From 60a031aa2b847a61412014a73f4b09341d36db7d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mi=C5=A1ko=20Hevery?= <misko@hevery.com>
Date: Sun, 12 Nov 2023 17:07:27 -0800
Subject: [PATCH] WIP

---
 .vscode/launch.json                           |   6 +-
 .../qwik/src/core/container/render.unit.tsx   |  73 ++++++++++
 .../qwik/src/core/render/dom/notify-render.ts |   2 +-
 .../qwik/src/core/render/dom/operations.ts    |   1 +
 .../qwik/src/core/render/dom/render-dom.ts    |   3 +-
 packages/qwik/src/core/render/dom/signals.ts  |  53 +++++--
 packages/qwik/src/core/render/dom/visitor.ts  | 130 +++++++++++-------
 .../qwik/src/core/render/ssr/render-ssr.ts    |  10 +-
 packages/qwik/src/core/state/common.ts        |   2 +-
 packages/qwik/src/core/util/element.ts        |   2 +-
 10 files changed, 209 insertions(+), 73 deletions(-)
 create mode 100644 packages/qwik/src/core/container/render.unit.tsx

diff --git a/.vscode/launch.json b/.vscode/launch.json
index 66594547d82..9edbc545c8f 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -33,13 +33,13 @@
     },
     {
       "type": "node",
-      "name": "vscode-jest-tests",
+      "name": "vitest",
       "request": "launch",
       "console": "integratedTerminal",
       "internalConsoleOptions": "neverOpen",
-      "program": "${workspaceFolder}/node_modules/jest/bin/jest.js",
+      "program": "${workspaceFolder}/./node_modules/vitest/vitest.mjs",
       "cwd": "${workspaceFolder}",
-      "args": ["--runInBand", "--watchAll=false"]
+      "args": ["--threads=false", "packages/qwik/src/core/container/render.unit.tsx"]
     }
   ]
 }
diff --git a/packages/qwik/src/core/container/render.unit.tsx b/packages/qwik/src/core/container/render.unit.tsx
new file mode 100644
index 00000000000..85267be744d
--- /dev/null
+++ b/packages/qwik/src/core/container/render.unit.tsx
@@ -0,0 +1,73 @@
+import { assert, suite, test } from 'vitest';
+import type { JSXNode } from '../../jsx-runtime';
+import { renderToString } from '../../server/render';
+import { createDocument } from '../../testing/document';
+import { createDOM } from '../../testing/library';
+import { component$ } from '../component/component.public';
+import { _fnSignal } from '../internal';
+import { useSignal } from '../use/use-signal';
+
+suite('jsx signals', () => {
+  const RenderJSX = component$(() => {
+    const jsx = useSignal<string | JSXNode>(<span>SSR</span>);
+    return (
+      <>
+        <button class="text" onClick$={() => (jsx.value = 'text')} />
+        <button class="i" onClick$={() => (jsx.value = <i>i</i>)} />
+        <button class="b" onClick$={() => (jsx.value = <b>b</b>)} />
+        <button class="virtual" onClick$={() => (jsx.value = <>v</>)} />
+        <div class="jsx">{jsx.value}</div>
+        <div class="jsx-signal">{_fnSignal((p0) => p0.value, [jsx], 'p0.value')}</div>
+      </>
+    );
+  });
+
+  test.skip('SSR jsx', async () => {
+    const output = await renderToString(<RenderJSX />, { containerTagName: 'div' });
+    const document = createDocument();
+    document.body.innerHTML = output.html;
+    const div = document.querySelector('.jsx')!;
+    assert.equal(div.innerHTML, '<span>SSR</span>');
+    const divSignal = document.querySelector('.jsx-signal')!;
+    assert.equal(divSignal.innerHTML, '<!--t=1--><span>SSR</span><!---->');
+  });
+
+  test('CSR jsx', async () => {
+    const { screen, render, userEvent } = await createDOM();
+
+    await render(<RenderJSX />);
+    const div = screen.querySelector('.jsx')!;
+    const divSignal = screen.querySelector('.jsx-signal')!;
+    assert.equal(div.innerHTML, '<span>SSR</span>');
+    assert.equal(divSignal.innerHTML, '<span>SSR</span>');
+
+    await userEvent('button.text', 'click');
+    assert.equal(div.innerHTML, 'text');
+    assert.equal(divSignal.innerHTML, 'text');
+
+    await userEvent('button.i', 'click');
+    assert.equal(div.innerHTML, '<i>i</i>');
+    assert.equal(divSignal.innerHTML, '<i>i</i>');
+
+    await userEvent('button.b', 'click');
+    assert.equal(div.innerHTML, '<b>b</b>');
+    assert.equal(divSignal.innerHTML, '<b>b</b>');
+
+    await userEvent('button.virtual', 'click');
+    assert.equal(div.innerHTML, 'v');
+    assert.equal(divSignal.innerHTML, 'v');
+
+    await userEvent('button.b', 'click');
+    assert.equal(div.innerHTML, '<b>b</b>');
+    assert.equal(divSignal.innerHTML, '<b>b</b>');
+
+    await userEvent('button.text', 'click');
+    assert.equal(div.innerHTML, 'text');
+    assert.equal(divSignal.innerHTML, 'text');
+  });
+
+  //TODO(misko): More tests
+  // - Render component
+  // - Render promise
+  // - Render array of JSX
+});
diff --git a/packages/qwik/src/core/render/dom/notify-render.ts b/packages/qwik/src/core/render/dom/notify-render.ts
index 577caf0acd1..e2d7402c4bc 100644
--- a/packages/qwik/src/core/render/dom/notify-render.ts
+++ b/packages/qwik/src/core/render/dom/notify-render.ts
@@ -176,7 +176,7 @@ const renderMarked = async (containerState: ContainerState): Promise<void> => {
     }
 
