279090 - When I query some interface then previous queried interface methods aren't removed

Status: RESOLVED INVALID

(Core :: XPConnect, defect)

Description

[alexander :surkov (:asurkov)]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.8a6) Gecko/20050111
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.8a6) Gecko/20050111

I query interface 'iface1' from some object. When I query interface 'iface2'
then methods of interface 'iface1' aren't removed from object.

In instance:
var doc=window.QueryInterface(Components.interfaces.nsIInterfaceRequestor).
		getInterface(Components.interfaces.nsIWebNavigation);

doc=doc.QueryInterface(Components.interfaces.nsIDocShell);

Variable 'doc' will have methods of interfaces 'nsIWebNavigation' and 'nsIDocShell'.

Reproducible: Always

Steps to Reproduce:

Comment 1

[alexander :surkov (:asurkov)]

Attachment: testcase

Comment 2

[David Bradley]

This behavior is intended and how XPConnect works. XPConnect flattens out the 
interfaces as they are QI'd. Is this causing some problem for you?

Comment 3

[alexander :surkov (:asurkov)]

No, I haven't any problem. When I worked with COM then I got used to it. I
expect begaviour of QueryInterface() in XPCOM will be like behaviour QI() in
COM. Is there the same behaviour when I work with XPCOM in C++?