wip: try to create new root fiber instead of reusing it

This reverts commit 989b0d6709.

src/component/component_node.ts

@@ -116,10 +116,9 @@ export function component<P extends object>(
     }
     node = new ComponentNode(C, props, ctx.app, ctx);
     ctx.children[key] = node;
-    node.initiateRender(new Fiber(node, parentFiber));
-  }
-  parentFiber.childrenMap[key] = node;
 
+    node.initiateRender(makeChildFiber(node, parentFiber));
+  }
   parentFiber.root!.reachedChildren.add(node);
   return node;
 }
@@ -327,7 +326,6 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
     bdom.mount(parent, anchor);
     this.status = STATUS.MOUNTED;
     this.fiber!.appliedToDom = true;
-    this.children = this.fiber!.childrenMap;
     this.fiber = null;
   }
 
@@ -336,6 +334,7 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
   }
 
   patch() {
+    debugger
     if (this.fiber && this.fiber.parent) {
       // we only patch here renderings coming from above. renderings initiated
       // by the component will be patched independently in the appropriate
@@ -345,8 +344,10 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
   }
   _patch() {
     const hasChildren = Object.keys(this.children).length > 0;
-    this.children = this.fiber!.childrenMap;
     this.bdom!.patch(this!.fiber!.bdom!, hasChildren);
+    if (hasChildren) {
+      this.cleanOutdatedChildren();
+    }
     this.fiber!.appliedToDom = true;
     this.fiber = null;
   }
@@ -359,6 +360,20 @@ export class ComponentNode<P extends object = any, E = any> implements VNode<Com
     this.bdom!.remove();
   }
 
+  cleanOutdatedChildren() {
+    const children = this.children;
+    for (const key in children) {
+      const node = children[key];
+      const status = node.status;
+      if (status !== STATUS.MOUNTED) {
+        delete children[key];
+        if (status !== STATUS.DESTROYED) {
+          node.destroy();
+        }
+      }
+    }
+  }
+
   // ---------------------------------------------------------------------------
   // Some debug helpers
   // ---------------------------------------------------------------------------

src/component/fibers.ts

@@ -1,6 +1,6 @@
 import { BDom, mount } from "../blockdom";
 import type { ComponentNode } from "./component_node";
-import { fibersInError, handleError } from "./error_handling";
+import { handleError } from "./error_handling";
 import { STATUS } from "./status";
 
 export function makeChildFiber(node: ComponentNode, parent: Fiber): Fiber {
@@ -9,28 +9,72 @@ export function makeChildFiber(node: ComponentNode, parent: Fiber): Fiber {
     cancelFibers(current.children);
     current.root = null;
   }
-  return new Fiber(node, parent);
+  let fiber = new Fiber(node);
+  fiber.deep = parent.deep;
+  const root = parent.root!;
+  fiber.root = root;
+  parent.children.push(fiber);
+  fiber.parent = parent;
+  root.setCounter(root.counter + 1);
+  return fiber;
 }
 
