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How to use observe method in fMBT
Best Python code snippet using fMBT_python
test_Preferences.js
Source:test_Preferences.js 
...156});157add_test(function test_observe_prefs_function() {158 let observed = false;159 let observer = function() { observed = !observed };160 Preferences.observe("test_observe_prefs_function", observer);161 Preferences.set("test_observe_prefs_function.subpref", "something");162 do_check_false(observed);163 Preferences.set("test_observe_prefs_function", "something");164 do_check_true(observed);165 Preferences.ignore("test_observe_prefs_function", observer);166 Preferences.set("test_observe_prefs_function", "something else");167 do_check_true(observed);168 // Clean up.169 Preferences.reset("test_observe_prefs_function");170 Preferences.reset("test_observe_prefs_function.subpref");171 run_next_test();172});173add_test(function test_observe_prefs_object() {174 let observer = {175 observed: false,176 observe() {177 this.observed = !this.observed;178 }179 };180 Preferences.observe("test_observe_prefs_object", observer.observe, observer);181 Preferences.set("test_observe_prefs_object.subpref", "something");182 do_check_false(observer.observed);183 Preferences.set("test_observe_prefs_object", "something");184 do_check_true(observer.observed);185 Preferences.ignore("test_observe_prefs_object", observer.observe, observer);186 Preferences.set("test_observe_prefs_object", "something else");187 do_check_true(observer.observed);188 // Clean up.189 Preferences.reset("test_observe_prefs_object");190 Preferences.reset("test_observe_prefs_object.subpref");191 run_next_test();192});193add_test(function test_observe_prefs_nsIObserver() {194 let observer = {195 observed: false,196 observe(subject, topic, data) {197 this.observed = !this.observed;198 do_check_true(subject instanceof Ci.nsIPrefBranch);199 do_check_eq(topic, "nsPref:changed");200 do_check_eq(data, "test_observe_prefs_nsIObserver");201 }202 };203 Preferences.observe("test_observe_prefs_nsIObserver", observer);204 Preferences.set("test_observe_prefs_nsIObserver.subpref", "something");205 Preferences.set("test_observe_prefs_nsIObserver", "something");206 do_check_true(observer.observed);207 Preferences.ignore("test_observe_prefs_nsIObserver", observer);208 Preferences.set("test_observe_prefs_nsIObserver", "something else");209 do_check_true(observer.observed);210 // Clean up.211 Preferences.reset("test_observe_prefs_nsIObserver");212 Preferences.reset("test_observe_prefs_nsIObserver.subpref");213 run_next_test();214});215// This should not need to be said, but *DO NOT DISABLE THIS TEST*.216//217// Existing consumers of the observer API depend on the observer only218// being triggered for the exact preference they are observing. This is219// expecially true for consumers of the function callback variant which220// passes the preference's new value but not its name.221add_test(function test_observe_exact_pref() {222 let observed = false;223 let observer = function() { observed = !observed };224 Preferences.observe("test_observe_exact_pref", observer);225 Preferences.set("test_observe_exact_pref.sub-pref", "something");226 do_check_false(observed);227 // Clean up.228 Preferences.ignore("test_observe_exact_pref", observer);229 Preferences.reset("test_observe_exact_pref.sub-pref");230 run_next_test();231});232add_test(function test_observe_value_of_set_pref() {233 let observer = function(newVal) { do_check_eq(newVal, "something") };234 Preferences.observe("test_observe_value_of_set_pref", observer);235 Preferences.set("test_observe_value_of_set_pref.subpref", "somethingelse");236 Preferences.set("test_observe_value_of_set_pref", "something");237 // Clean up.238 Preferences.ignore("test_observe_value_of_set_pref", observer);239 Preferences.reset("test_observe_value_of_set_pref");240 Preferences.reset("test_observe_value_of_set_pref.subpref");241 run_next_test();242});243add_test(function test_observe_value_of_reset_pref() {244 let observer = function(newVal) { do_check_true(typeof newVal == "undefined") };245 Preferences.set("test_observe_value_of_reset_pref", "something");246 Preferences.observe("test_observe_value_of_reset_pref", observer);247 Preferences.reset("test_observe_value_of_reset_pref");248 // Clean up.249 Preferences.ignore("test_observe_value_of_reset_pref", observer);250 run_next_test();251});252add_test(function test_has_pref() {253 do_check_false(Preferences.has("test_has_pref"));254 Preferences.set("test_has_pref", "foo");255 do_check_true(Preferences.has("test_has_pref"));256 Preferences.set("test_has_pref.foo", "foo");257 Preferences.set("test_has_pref.bar", "bar");258 let [hasFoo, hasBar, hasBaz] = Preferences.has(["test_has_pref.foo",259 "test_has_pref.bar",260 "test_has_pref.baz"]);...