     signalOperations.forEach((op) => {
-      executeSignalOperation(staticCtx, op);
+      executeSignalOperation(rCtx, op);
     });
 
     // Add post operations
diff --git a/packages/qwik/src/core/render/dom/operations.ts b/packages/qwik/src/core/render/dom/operations.ts
index c3cce01e2df..3de37de6397 100644
--- a/packages/qwik/src/core/render/dom/operations.ts
+++ b/packages/qwik/src/core/render/dom/operations.ts
@@ -205,6 +205,7 @@ export const createTemplate = (doc: Document, slotName: string) => {
 
 export const executeDOMRender = (staticCtx: RenderStaticContext) => {
   for (const op of staticCtx.$operations$) {
+    // PERF(misko): polymorphic execution
     op.$operation$.apply(undefined, op.$args$);
   }
   resolveSlotProjection(staticCtx);
diff --git a/packages/qwik/src/core/render/dom/render-dom.ts b/packages/qwik/src/core/render/dom/render-dom.ts
index 79f281bb2ec..53b3611ed91 100644
--- a/packages/qwik/src/core/render/dom/render-dom.ts
+++ b/packages/qwik/src/core/render/dom/render-dom.ts
@@ -165,10 +165,11 @@ export const processData = (
   } else if (isJSXNode(node)) {
     return processNode(node, invocationContext);
   } else if (isSignal(node)) {
-    const newNode = new ProcessedJSXNodeImpl('#text', EMPTY_OBJ, null, EMPTY_ARRAY, 0, null);
+    const newNode = new ProcessedJSXNodeImpl('#signal', EMPTY_OBJ, null, EMPTY_ARRAY, 0, null);
     newNode.$signal$ = node;
     return newNode;
   } else if (isArray(node)) {
+    // PERF(misko): possible place to make it faster by not creating promises unnecessarily
     const output = promiseAll(node.flatMap((n) => processData(n, invocationContext)));
     return maybeThen(output, (array) => array.flat(100).filter(isNotNullable));
   } else if (isPromise(node)) {
diff --git a/packages/qwik/src/core/render/dom/signals.ts b/packages/qwik/src/core/render/dom/signals.ts
index 390977f5740..1dfaa7c2cfa 100644
--- a/packages/qwik/src/core/render/dom/signals.ts
+++ b/packages/qwik/src/core/render/dom/signals.ts
@@ -1,18 +1,20 @@
+import { assertEqual } from '../../error/assert';
+import { qError } from '../../error/error';
 import type { SubscriberSignal } from '../../state/common';
-import { tryGetContext } from '../../state/context';
+import { getContext, tryGetContext } from '../../state/context';
 import { trackSignal } from '../../use/use-core';
-import { jsxToString, serializeClassWithHost, stringifyStyle } from '../execute-component';
-import type { RenderStaticContext } from '../types';
-import { setProperty } from './operations';
-import { getVdom } from './render-dom';
-import { smartSetProperty, SVG_NS } from './visitor';
+import { logError } from '../../util/log';
+import { serializeClassWithHost, stringifyStyle } from '../execute-component';
+import type { RenderContext } from '../types';
+import { insertBefore, removeNode } from './operations';
+import { getVdom, processData, type ProcessedJSXNode } from './render-dom';
+import type { QwikElement } from './virtual-element';
+import { SVG_NS, createElm, diffVnode, getVnodeFromEl, smartSetProperty } from './visitor';
 
