Bug 1518587: Move startup profile selection to nsToolkitProfileService. r=froydnj

Currently nsAppRunner is responsible for choosing or creating a profile to use
at startup. It then has to create a reset profile if necessary and lock the
selected profile directories. But these latter things are done in different
places of the selection code and done in different ways, sometimes we delay
while trying to get the lock, sometimes we don't.

This patch moves the profile selection part of the code to its own function so
that then we only have to have one place that does the profile reset and
locking logic.

It makes a lot of sense to have the selection code live in the profile service.
It can use information from the database load to help make the choices and it
also means that we can expose the profile selection code through xpcom allowing
it to be easily automatically tested. It will also be more important for future
patches for the dedicated profiles feature.

Differential Revision: https://phabricator.services.mozilla.com/D16116

--HG--
extra : moz-landing-system : lando

Author: Mossop

browser/components/migration/tests/marionette/test_refresh_firefox.py

@@ -541,7 +541,6 @@ def doReset(self):
           env.set("MOZ_MARIONETTE_PREF_STATE_ACROSS_RESTARTS", JSON.stringify(prefObj));
           env.set("MOZ_RESET_PROFILE_RESTART", "1");
           env.set("XRE_PROFILE_PATH", arguments[0]);
-          env.set("XRE_PROFILE_NAME", profileName);
         """, script_args=(self.marionette.instance.profile.profile, profileName,))
 
         profileLeafName = os.path.basename(os.path.normpath(

toolkit/profile/moz.build

@@ -6,6 +6,8 @@
 
 MOCHITEST_CHROME_MANIFESTS += ['test/chrome.ini']
 
+XPCSHELL_TESTS_MANIFESTS += ['xpcshell/xpcshell.ini']
+
 if CONFIG['ENABLE_TESTS']:
     DIRS += ['gtest']
 

toolkit/profile/nsIToolkitProfileService.idl

@@ -10,7 +10,7 @@ interface nsIFile;
 interface nsIToolkitProfile;
 interface nsIProfileLock;
 
-[scriptable, uuid(1947899b-f369-48fa-89da-f7c37bb1e6bc)]
+[scriptable, builtinclass, uuid(1947899b-f369-48fa-89da-f7c37bb1e6bc)]
 interface nsIToolkitProfileService : nsISupports
 {
     attribute boolean startWithLastProfile;
@@ -37,6 +37,28 @@ interface nsIToolkitProfileService : nsISupports
      */
     attribute nsIToolkitProfile defaultProfile;
 
+    /**
+     * Selects or creates a profile to use based on the profiles database, any
+     * environment variables and any command line arguments. Will not create
+     * a profile if aIsResetting is true. The profile is selected based on this
+     * order of preference:
+     * * Environment variables (set when restarting the application).
+     * * --profile command line argument.
+     * * --createprofile command line argument (this also causes the app to exit).
+     * * -p command line argument.
+     * * A new profile created if this is the first run of the application.
+     * * The default profile.
+     * aRootDir and aLocalDir are set to the data and local directories for the
+     * profile data. If a profile from the database was selected it will be
+     * returned in aProfile.
+     * This returns true if a new profile was created.
+     * This method is primarily for testing. It can be called only once.
+     */
+    bool selectStartupProfile(in Array<ACString> aArgv,
+                              in boolean aIsResetting,
+                              out nsIFile aRootDir, out nsIFile aLocalDir,
+                              out nsIToolkitProfile aProfile);
+
     /**
      * Get a profile by name. This is mainly for use by the -P
      * commandline flag.