observe.js
Source:observe.js
1// XXX maybe move these into another ObserveHelpers package or something2// _CachingChangeObserver is an object which receives observeChanges callbacks3// and keeps a cache of the current cursor state up to date in self.docs. Users4// of this class should read the docs field but not modify it. You should pass5// the "applyChange" field as the callbacks to the underlying observeChanges6// call. Optionally, you can specify your own observeChanges callbacks which are7// invoked immediately before the docs field is updated; this object is made8// available as `this` to those callbacks.9LocalCollection._CachingChangeObserver = function (options) {10 var self = this;11 options = options || {};12 var orderedFromCallbacks = options.callbacks &&13 LocalCollection._observeChangesCallbacksAreOrdered(options.callbacks);14 if (_.has(options, 'ordered')) {15 self.ordered = options.ordered;16 if (options.callbacks && options.ordered !== orderedFromCallbacks)17 throw Error("ordered option doesn't match callbacks");18 } else if (options.callbacks) {19 self.ordered = orderedFromCallbacks;20 } else {21 throw Error("must provide ordered or callbacks");22 }23 var callbacks = options.callbacks || {};24 if (self.ordered) {25 self.docs = new OrderedDict(LocalCollection._idStringify);26 self.applyChange = {27 addedBefore: function (id, fields, before) {28 var doc = EJSON.clone(fields);29 doc._id = id;30 callbacks.addedBefore && callbacks.addedBefore.call(31 self, id, fields, before);32 // This line triggers if we provide added with movedBefore.33 callbacks.added && callbacks.added.call(self, id, fields);34 // XXX could `before` be a falsy ID? Technically35 // idStringify seems to allow for them -- though36 // OrderedDict won't call stringify on a falsy arg.37 self.docs.putBefore(id, doc, before || null);38 },39 movedBefore: function (id, before) {40 var doc = self.docs.get(id);41 callbacks.movedBefore && callbacks.movedBefore.call(self, id, before);42 self.docs.moveBefore(id, before || null);43 }44 };45 } else {46 self.docs = new LocalCollection._IdMap;47 self.applyChange = {48 added: function (id, fields) {49 var doc = EJSON.clone(fields);50 callbacks.added && callbacks.added.call(self, id, fields);51 doc._id = id;52 self.docs.set(id, doc);53 }54 };55 }56 // The methods in _IdMap and OrderedDict used by these callbacks are57 // identical.58 self.applyChange.changed = function (id, fields) {59 var doc = self.docs.get(id);60 if (!doc)61 throw new Error("Unknown id for changed: " + id);62 callbacks.changed && callbacks.changed.call(63 self, id, EJSON.clone(fields));64 LocalCollection._applyChanges(doc, fields);65 };66 self.applyChange.removed = function (id) {67 callbacks.removed && callbacks.removed.call(self, id);68 self.docs.remove(id);69 };70};71LocalCollection._observeFromObserveChanges = function (cursor, observeCallbacks) {72 var transform = cursor.getTransform() || function (doc) {return doc;};73 var suppressed = !!observeCallbacks._suppress_initial;74 var observeChangesCallbacks;75 if (LocalCollection._observeCallbacksAreOrdered(observeCallbacks)) {76 // The "_no_indices" option sets all index arguments to -1 and skips the77 // linear scans required to generate them. This lets observers that don't78 // need absolute indices benefit from the other features of this API --79 // relative order, transforms, and applyChanges -- without the speed hit.80 var indices = !observeCallbacks._no_indices;81 observeChangesCallbacks = {82 addedBefore: function (id, fields, before) {83 var self = this;84 if (suppressed || !(observeCallbacks.addedAt || observeCallbacks.added))85 return;86 var doc = transform(_.extend(fields, {_id: id}));87 if (observeCallbacks.addedAt) {88 var index = indices89 ? (before ? self.docs.indexOf(before) : self.docs.size()) : -1;90 observeCallbacks.addedAt(doc, index, before);91 } else {92 observeCallbacks.added(doc);93 }94 },95 changed: function (id, fields) {96 var self = this;97 if (!