp-parser.h \
-  gnc-features.h \
   gnc-gettext-util.h \
   gnc-help-utils.h \
   gnc-helpers.h \

src/core-utils/Makefile.am

@@ -4,6 +4,7 @@ lib_LTLIBRARIES = libgnc-core-utils.la
 
 libgnc_core_utils_la_SOURCES = \
   binreloc.c \
+  gnc-features.c \
   gnc-filepath-utils.c \
   gnc-gconf-utils.c \
   gnc-gdate-utils.c \
@@ -28,6 +29,7 @@ libgnc_core_utils_la_LIBADD = \
 noinst_HEADERS = \
   binreloc.h \
   gnc-main.h \
+  gnc-features.h \
   gnc-filepath-utils.h \
   gnc-gconf-utils.h \
   gnc-gdate-utils.h \

src/core-utils/gnc-features.c

@@ -29,43 +29,72 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
-#include "gnc-engine.h"
+#include "libqof/qof/qof.h"
 #include "gnc-features.h"
 
+typedef struct {
+        const gchar *key;
+        const gchar *desc;
+} gncFeature;
+
+static GHashTable *features_table = NULL;
+static gncFeature known_features[] =
+{
+        { GNC_FEATURE_CREDIT_NOTES, "Customer and vendor credit notes (requires at least GnuCash 2.5.0)" },
+        { NULL },
+};
+
 /* This static indicates the debugging module that this .o belongs to.  */
-static QofLogModule log_module = GNC_MOD_GUI;
+static QofLogModule log_module = G_LOG_DOMAIN;
 
 /********************************************************************\
 \********************************************************************/
-static void features_test(const gchar *key, KvpValue *value, gpointer data)
+
+static void gnc_features_init ()
 {
-    GList** unknown_features = (GList**) data;
-    char* feature_desc;
+    gint i;
+
+    if (features_table)
+        return;
+
+    features_table = g_hash_table_new (g_str_hash, g_str_equal);
+    for (i = 0; known_features[i].key; i++)
+        g_hash_table_insert (features_table,
+                             g_strdup (known_features[i].key),
+                             g_strdup (known_features[i].desc));
+}
+
+static void gnc_features_test_one(const gchar *key, KvpValue *value, gpointer data)
+{
+    GList **unknown_features;
+    gchar *feature_desc;
 
     g_assert(data);
+    unknown_features = (GList**) data;
 
-    /* XXX: test if 'key' is an unknown feature. */
+    /* Check if this feature is in the known features list. */
+    if (g_hash_table_lookup_extended (features_table, key, NULL, NULL))
+        return;
 
-    /* Yes, it is unknown, so add the description to the list: */
+    /* It is unknown, so add the description to the unknown features list: */
     feature_desc = kvp_value_get_string(value);
     g_assert(feature_desc);
 
     *unknown_features = g_list_prepend(*unknown_features, feature_desc);
 }
 
-/*
- * Right now this is done by a KVP check for a features table.
- * Currently we don't know about any features, so the mere
- * existence of this KVP frame means we have a problem and
- * need to tell the user.
+/* Check if the session requires features unknown to this version of GnuCash.
  *
- * returns a message to display if we found unknown features, NULL if we're okay.
+ * Returns a message to display if we found unknown features, NULL if we're okay.
  */
-gchar *test_unknown_features(QofSession* new_session)
+gchar *gnc_features_test_unknown (QofBook *book)
 {
-    KvpFrame *frame = qof_book_get_slots (qof_session_get_book (new_session));
+    KvpFrame *frame = qof_book_get_slots (book);
     KvpValue *value;
 
+    /* Setup the known_features hash table */
+    gnc_features_init();
+
     g_assert(frame);
     value = kvp_frame_get_value(frame, "features");
 
@@ -76,7 +105,7 @@ gchar *test_unknown_features(QofSession* new_session)
         g_assert(frame);
 
