353812 - Add GetStringPref function to nsIPrefBranch

Status: RESOLVED DUPLICATE of bug 1345294

(Core :: Preferences: Backend, defect)

Description

[Jungshik Shin]

We don't have |uniCharPref| in nsIPrefBranch. Instead, to retrieve/set a non-ASCII string pref. value, we need to use {Get|Set}ComplexValue with nsISupportsString (for localized string pref, nsIPrefLocalized), but that's quite roundabout way. As a result, there are at least three utility functions for getting a string pref-value in UTF-16

http://lxr.mozilla.org/seamonkey/source/mailnews/base/util/nsMsgIdentity.cpp#166
http://lxr.mozilla.org/seamonkey/source/mailnews/base/util/nsMsgUtils.cpp#1074
http://lxr.mozilla.org/seamonkey/source/editor/ui/composer/content/editorUtilities.js#545

For javascript, this doesn't help much...

In addition, there are many misuses of |GetCharPref| where |GetUnicharPref|-equivalent (with GetComplexValue) should be used. (especially in  javascript code). Below is an example. Editor for view-source can have a path with non-ascii characters.

http://lxr.mozilla.org/seamonkey/source/toolkit/components/viewsource/content/viewSourceUtils.js#154

152       var prefs = Components.classes["@mozilla.org/preferences-service;1"]
153                             .getService(Components.interfaces.nsIPrefBranch);
154       var prefPath = prefs.getCharPref("view_source.editor.path");

Comment 1

[Christian :Biesinger (don't email me, ping me on IRC)]

well the editor should actually be stored as a complex nsIFile...

Comment 2

[Karsten Düsterloh]

nsMsgTagService also has its own complex->unichar routines:
http://lxr.mozilla.org/mozilla/source/mailnews/base/src/nsMsgTagService.cpp#425

Comment 3

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

The editor is now stored as nsIFile, see bug 789852.

Comment 4

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

I think that nsIPrefBranch.getUnicharPref() should work as nsIPrefBranch.getComplexValue() with nsIPrefLocalizedString. If we would separate getUnicharPref() and getLocalizedUnicharPref(), it would cause similar bug in the future. If we would have performance issue, we could improve it with checking whether the pref value indicated proeprties file or not.

nsIPrefBranch.getFilePref() must also be useful. However, I think that we don't need nsIPrefBranch.getRelativeFile() or something for nsIRelativeFilePref since there is no user of this.
http://mxr.mozilla.org/mozilla-central/search?string=nsIRelativeFilePref&filter=[Nn]sIRelativeFilePref

Comment 5

[Christian :Biesinger (don't email me, ping me on IRC)]

comm-central uses nsIRelativeFilePref, fyi.

http://mxr.mozilla.org/comm-central/search?string=nsIRelativeFilePref

Comment 6

[:Gavin Sharp [email: [e-mail]]]

GetStringPref seems like a better name.