app, libgimp, pdb, plug-ins: new gimp_resources_loaded() function.

And use the function in script-fu. While we want wrong resource names to
trigger WARNINGs in Script-Fu scripts and plug-ins (because these can be
considered as a bug), we don't want it to happen when the resource is
not loaded on purpose (mostly it means that we run GIMP with --no-data
or --no-fonts). This was happening in our own builds when running GIMP
through the in-build-gimp.py script and that was always very annoying.

Now in such a case, we will only output an INFO message on stderr (it's
still a good idea to warn about this, because if we imagined someone was
running a script non-interactively, which called one of these
procedures, they may have relied on the default value of some arguments.
Therefore they'd want to know about such a behavior change).

app/pdb/internal-procs.c

@@ -30,7 +30,7 @@
 #include "internal-procs.h"
 
 
-/* 785 procedures registered total */
+/* 786 procedures registered total */
 
 void
 internal_procs_init (GimpPDB *pdb)

app/pdb/resource-cmds.c

@@ -48,6 +48,38 @@
 #include "gimp-intl.h"
 
 
+static GimpValueArray *
+resources_loaded_invoker (GimpProcedure         *procedure,
+                          Gimp                  *gimp,
+                          GimpContext           *context,
+                          GimpProgress          *progress,
+                          const GimpValueArray  *args,
+                          GError               **error)
+{
+  gboolean success = TRUE;
+  GimpValueArray *return_vals;
+  const gchar *type_name;
+  gboolean loaded = FALSE;
+
+  type_name = g_value_get_string (gimp_value_array_index (args, 0));
+
+  if (success)
+    {
+      if (g_type_from_name (type_name) == GIMP_TYPE_FONT)
+        loaded = ! gimp->no_fonts;
+      else
+        loaded = ! gimp->no_data;
+    }
+
+  return_vals = gimp_procedure_get_return_values (procedure, success,
+                                                  error ? *error : NULL);
+
+  if (success)
+    g_value_set_boolean (gimp_value_array_index (return_vals, 1), loaded);
+
+  return return_vals;
+}
+
 static GimpValueArray *
 resource_get_by_name_invoker (GimpProcedure         *procedure,
                               Gimp                  *gimp,
@@ -510,6 +542,37 @@ register_resource_procs (GimpPDB *pdb)
 {
   GimpProcedure *procedure;
 
+  /*
+   * gimp-resources-loaded
+   */
+  procedure = gimp_procedure_new (resources_loaded_invoker, TRUE);
+  gimp_object_set_static_name (GIMP_OBJECT (procedure),
+                               "gimp-resources-loaded");
+  gimp_procedure_set_static_help (procedure,
+                                  "Returns whether resource of a given type were loaded.",
+                                  "Returns whether resources of a given type were loaded.\n"
+                                  "In particular, it would return FALSE if GIMP was started with `--no-data` or `--no-fonts` for fonts.",
+                                  NULL);
+  gimp_procedure_set_static_attribution (procedure,
+                                         "Jehan",
+                                         "Jehan",
+                                         "2026");
+  gimp_procedure_add_argument (procedure,
+                               gimp_param_spec_string ("type-name",
+                                                       "type name",
+                                                       "The name of the resource type e.g. GimpFont",
+                                                       FALSE, FALSE, TRUE,
+                                                       NULL,
+                                                       GIMP_PARAM_READWRITE));
+  gimp_procedure_add_return_value (procedure,
+                                   g_param_spec_boolean ("loaded",
+                                                         "loaded",
+                                                         "Whether resources of @type_name were loaded",
+                                                         FALSE,
+                                                         GIMP_PARAM_READWRITE));
+  gimp_pdb_register_procedure (pdb, procedure);
+  g_object_unref (procedure);
+
   /*
    * gimp-resource-get-by-name
    */

libgimp/gimp.def

@@ -1059,6 +1059,7 @@ EXPORTS
 	gimp_resource_rename
 	gimp_resource_select_new
 	gimp_resource_select_set
+	gimp_resources_loaded
 	gimp_selection_all
 	gimp_selection_border
 	gimp_selection_bounds

libgimp/gimpresource.c

@@ -273,6 +273,31 @@ gimp_resource_deserialize_create (GType     type,
   return GIMP_CONFIG (resource);;
 }
 
+
+/* Public functions */
+
+/**
+ * gimp_resources_loaded:
+ * @resource_type: The #GType of the resource.
+ *
+ * Returns whether the resource with the given @resource_type were
+ * loaded.
+ *
+ * In particular, it would return FALSE if GIMP was started with
+ * `--no-data` (or `--no-fonts` for fonts).
+ *
+ * Returns: Whether resources of @resource_type were loaded.
+ *
+ * Since: 3.2.4
+ **/
+gboolean
+gimp_resources_loaded (GType resource_type)
+{
+  g_return_val_if_fail (g_type_is_a (resource_type, GIMP_TYPE_RESOURCE), FALSE);
+
+  return _gimp_resources_loaded (g_type_name (resource_type));
+}
+
 /**
  * gimp_resource_get_id:
  * @resource: The resource.

