[gimp/wip/Jehan/classy-GIMP: 29/64] libgimp: allow object GParamSpec for GimpItem and child classes.

[Jehan <jehanp src gnome org>]

commit b709e157b4a4be8cd04952775c9d58a76a2df2b8
Author: Jehan <jehan girinstud io>
Date:   Tue Aug 13 18:00:25 2019 +0200

    libgimp: allow object GParamSpec for GimpItem and child classes.

 libgimp/gimpgpparams-body.c | 18 ++++++++++++++++++
 libgimp/gimpprocedure.c     | 18 +++++++++++++++++-
 2 files changed, 35 insertions(+), 1 deletion(-)
---
diff --git a/libgimp/gimpgpparams-body.c b/libgimp/gimpgpparams-body.c
index 457b1ecca2..4af66964db 100644
--- a/libgimp/gimpgpparams-body.c
+++ b/libgimp/gimpgpparams-body.c
@@ -188,6 +188,24 @@ _gimp_param_spec_to_gp_param_def (GParamSpec *pspec,
           param_def->param_def_type = GP_PARAM_DEF_TYPE_ID;
           param_def->meta.m_id.none_ok = TRUE;
         }
+      else if (g_strcmp0 (g_type_name (pspec->value_type), "GimpItem") == 0)
+        {
+          param_def->type_name = "GimpParamItemID";
+          param_def->param_def_type = GP_PARAM_DEF_TYPE_ID;
+          param_def->meta.m_id.none_ok = TRUE;
+        }
+      else if (g_strcmp0 (g_type_name (pspec->value_type), "GimpDrawable") == 0)
+        {
+          param_def->type_name = "GimpParamDrawableID";
+          param_def->param_def_type = GP_PARAM_DEF_TYPE_ID;
+          param_def->meta.m_id.none_ok = TRUE;
+        }
+      else if (g_strcmp0 (g_type_name (pspec->value_type), "GimpLayer") == 0)
+        {
+          param_def->type_name = "GimpParamLayerID";
+          param_def->param_def_type = GP_PARAM_DEF_TYPE_ID;
+          param_def->meta.m_id.none_ok = TRUE;
+        }
     }
 }
 
diff --git a/libgimp/gimpprocedure.c b/libgimp/gimpprocedure.c
index cd7318fd56..b6c620cb98 100644
--- a/libgimp/gimpprocedure.c
+++ b/libgimp/gimpprocedure.c
@@ -1425,7 +1425,7 @@ gimp_procedure_validate_args (GimpProcedure   *procedure,
       GType       arg_type  = G_VALUE_TYPE (arg);
       GType       spec_type = G_PARAM_SPEC_VALUE_TYPE (pspec);
 
-      /* As a special case, validation can transform IDs into their
+      /* As special cases, validation can transform IDs into their
        * respective object.
        */
       if (arg_type == GIMP_TYPE_IMAGE_ID &&
@@ -1440,6 +1440,22 @@ gimp_procedure_validate_args (GimpProcedure   *procedure,
           gimp_value_array_insert (args, i, &value);
           g_value_unset (&value);
         }
+      else if ((arg_type == GIMP_TYPE_ITEM_ID &&
+                spec_type == GIMP_TYPE_ITEM)     ||
+               (arg_type == GIMP_TYPE_DRAWABLE_ID &&
+                spec_type == GIMP_TYPE_DRAWABLE) ||
+               (arg_type == GIMP_TYPE_LAYER_ID &&
+                spec_type == GIMP_TYPE_LAYER))
+        {
+          GValue    value = G_VALUE_INIT;
+          GimpItem *item = gimp_item_new_by_id (g_value_get_int (arg));
+
+          g_value_init (&value, spec_type);
+          g_value_take_object (&value, item);
+          gimp_value_array_remove (args, i);
+          gimp_value_array_insert (args, i, &value);
+          g_value_unset (&value);
+        }
       else if (arg_type != spec_type)
         {
           if (return_vals)