1859980 - Use createLocalSubfolder where possible in tests

Status: RESOLVED FIXED

(MailNews Core :: General, task)

Description

[Geoff Lankow (:darktrojan)]

We have a pattern, especially in tests, of

1. getting an nsIMsgFolder
2. QIing it to nsIMsgLocalMailFolder
3. calling createLocalSubfolder
4. QIing that folder to nsIMsgLocalMailFolder

so we can create sub-sub-folders or add messages. It'd be less of a mess if step 4 was unnecessary, since we know from steps 2 and 3 it must be a local folder.

Comment 1

[Geoff Lankow (:darktrojan)]

Attachment: WIP: Bug 1859980 - Make createLocalSubfolder return nsIMsgLocalMailFolder not nsIMsgFolder. r=#thunderbird-reviewers

Comment 2

[Geoff Lankow (:darktrojan)]

Weirdly, although the two interfaces aren't related, the returned folder is already QIed to nsIMsgFolder so using the properties of that interface just works. There's some voodoo going on there I don't quite understand, but it makes life easier.

Comment 3

[Geoff Lankow (:darktrojan)]

I think I might abandon this idea. While it makes mochitests tidier to write (because of comment 2), in xpcshell tests that doesn't apply and folders have to be converted back to nsIMsgFolder all over the place. If we have to do a whole lot of converting, it should be from the more general interface to the more specific one.

Comment 4

[Geoff Lankow (:darktrojan)]

Attachment: Bug 1859980 - Use createLocalSubfolder where possible in tests. r=#thunderbird-reviewers

This is a less-ugly pattern, even if it is longer because of all the QueryInterface-ing.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/comm-central/rev/a342b551ba91
Use createLocalSubfolder where possible in tests. r=leftmostcat