720419 - nsIPrefBranch.resetBranch: Either remove or implement

Status: RESOLVED FIXED

(Core :: Preferences: Backend, enhancement)

Description

[Alex Vincent [:WeirdAl]]

/* void resetBranch (in string startingAt); */
NS_IMETHODIMP nsPrefBranch::ResetBranch(const char *aStartingAt)
{
  return NS_ERROR_NOT_IMPLEMENTED;
}

It's been this way for years:  a method defined in IDL but never, ever implemented.  We need to do something about that.

Comment 1

[Thomas D. (:thomas8)]

Ping? Still not implemented?

Also note that according to documentation, it's resetBranch (with lower-case r).

https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIPrefBranch#resetBranch%28%29

Workaround for resetting a single pref:
https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM/Reference/Interface/nsIPrefBranch#clearUserPref%28%29

Comment 2

[Marco Castelluccio [:marco]]

If we had this method, we could remove the `resetBranch` custom implementation from Preferences.jsm.

Comment 3

[Lina Butler [:lina]]

We're removing Preferences.jsm from Sync over in bug 1406475, and use `resetBranch` several times in the tests.

Comment 4

[Lina Butler [:lina]]

Attachment: Bug 720419 - Implement `nsIPrefBranch.resetBranch`. r?njn

Comment 5

[Lina Butler [:lina]]

:kmag's thorough review comment suggests we want to move to a world where we reset individual prefs, not whole branches. I'll keep the bug open in case someone would like to pursue that, but I'm not planning to take this over the line, sorry.

Comment 6

[Marco Castelluccio [:marco]]

Attachment: Bug 720419 - Remove nsIPrefBranch::ResetBranch. r=KrisWright

Make it so callers need to explicitly iterate through prefs using getChildList
when they want to reset an entire branch, to avoid the footgun of resetting
unintended prefs when using resetBranch for clearing a single pref.
See also https://phabricator.services.mozilla.com/D11381#357618.

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/1c7929ef20d2
Remove nsIPrefBranch::ResetBranch. r=KrisWright

Comment 8

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/1c7929ef20d2