Gtk-3.0.gir: TreeModel.get_iter argument iter should be direction:inout

[Rumpeltux]

Same for Gtk-2.0.gir

The get_iter method is overriden by models to return a custom iter. The GtkTreeIter is initialised by the caller and passed to the callee who will fill in the user_data attribute.
Since the direction is set to "out", the param cannot be passed to the callee (e.g. using pygobject).
This makes it impossible to implement custom TreeModels with pygobject.
A fix will be to change the direction to "in" so that the argument gets passed to the callee ("inout" seems not to work :/).

      <field name="get_iter">
        <callback name="get_iter">
          <return-value transfer-ownership="none">
            <doc xml:whitespace="preserve">%TRUE, if @iter was set</doc>
            <type name="gboolean" c:type="gboolean"/>
          </return-value>
          <parameters>
            <parameter name="tree_model" transfer-ownership="none">
              <type name="TreeModel" c:type="GtkTreeModel*"/>
            </parameter>
            <parameter name="iter"
                       direction="in"
                       caller-allocates="1"
                       transfer-ownership="none">
              <doc xml:whitespace="preserve">the uninitialized #GtkTreeIter</doc>
              <type name="TreeIter" c:type="GtkTreeIter*"/>
            </parameter>
            <parameter name="path" transfer-ownership="none">
              <doc xml:whitespace="preserve">the #GtkTreePath</doc>
              <type name="TreePath" c:type="GtkTreePath*"/>
            </parameter>
          </parameters>
        </callback>
      </field>

As a sidenote: What I do not understand though is how the handling of the return value happens. Apparently a tuple is expected with the first argument being the boolean return value and the second argument seems to be copied to the iter->stamp field (the first field of the struct). However, it does not seem possible to set the other struct's fields.

When returning anything else than a tuple, the following error is raised (which is ok though, because the calling convention requires to return a tuple there):
ERROR:/build/buildd/pygobject-3.2.2/gi/pygi-closure.c:317:_pygi_closure_set_out_arguments: code should not be reached

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.