a #GtkSourceView
the location where @ch is to be inserted
modifier state for the insertion
the keyval pressed such as [const@Gdk.KEY_Return]
%TRUE if indentation should be automatically triggered; otherwise %FALSE and no indentation will be performed.
This function is used to determine if a key pressed should cause the indenter to automatically indent.
The default implementation of this virtual method will check to see if @keyval is [const@Gdk.KEY_Return] or [const@Gdk.KEY_KP_Enter] and @state does not have %GDK_SHIFT_MASK set. This is to allow the user to avoid indentation when Shift+Return is pressed. Other indenters may want to copy this behavior to provide a consistent experience to users.