 export function makeRootFiber(node: ComponentNode): Fiber {
   let current = node.fiber;
   if (current) {
-    let root = current.root!;
+    debugger;
-    root.setCounter(root.counter + 1 - cancelFibers(current.children));
+    let parent = current.parent;
-    current.children = [];
+    let n = cancelFibers(current.children);
-    current.childrenMap = {};
+    current.root = null;
-    current.bdom = null;
+    // current.bdom = null;
-    if (current === root) {
+    if (parent) {
-      root.reachedChildren = new WeakSet();
+      let fiber = new Fiber(node);
+      fiber.deep = parent.deep;
+      const root = parent.root!;
+      fiber.root = root;
+      let index = parent.children.indexOf(current);
+      parent.children[index] = fiber;
+      // parent.children.push(fiber);
+      fiber.parent = parent;
+      // node.fiber = 
+      root.setCounter(root.counter + 1 - n);
+      if (node.willPatch.length) {
+        let index = root.willPatch.indexOf(current);
+        if (index >= 0) {
+          root.willPatch[index] = fiber;
         }
-    if (fibersInError.has(current)) {
-      fibersInError.delete(current);
-      fibersInError.delete(root);
-      current.appliedToDom = false;
       }
-    return current;
+      if (node.patched.length) {
+        let index = root.patched.indexOf(current);
+        if (index >= 0) {
+          root.patched[index] = fiber;
         }
-  const fiber = new RootFiber(node, null);
+      }
+    
+      return fiber;
+    }
+    // let parent = current.parent;
+    // let fiber = new Fiber(node);
+    // return fiber;
+
+    // cancelFibers(current.children);
+    // current.root = null;
+    // let root = current.root!;
+    // root.setCounter(root.counter + 1 - cancelFibers(current.children));
+    // current.children = [];
+    // current.bdom = null;
+    // if (current === root) {
+    //   root.reachedChildren = new WeakSet();
+    // }
+    // if (fibersInError.has(current)) {
+    //   fibersInError.delete(current);
+    //   fibersInError.delete(root);
+    //   current.appliedToDom = false;
+    // }
+    // return current;
+  }
+  const fiber = new RootFiber(node);
+  fiber.root = fiber;
   if (node.willPatch.length) {
     fiber.willPatch.push(fiber);
   }
@@ -46,11 +90,7 @@ export function makeRootFiber(node: ComponentNode): Fiber {
 function cancelFibers(fibers: Fiber[]): number {
   let result = 0;
   for (let fiber of fibers) {
-    let node = fiber.node;
+    fiber.node.fiber = null;
-    if (node.status === STATUS.NEW) {
-      node.destroy();
-    }
-    node.fiber = null;
     if (fiber.bdom) {
       // if fiber has been rendered, this means that the component props have
       // been updated. however, this fiber will not be patched to the dom, so
@@ -58,7 +98,7 @@ function cancelFibers(fibers: Fiber[]): number {
       // the same props, and skip the render completely. With the next line,
       // we kindly request the component code to force a render, so it works as
       // expected.
-      node.forceNextRender = true;
+      fiber.node.forceNextRender = true;
     } else {
       result++;
     }
@@ -67,28 +107,20 @@ function cancelFibers(fibers: Fiber[]): number {
   return result;
 }
 
+(window as any).fibers = [];
+
 export class Fiber {
   node: ComponentNode;
   bdom: BDom | null = null;
-  root: RootFiber | null; // A Fiber that has been replaced by another has no root
+  root: RootFiber | null = null; // A Fiber that has been replaced by another has no root
-  parent: Fiber | null;
+  parent: Fiber | null = null;
   children: Fiber[] = [];
   appliedToDom = false;
   deep: boolean = false;
-  childrenMap: ComponentNode["children"] = {};
 
-  constructor(node: ComponentNode, parent: Fiber | null) {
+  constructor(node: ComponentNode) {
     this.node = node;
-    this.parent = parent;
+    (window as any).fibers.push(this);
-    if (parent) {
-      this.deep = parent.deep;
-      const root = parent.root!;
-      root.setCounter(root.counter + 1);
-      this.root = root;
-      parent.children.push(this);
-    } else {
-      this.root = this as any;
-    }
   }
 
   render() {
@@ -198,6 +230,7 @@ export class RootFiber extends Fiber {
   }
 
   setCounter(newValue: number) {
+    debugger;
     this.counter = newValue;
     if (newValue === 0) {
       this.node.app.scheduler.flush();
@@ -216,15 +249,15 @@ export class MountFiber extends RootFiber {
   position: Position;
 
   constructor(node: ComponentNode, target: HTMLElement, options: MountOptions = {}) {
-    super(node, null);
+    super(node);
     this.target = target;
+    this.root = this;
     this.position = options.position || "last-child";
   }
   complete() {
     let current: Fiber | undefined = this;
     try {
       const node = this.node;
-      node.children = this.childrenMap;
       (node.app.constructor as any).validateTarget(this.target);
       if (node.bdom) {
         // this is a complicated situation: if we mount a fiber with an existing

tests/components/concurrency.test.ts

@@ -114,8 +114,8 @@ test("destroying/recreating a subwidget with different props (if start is not ov
   expect(n).toBe(2);
 
