View source for User:Jminta/Mail XPCOMUtils

Writing XPCOMUtils patches for Thunderbird is a great way to get beginning exposure to a specific area of the codebase.  This page provides a brief tutorial on how to go about writing one of these patches.

=== What is XPCOMUtils? ===
XPCOMUtils is a javascript module that can be included in any javascript file via <code>Components.utils.import</code>.  The module is only compiled once, meaning that putting repetitive code in a module can result in startup improvements.

Specifically, XPCOMUtils provides functions that simplify the registration process for XPCOM components.

=== How do I write the patch? ===
# Find a javascript component file (see list below).
# Import the XPCOMUtils module
# Replace any QueryInterface functions with XPCOMUtils.generateQI
# Remove any nsIFactory and nsIModule implementations
# Add in the appropriate fields to the component's prototype. (see [http://mxr.mozilla.org/seamonkey/source/js/src/xpconnect/loader/XPCOMUtils.jsm#54 this example])
# Replace the NSGetModule implementation

Then test your patch (rebuild Thunderbird and watch your console during startup to see that your component is registered), file a bug, attach it, and request a review.

Here is [https://bugzilla.mozilla.org/attachment.cgi?id=295317&action=diff an example patch.]

=== Which files need to be fixed? ===
Any javascript component file. Tentative list:
*[http://mxr.mozilla.org/seamonkey/source/mail/components/shell/nsSetDefaultMail.js nsSetDefaultMail.js] Fixed in [https://bugzilla.mozilla.org/show_bug.cgi?id=410727 bug 410727]
*[http://mxr.mozilla.org/seamonkey/source/mail/extensions/newsblog/js/newsblog.js newsblog.js]
*[http://mxr.mozilla.org/seamonkey/source/mail/components/search/nsSpotlightIntegration.js nsSpotlightIntegration.js]
*[http://mxr.mozilla.org/seamonkey/source/mail/components/phishing/nsPhishingProtectionApplication.js nsPhishingProtectionApplication.js]
*[http://mxr.mozilla.org/seamonkey/source/mail/components/nsMailDefaultHandler.js nsMailDefaultHandler.js]
*[http://mxr.mozilla.org/seamonkey/source/mailnews/extensions/smime/src/smime-service.js smime-service.js]
*[http://mxr.mozilla.org/seamonkey/source/mailnews/extensions/dsn/src/dsn-service.js dsn-service.js]
*[http://mxr.mozilla.org/seamonkey/source/mailnews/extensions/mdn/src/mdn-service.js mdn-service.js]
*[http://mxr.mozilla.org/seamonkey/source/mailnews/extensions/offline-startup/js/offlineStartup.js offlineStartup.js]
*[http://mxr.mozilla.org/seamonkey/source/mailnews/addrbook/src/nsAbLDAPAttributeMap.js nsAbLDAPAttributeMap.js]
*[http://mxr.mozilla.org/seamonkey/source/mailnews/addrbook/src/nsLDAPPrefsService.js nsLDAPPrefsService.js]