feat: add isRootZone api

For now I'm not documenting this api.

I think it generally useful and harmless enough that it could be a
public api.

Author: IgorMinar

dist/zone-microtask.js

@@ -27,7 +27,7 @@ browserPatch.apply();
 function Zone(parentZone, data) {
   var zone = (arguments.length) ? Object.create(parentZone) : this;
 
-  zone.parent = parentZone;
+  zone.parent = parentZone || null;
 
   Object.keys(data || {}).forEach(function(property) {
 
@@ -98,6 +98,10 @@ Zone.prototype = {
     });
   },
 
+  isRootZone: function() {
+    return this.parent === null;
+  },
+
   run: function run (fn, applyTo, applyWith) {
     applyWith = applyWith || [];
 

dist/zone-microtask.min.js

@@ -22,7 +22,7 @@ browserPatch.apply();
 function Zone(parentZone, data) {
   var zone = (arguments.length) ? Object.create(parentZone) : this;
 
-  zone.parent = parentZone;
+  zone.parent = parentZone || null;
 
   Object.keys(data || {}).forEach(function(property) {
 
@@ -93,6 +93,10 @@ Zone.prototype = {
     });
   },
 
+  isRootZone: function() {
+    return this.parent === null;
+  },
+
   run: function run (fn, applyTo, applyWith) {
     applyWith = applyWith || [];
 

dist/zone.js

@@ -3,7 +3,7 @@
 function Zone(parentZone, data) {
   var zone = (arguments.length) ? Object.create(parentZone) : this;
 
-  zone.parent = parentZone;
+  zone.parent = parentZone || null;
 
   Object.keys(data || {}).forEach(function(property) {
 
@@ -74,6 +74,10 @@ Zone.prototype = {
     });
   },
 
+  isRootZone: function() {
+    return this.parent === null;
+  },
+
   run: function run (fn, applyTo, applyWith) {
     applyWith = applyWith || [];
 

dist/zone.min.js

@@ -129,6 +129,26 @@ describe('Zone', function () {
   });
 
 
+  describe('isRootZone', function() {
+
+    it('should return true for root zone', function() {
+      expect(zone.isRootZone()).toBe(true);
+    });
+
+
+    it('should return false for non-root zone', function() {
+      var executed = false;
+
+      zone.fork().run(function() {
+        executed = true;
+        expect(zone.isRootZone()).toBe(false);
+      });
+
+      expect(executed).toBe(true);
+    });
+  });
+
+
   describe('fork', function () {
     it('should fork deep copy', function () {
       var protoZone = { too: { deep: true } },