michael@0: const Cc = Components.classes;
michael@0: const Ci = Components.interfaces;
michael@0: const Cu = Components.utils;
michael@0: 
michael@0: Cu.import("resource://gre/modules/Services.jsm");
michael@0: Cu.import("resource://gre/modules/XPCOMUtils.jsm");
michael@0: 
michael@0: function shouldHaveChanged(a, b)
michael@0: {
michael@0:   if (a.length != b.length) {
michael@0:     throw Error("TEST-UNEXPECTED-FAIL: telemetry count array size changed");
michael@0:   }
michael@0: 
michael@0:   for (let i = 0; i < a.length; ++i) {
michael@0:     if (a[i] == b[i]) {
michael@0:       continue;
michael@0:     }
michael@0:     return; // something was different, that's all that matters
michael@0:   }
michael@0:   throw Error("TEST-UNEXPECTED-FAIL: telemetry data didn't change");
michael@0: }
michael@0: 
michael@0: function TestStartupCacheTelemetry() { }
michael@0: 
michael@0: TestStartupCacheTelemetry.prototype = {
michael@0:   classID: Components.ID("{73cbeffd-d6c7-42f0-aaf3-f176430dcfc8}"),
michael@0:   QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver]),
michael@0: 
michael@0:   saveInitial: function() {
michael@0:     let t = Services.telemetry;
michael@0:     this._age = t.getHistogramById("STARTUP_CACHE_AGE_HOURS").snapshot.counts;
michael@0:     this._invalid = t.getHistogramById("STARTUP_CACHE_INVALID").snapshot.counts;
michael@0:   },
michael@0: 
michael@0:   checkFinal: function() {
michael@0:     let t = Services.telemetry;
michael@0:     let newAge = t.getHistogramById("STARTUP_CACHE_AGE_HOURS").snapshot.counts;
michael@0:     shouldHaveChanged(this._age, newAge);
michael@0: 
michael@0:     let newInvalid = t.getHistogramById("STARTUP_CACHE_INVALID").snapshot.counts;
michael@0:     shouldHaveChanged(this._invalid, newInvalid);
michael@0:   },
michael@0: 
michael@0:   observe: function(subject, topic, data) {
michael@0:     switch (topic) {
michael@0:     case "save-initial":
michael@0:       this.saveInitial();
michael@0:       break;
michael@0: 
michael@0:     case "check-final":
michael@0:       this.checkFinal();
michael@0:       break;
michael@0: 
michael@0:     default:
michael@0:       throw Error("BADDOG, NO MILKBONE FOR YOU");
michael@0:     }
michael@0:   },
michael@0: };
michael@0: 
michael@0: this.NSGetFactory = XPCOMUtils.generateNSGetFactory([TestStartupCacheTelemetry]);