   expect([
-    "Child:willDestroy",
     "W:willRender",
+    "Child:willDestroy",
     "Child:setup",
     "Child:willStart",
     "W:rendered",
@@ -244,8 +244,8 @@ test("creating two async components, scenario 1", async () => {
   await nextTick();
   expect(fixture.innerHTML).toBe("");
   expect([
-    "ChildA:willDestroy",
     "Parent:willRender",
+    "ChildA:willDestroy",
     "ChildA:setup",
     "ChildA:willStart",
     "ChildB:setup",
@@ -696,8 +696,8 @@ test("rendering component again in next microtick", async () => {
     "Child:setup",
     "Child:willStart",
     "Parent:rendered",
-    "Child:willDestroy",
     "Parent:willRender",
+    "Child:willDestroy",
     "Child:setup",
     "Child:willStart",
     "Parent:rendered",
@@ -870,6 +870,7 @@ test("concurrent renderings scenario 2", async () => {
     "ComponentB:rendered",
   ]).toBeLogged();
 
+  debugger; 
   stateB.fromB = "c";
   await nextTick();
   expect(fixture.innerHTML).toBe("<div>1<p><span>1b</span></p></div>");
@@ -881,7 +882,7 @@ test("concurrent renderings scenario 2", async () => {
 
   defs[1].resolve(); // resolve rendering initiated in B
   await nextTick();
-  expect(fixture.innerHTML).toBe("<div>2<p><span>2c</span></p></div>");
+  debugger
   expect([
     "ComponentC:willRender",
     "ComponentC:rendered",
@@ -892,6 +893,7 @@ test("concurrent renderings scenario 2", async () => {
     "ComponentB:patched",
     "ComponentA:patched",
   ]).toBeLogged();
+  expect(fixture.innerHTML).toBe("<div>2<p><span>2c</span></p></div>");
 
   defs[0].resolve(); // resolve rendering initiated in A
   await nextTick();
@@ -1725,7 +1727,6 @@ test("concurrent renderings scenario 10", async () => {
   expect(fixture.innerHTML).toBe("<div><p></p></div>");
   expect([
     "ComponentA:willRender",
-    "ComponentC:willDestroy",
     "ComponentB:willUpdateProps",
     "ComponentA:rendered",
   ]).toBeLogged();
@@ -1736,6 +1737,7 @@ test("concurrent renderings scenario 10", async () => {
   expect(rendered).toBe(1);
   expect([
     "ComponentB:willRender",
+    "ComponentC:willDestroy",
     "ComponentC:setup",
     "ComponentC:willStart",
     "ComponentB:rendered",
@@ -2275,11 +2277,11 @@ test("concurrent renderings scenario 16", async () => {
     "D:setup",
     "D:willStart",
     "C:rendered",
-    "D:willDestroy",
     "B:willRender",
     "C:willUpdateProps",
     "B:rendered",
     "C:willRender",
+    "D:willDestroy",
     "D:setup",
     "D:willStart",
     "C:rendered",
@@ -2990,13 +2992,13 @@ test("t-key on dom node having a component", async () => {
 
   expect(fixture.innerHTML).toBe("<div>3</div>");
   expect([
-    "Child (2):willDestroy",
     "Child (3):setup",
     "Child (3):willStart",
     "Child (3):willRender",
     "Child (3):rendered",
     "Child (1):willUnmount",
     "Child (1):willDestroy",
+    "Child (2):willDestroy",
     "Child (3):mounted",
   ]).toBeLogged();
 });
@@ -3048,13 +3050,13 @@ test("t-key on dynamic async component (toggler is never patched)", async () =>
 
   expect(fixture.innerHTML).toBe("<div>3</div>");
   expect([
-    "Child (2):willDestroy",
     "Child (3):setup",
     "Child (3):willStart",
     "Child (3):willRender",
     "Child (3):rendered",
     "Child (1):willUnmount",
     "Child (1):willDestroy",
+    "Child (2):willDestroy",
     "Child (3):mounted",
   ]).toBeLogged();
 });
@@ -3107,13 +3109,13 @@ test("t-foreach with dynamic async component", async () => {
 
   expect(fixture.innerHTML).toBe("<div>3</div>");
   expect([
-    "Child (2):willDestroy",
     "Child (3):setup",
     "Child (3):willStart",
     "Child (3):willRender",
     "Child (3):rendered",
     "Child (1):willUnmount",
     "Child (1):willDestroy",
+    "Child (2):willDestroy",
     "Child (3):mounted",
   ]).toBeLogged();
 });