libgimp/gimpresource.h

@@ -49,6 +49,8 @@ struct _GimpResourceClass
   void (*_gimp_reserved9) (void);
 };
 
+gboolean       gimp_resources_loaded     (GType         resource_type);
+
 gint32         gimp_resource_get_id      (GimpResource *resource);
 GimpResource * gimp_resource_get_by_id   (gint32        resource_id);
 GimpResource * gimp_resource_get_by_name (GType         resource_type,

libgimp/gimpresource_pdb.c

@@ -36,6 +36,44 @@
  **/
 
 
+/**
+ * _gimp_resources_loaded:
+ * @type_name: The name of the resource type e.g. GimpFont.
+ *
+ * Returns whether resource of a given type were loaded.
+ *
+ * Returns whether resources of a given type were loaded.
+ * In particular, it would return FALSE if GIMP was started with
+ * `--no-data` or `--no-fonts` for fonts.
+ *
+ * Returns: Whether resources of @type_name were loaded.
+ *
+ * Since: 3.2.4
+ **/
+gboolean
+_gimp_resources_loaded (const gchar *type_name)
+{
+  GimpValueArray *args;
+  GimpValueArray *return_vals;
+  gboolean loaded = FALSE;
+
+  args = gimp_value_array_new_from_types (NULL,
+                                          G_TYPE_STRING, type_name,
+                                          G_TYPE_NONE);
+
+  return_vals = _gimp_pdb_run_procedure_array (gimp_get_pdb (),
+                                               "gimp-resources-loaded",
+                                               args);
+  gimp_value_array_unref (args);
+
+  if (GIMP_VALUES_GET_ENUM (return_vals, 0) == GIMP_PDB_SUCCESS)
+    loaded = GIMP_VALUES_GET_BOOLEAN (return_vals, 1);
+
+  gimp_value_array_unref (return_vals);
+
+  return loaded;
+}
+
 /**
  * _gimp_resource_get_by_name:
  * @type_name: The name of the resource type e.g. GimpFont.

libgimp/gimpresource_pdb.h

@@ -32,6 +32,7 @@ G_BEGIN_DECLS
 /* For information look into the C source or the html documentation */
 
 
+G_GNUC_INTERNAL gboolean      _gimp_resources_loaded            (const gchar   *type_name);
 G_GNUC_INTERNAL GimpResource* _gimp_resource_get_by_name        (const gchar   *type_name,
                                                                  const gchar   *resource_name);
 G_GNUC_INTERNAL GimpResource* _gimp_resource_get_by_identifiers (const gchar   *type_name,

pdb/groups/resource.pdb

@@ -16,6 +16,41 @@
 
 # "Perlized" from C source by Manish Singh <yosh@gimp.org>
 
+sub resources_loaded {
+    $blurb = "Returns whether resource of a given type were loaded.";
+    $help  = <<HELP;
+Returns whether resources of a given type were loaded.
+
+In particular, it would return FALSE if GIMP was started with `--no-data`
+or `--no-fonts` for fonts.
+HELP
+
+    &jehan_pdb_misc('2026', '3.2.4');
+
+    $lib_private = 1;
+
+    @inargs = (
+        { name => 'type_name', type => 'string', non_empty => 1,
+          desc => 'The name of the resource type e.g. GimpFont' }
+    );
+
+    @outargs = (
+	{ name => 'loaded', type => 'boolean',
+	  desc => 'Whether resources of @type_name were loaded' }
+    );
+
+    %invoke = (
+        code => <<'CODE'
+{
+  if (g_type_from_name (type_name) == GIMP_TYPE_FONT)
+    loaded = ! gimp->no_fonts;
+  else
+    loaded = ! gimp->no_data;
+}
+CODE
+    );
+}
+
 sub resource_get_by_name {
     $blurb = "Returns a resource with the given name.";
     $help  = <<HELP;
@@ -497,7 +532,8 @@ CODE
               "gimppdberror.h"
               "gimp-intl.h");
 
-@procs = qw(resource_get_by_name
+@procs = qw(resources_loaded
+            resource_get_by_name
             resource_get_by_identifiers
             resource_id_is_valid
             resource_id_is_brush

plug-ins/script-fu/libscriptfu/script-fu-arg.c

@@ -311,7 +311,15 @@ script_fu_add_resource_arg (
            * later on, the fonts will likely have been loaded by then.
            */
           if (arg->default_value.sfa_resource.resource_type != GIMP_TYPE_FONT)
-            g_warning ("%s declared resource name is invalid %s", G_STRFUNC, declared_name_of_default);
+            {
+              if (gimp_resources_loaded (arg->default_value.sfa_resource.resource_type))
+                g_warning ("%s declared resource name is invalid %s", G_STRFUNC, declared_name_of_default);
+              else
+                g_printerr ("INFO: argument '%s' (value \"%s\") of procedure '%s' ignored "
+                            "because resources of type %s are not loaded.\n",
+                            name, declared_name_of_default, gimp_procedure_get_name (procedure),
+                            g_type_name (arg->default_value.sfa_resource.resource_type));
+            }
           script_fu_add_resource_arg_default_from_context (procedure, name, nick, blurb, func);
         }
       else