(observeCallbacks.changedAt || observeCallbacks.changed))98 return;99 var doc = EJSON.clone(self.docs.get(id));100 if (!doc)101 throw new Error("Unknown id for changed: " + id);102 var oldDoc = transform(EJSON.clone(doc));103 LocalCollection._applyChanges(doc, fields);104 doc = transform(doc);105 if (observeCallbacks.changedAt) {106 var index = indices ? self.docs.indexOf(id) : -1;107 observeCallbacks.changedAt(doc, oldDoc, index);108 } else {109 observeCallbacks.changed(doc, oldDoc);110 }111 },112 movedBefore: function (id, before) {113 var self = this;114 if (!observeCallbacks.movedTo)115 return;116 var from = indices ? self.docs.indexOf(id) : -1;117 var to = indices118 ? (before ? self.docs.indexOf(before) : self.docs.size()) : -1;119 // When not moving backwards, adjust for the fact that removing the120 // document slides everything back one slot.121 if (to > from)122 --to;123 observeCallbacks.movedTo(transform(EJSON.clone(self.docs.get(id))),124 from, to, before || null);125 },126 removed: function (id) {127 var self = this;128 if (!(observeCallbacks.removedAt || observeCallbacks.removed))129 return;130 // technically maybe there should be an EJSON.clone here, but it's about131 // to be removed from self.docs!132 var doc = transform(self.docs.get(id));133 if (observeCallbacks.removedAt) {134 var index = indices ? self.docs.indexOf(id) : -1;135 observeCallbacks.removedAt(doc, index);136 } else {137 observeCallbacks.removed(doc);138 }139 }140 };141 } else {142 observeChangesCallbacks = {143 added: function (id, fields) {144 if (!suppressed && observeCallbacks.added) {145 var doc = _.extend(fields, {_id: id});146 observeCallbacks.added(transform(doc));147 }148 },149 changed: function (id, fields) {150 var self = this;151 if (observeCallbacks.changed) {152 var oldDoc = self.docs.get(id);153 var doc = EJSON.clone(oldDoc);154 LocalCollection._applyChanges(doc, fields);155 observeCallbacks.changed(transform(doc),156 transform(EJSON.clone(oldDoc)));157 }158 },159 removed: function (id) {160 var self = this;161 if (observeCallbacks.removed) {162 observeCallbacks.removed(transform(self.docs.get(id)));163 }164 }165 };166 }167 var changeObserver = new LocalCollection._CachingChangeObserver(168 {callbacks: observeChangesCallbacks});169 var handle = cursor.observeChanges(changeObserver.applyChange);170 suppressed = false;171 return handle;...
observableset.js
Source:observableset.js
...61 return false;62 }63 this.observers_.push(observer);64 goog.array.forEach(this.observables_, function(o) {65 o.observe(observer);66 });67 return true;68};69/**70 * Removes an observer from the set. The observer will be removed from71 * all observables in the set. Does nothing if the observer is not in72 * the set.73 * @param {!goog.labs.observe.Observer} observer The observer to remove.74 * @return {boolean} Whether the observer is actually removed.75 */76goog.labs.observe.ObservableSet.prototype.removeObserver = function(observer) {77 // Check that the observer exists before removing.78 var removed = goog.array.removeIf(this.observers_, goog.partial(79 goog.labs.observe.Observer.equals, observer));80 if (removed) {81 goog.array.forEach(this.observables_, function(o) {82 o.unobserve(observer);83 });84 }85 return removed;86};87/**88 * Removes all registered observers.89 */90goog.labs.observe.ObservableSet.prototype.removeAllObservers = function() {91 this.unregisterAll_();92 this.observers_.length = 0;93};94/**95 * Adds an observable to the set. All previously added and future96 * observers will be added to the new observable as well.97 *98 * The observable will not be added if it is already registered in the99 * set.100 *101 * @param {!goog.labs.observe.Observable} observable The observable to add.102 * @return {boolean} Whether the observable is actually added.103 */104goog.labs.observe.ObservableSet.prototype.addObservable = function(observable) {105 if (goog.array.contains(this.observables_, observable)) {106 return false;107 }108 this.observables_.push(observable);109 goog.array.forEach(this.observers_, function(observer) {110 observable.observe(observer);111 });112 return true;113};114/**115 * Removes an observable from the set. All observers registered on the116 * set will be removed from the observable as well.117 * @param {!goog.labs.observe.Observable} observable The observable to remove.118 * @return {boolean} Whether the observable is actually removed.119 */120goog.labs.observe.ObservableSet.prototype.removeObservable = function(121 observable) {122 var removed = goog.array.remove(this.observables_, observable);123 if (removed) {124 goog.array.forEach(this.observers_, function(observer) {125 observable.unobserve(observer);126 });127 }128 return removed;129};130/**131 * Removes all registered observables.132 */133goog.labs.observe.ObservableSet.prototype.removeAllObservables = function() {134 this.unregisterAll_();135 this.observables_.length = 0;136};137/**138 * Removes all registered observations and observables.139 */140goog.labs.observe.ObservableSet.prototype.removeAll = function() {141 this.removeAllObservers();142 this.observables_.length = 0;143};144/**145 * Unregisters all registered observers from all registered observables.146 * @private147 */148goog.labs.observe.ObservableSet.prototype.unregisterAll_ = function() {149 goog.array.forEach(this.observers_, function(observer) {150 goog.array.forEach(this.observables_, function(o) {151 o.unobserve(observer);152 });153 }, this);...
observationset.js
Source:observationset.js
...50 * @return {boolean} True if the observer is successfully registered.51 */52goog.labs.observe.ObservationSet.prototype.observe = function(53 observable, observer) {54 var success = observable.observe(observer);55 if (success) {56 this.storedObservations_.push(57 new goog.labs.observe.ObservationSet.Observation_(58 observable, observer));59 }60 return success;61};62/**63 * Observes the given function on the observable.64 * @param {!goog.labs.observe.Observable} observable The observable to65 * observe on.66 * @param {function(!goog.labs.observe.Notice)} fn The handler function.67 * @param {!Object=} opt_scope Optional scope.68 * @return {goog.labs.observe.Observer} The registered observer object.69 * If the observer is not successfully registered, this will be null.70 */71goog.labs.observe.ObservationSet.prototype.observeWithFunction = function(72 observable, fn, opt_scope) {73 var observer = goog.labs.observe.Observer.fromFunction(74 fn, opt_scope || this.defaultScope_);75 if (this.observe(observable, observer)) {76 return observer;77 }78 return null;79};80/**81 * Unobserves the given observer from the observable.82 * @param {!goog.labs.observe.Observable} observable The observable to83 * unobserve from.84 * @param {!goog.labs.observe.Observer} observer The observer.85 * @return {boolean} True if the observer is successfully removed.86 */87goog.labs.observe.ObservationSet.prototype.unobserve = function(88 observable, observer) {89 var removed = goog.array.removeIf(90 this.storedObservations_, function(o) {91 return o.observable == observable &&92 goog.labs.observe.Observer.equals(o.observer, observer);93 });94 if (removed) {95 observable.unobserve(observer);96 }97 return removed;98};99/**100 * Unobserves the given function from the observable.101 * @param {!goog.labs.observe.Observable} observable The observable to102 * unobserve from.103 * @param {function(!goog.labs.observe.Notice)} fn The handler function.104 * @param {!Object=} opt_scope Optional scope.105 * @return {boolean} True if the observer is successfully removed.106 */107goog.labs.observe.ObservationSet.prototype.unobserveWithFunction = function(108 observable, fn, opt_scope) {109 var observer = goog.labs.observe.Observer.fromFunction(110 fn, opt_scope || this.defaultScope_);111 return this.unobserve(observable, observer);112};113/**114 * Removes all observations registered through this set.115 */116goog.labs.observe.ObservationSet.prototype.removeAll = function() {117 goog.array.forEach(this.storedObservations_, function(observation) {118 var observable = observation.observable;119 var observer = observation.observer;120 observable.unobserve(observer);121 });122};123/**124 * A representation of an observation, which is defined uniquely by125 * the observable and observer.126 * @param {!goog.labs.observe.Observable} observable The observable.127 * @param {!goog.labs.observe.Observer} observer The observer.128 * @constructor129 * @private130 */131goog.labs.observe.ObservationSet.Observation_ = function(132 observable, observer) {133 this.observable = observable;134 this.observer = observer;...
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