         /* Iterate over the members of this frame for unknown features */
-        kvp_frame_for_each_slot(frame, &features_test, &features_list);
+        kvp_frame_for_each_slot(frame, &gnc_features_test_one, &features_list);
         if (features_list)
         {
             GList *i;
@@ -88,7 +117,7 @@ gchar *test_unknown_features(QofSession* new_session)
 
             for (i = features_list; i; i = i->next)
             {
-                char *tmp = g_strconcat(msg, "\n* ", _(i->data), NULL);
+                char *tmp = g_strconcat(msg, "\n* ", i->data, NULL);
                 g_free (msg);
                 msg = tmp;
             }
@@ -101,3 +130,30 @@ gchar *test_unknown_features(QofSession* new_session)
 
     return NULL;
 }
+
+void gnc_features_set_used (QofBook *book, const gchar *feature)
+{
+    KvpFrame *frame;
+    const gchar *description;
+    gchar *kvp_path;
+
+    g_return_if_fail (book);
+    g_return_if_fail (feature);
+
+    gnc_features_init();
+
+    /* Can't set an unknown feature */
+    description = g_hash_table_lookup (features_table, feature);
+    if (!description)
+    {
+        PWARN("Tried to set unknown feature as used.");
+        return;
+    }
+
+    frame = qof_book_get_slots (book);
+    kvp_path = g_strconcat ("/features/", feature, NULL);
+    kvp_frame_set_string (frame, kvp_path, description);
+    qof_book_kvp_changed (book);
+
+
+}

src/core-utils/gnc-features.h

@@ -30,19 +30,33 @@
  *
  *  These functions help you to manage features that GnuCash supports.
  *  This is mainly used to prevent older GnuCash versions from opening
- *  datasets with data they aren't capable of processing properly.
+ *  book with data they aren't capable of processing properly.
  */
 
 #ifndef GNC_FEATURES_H
 #define GNC_FEATURES_H
 
+/** @name Defined features
+@{
+ */
+#define GNC_FEATURE_CREDIT_NOTES "Credit Notes"
+
+/** @} */
 
 /**
- * Test if the current session relies on features we don't know.
+ * Test if the current book relies on features only introduced in a more
+ * recent version of GnuCash.
  *
  * Returns a message to display if we found unknown features, NULL if we're okay.
  */
-gchar *test_unknown_features(QofSession* new_session);
+gchar *gnc_features_test_unknown (QofBook *book);
+
+/**
+ * Indicate that the current book uses the given feature. This will prevent
+ * older versions of GnuCash that don't support this feature to refuse to load
+ * this book.
+ */
+void gnc_features_set_used (QofBook *book, const gchar *feature);
 
 #endif /* GNC_FEATURES_H */
 /** @} */

src/engine/gncInvoice.c

@@ -37,6 +37,7 @@
 #include "gncBillTermP.h"
 #include "gncEntry.h"
 #include "gncEntryP.h"
+#include "gnc-features.h"
 #include "gncJobP.h"
 #include "gncInvoice.h"
 #include "gncInvoiceP.h"
@@ -533,6 +534,12 @@ void gncInvoiceSetIsCreditNote (GncInvoice *invoice, gboolean credit_note)
                          credit_note ? 1 : 0);
     mark_invoice (invoice);
     gncInvoiceCommitEdit (invoice);
+
+    /* If this is a credit note, set a feature flag for it in the book
+     * This will prevent older GnuCash versions that don't support
+     * credit notes to open this file. */
+    if (credit_note)
+        gnc_features_set_used (gncInvoiceGetBook (invoice), GNC_FEATURE_CREDIT_NOTES);
 }
 
 void gncInvoiceSetCurrency (GncInvoice *invoice, gnc_commodity *currency)

src/gnome-utils/gnc-file.c

@@ -919,7 +919,7 @@ RESTART:
         /* test for unknown features. */
         if (!uh_oh)
         {
-            gchar *msg = test_unknown_features(new_session);
+            gchar *msg = gnc_features_test_unknown(qof_session_get_book (new_session));
 
             if (msg)
             {