refactor(renderer): set first child to every NgElement

sis0k0 · sis0k0 · commit 4c8dd799f0cc · 2017-08-16T14:58:26.000+03:00
diff --git a/nativescript-angular/element-registry.ts b/nativescript-angular/element-registry.ts
@@ -5,13 +5,14 @@ export type NgView = (View & ViewExtensions);
 export type NgElement = NgView | InvisibleNode;
 
 export interface ViewExtensions {
+    meta: ViewClassMeta;
     nodeType: number;
     nodeName: string;
     templateParent: NgView;
     nextSibling: NgElement;
+    firstChild: NgElement;
     lastChild: NgElement;
     ngCssClasses: Map<string, boolean>;
-    meta: ViewClassMeta;
 }
 
 export interface ElementReference {
@@ -25,13 +26,13 @@ export interface ViewClass {
 
 export abstract class InvisibleNode extends View implements ViewExtensions {
     meta: { skipAddToDom: boolean };
-    templateParent: NgView;
     nodeType: number;
     nodeName: string;
-    ngCssClasses: Map<string, boolean>;
-    previousSibling: NgElement;
+    templateParent: NgView;
     nextSibling: NgElement;
+    firstChild: NgElement;
     lastChild: NgElement;
+    ngCssClasses: Map<string, boolean>;
 
     constructor() {
         super();
diff --git a/nativescript-angular/view-util.ts b/nativescript-angular/view-util.ts
@@ -54,7 +54,12 @@ export class ViewUtil {
         this.isAndroid = device.os === platformNames.android;
     }
 
-    public insertChild(parent: NgView, child: NgElement, previous?: NgElement, next?: NgElement) {
+    public insertChild(
+        parent: NgView,
+        child: NgElement,
+        previous: NgElement = parent.lastChild,
+        next?: NgElement
+    ) {
         if (!parent) {
             return;
         }
@@ -68,23 +73,25 @@ export class ViewUtil {
         }
     }
 
-    private addToQueue(parent: NgElement, child: NgElement, previous: NgElement, next: NgElement) {
+    private addToQueue(
+        parent: NgElement,
+        child: NgElement,
+        previous: NgElement,
+        next: NgElement
+    ): void {
+        if (previous) {
+            previous.nextSibling = child;
+        } else {
+            parent.firstChild = child;
+        }
+
         if (next) {
-            this.insertBetween(child, previous, next);
+            child.nextSibling = next;
         } else {
             this.appendToQueue(parent, child);
         }
     }
 
-    private insertBetween(
-        view: NgElement,
-        previous: NgElement,
-        next: NgElement
-    ): void {
-        previous.nextSibling = view;
-        view.nextSibling = next;
-    }
-
     private appendToQueue(parent: NgElement, view: NgElement) {
         if (parent.lastChild) {
             parent.lastChild.nextSibling = view;
@@ -133,35 +140,43 @@ export class ViewUtil {
             this.removeLayoutChild(parent, child);
         } else if (isContentView(parent) && parent.content === child) {
             parent.content = null;
+            parent.lastChild = null;
+            parent.firstChild = null;
         } else if (isView(parent)) {
             parent._removeView(child);
         }
     }
 
     private removeLayoutChild(parent: NgLayoutBase, child: NgView): void {
         const index = parent.getChildIndex(child);
+        this.removeFromQueue(parent, child, index);
         if (index === -1) {
             return;
         }
 
-        this.removeFromQueue(parent, child, index);
         parent.removeChild(child);
     }
 
     private removeFromQueue(parent: NgLayoutBase, child: NgView, index: number) {
-        let previous = parent.getChildAt(index - 1) as NgElement;
-        if (!previous) {
-            return;
+        if (parent.firstChild === child) {
+            parent.firstChild = child.nextSibling;
+        }
+
+        let previous = (parent.getChildAt(index - 1) || parent.firstChild) as NgElement;
+        if (parent.lastChild === child) {
+            parent.lastChild = previous;
         }
 
         // since detached elements are not added to the visual tree,
         // we need to find the actual previous sibling of the view,
-        // which may be an invisible node
-        while (previous && previous !== child && isDetachedElement(previous.nextSibling)) {
+        // which may as well be an invisible node
+        while ( previous && previous !== child && isDetachedElement(previous.nextSibling)) {
             previous = previous.nextSibling;
         }
 
-        previous.nextSibling = child.nextSibling;
+        if (previous) {
+            previous.nextSibling = child.nextSibling;
+        }
     }
 
     public getChildIndex(parent: any, child: NgView) {
diff --git a/tests/app/tests/property-sets.ts b/tests/app/tests/property-sets.ts
@@ -13,13 +13,13 @@ import {device, platformNames} from "platform";
 import {createDevice} from "./test-utils";
 
 class TestView extends View implements ViewExtensions {
-    public previousSibling: NgElement;
-    public nextSibling: NgElement;
-    public lastChild: NgElement;
-    public nodeName: string = "TestView";
+    public meta: ViewClassMeta = { skipAddToDom: false };
     public nodeType: number = 1;
+    public nodeName: string = "TestView";
     public templateParent: NgView = null;
-    public meta: ViewClassMeta = { skipAddToDom: false };
+    public nextSibling: NgElement;
+    public firstChild: NgElement;
+    public lastChild: NgElement;
     public ngCssClasses: Map<string, boolean> = new Map<string, boolean>();
 
     public stringValue: string = "";