-export const executeSignalOperation = (
-  staticCtx: RenderStaticContext,
-  operation: SubscriberSignal
-) => {
+export const executeSignalOperation = (rCtx: RenderContext, operation: SubscriberSignal) => {
   try {
     const type = operation[0];
+    const staticCtx = rCtx.$static$;
     switch (type) {
       case 1:
       case 2: {
@@ -49,13 +51,36 @@ export const executeSignalOperation = (
       }
       case 3:
       case 4: {
-        const elm: Text = operation[3] as Text;
-
+        const elm = operation[3];
         if (!staticCtx.$visited$.includes(elm)) {
           // assertTrue(elm.isConnected, 'text node must be connected to the dom');
           staticCtx.$containerState$.$subsManager$.$clearSignal$(operation);
-          const value = trackSignal(operation[2], operation.slice(0, -1) as any);
-          return setProperty(staticCtx, elm, 'data', jsxToString(value));
+          const signal = operation[2];
+          // MISKO: I believe no `invocationContext` is OK because the JSX in signal
+          // has already been converted to JSX and there is nothing to execute there.
+          const invocationContext = undefined;
+          const newVnode = processData(signal.value, invocationContext) as ProcessedJSXNode;
+          const oldVnode = getVnodeFromEl(elm);
+          rCtx.$cmpCtx$ = getContext(operation[1] as QwikElement, rCtx.$static$.$containerState$);
+          if (
+            oldVnode.$type$ == newVnode.$type$ &&
+            oldVnode.$key$ == newVnode.$key$ &&
+            oldVnode.$id$ == newVnode.$id$
+          ) {
+            diffVnode(rCtx, oldVnode, newVnode, 0);
+          } else {
+            const promises: Promise<any>[] = []; // TODO(misko): hook this up
+            const oldNode = oldVnode.$elm$;
+            const newElm = createElm(rCtx, newVnode, 0, promises);
+            if (promises.length) {
+              logError('Rendering promises in JSX signals is not supported');
+            }
+            rCtx.$static$;
+            operation[3] = newElm;
+            insertBefore(rCtx.$static$, elm.parentElement!, newElm, oldNode);
+            oldNode && removeNode(staticCtx, oldNode);
+          }
+          trackSignal(operation[2], operation.slice(0, -1) as any);
         }
       }
     }
diff --git a/packages/qwik/src/core/render/dom/visitor.ts b/packages/qwik/src/core/render/dom/visitor.ts
index 6344bacb0bd..2d2185ef51a 100644
--- a/packages/qwik/src/core/render/dom/visitor.ts
+++ b/packages/qwik/src/core/render/dom/visitor.ts
@@ -1,7 +1,5 @@
-import { ELEMENT_ID, OnRenderProp, QSlot, QSlotRef, QSlotS, QStyle } from '../../util/markers';
-import { isOnProp, PREVENT_DEFAULT, setEvent } from '../../state/listeners';
-import type { ValueOrPromise } from '../../util/types';
-import { isPromise, promiseAll, promiseAllLazy, maybeThen } from '../../util/promises';
+import type { OnRenderFn } from '../../component/component.public';
+import { getEventName, setRef, type ContainerState } from '../../container/container';
 import {
   assertDefined,
   assertElement,
@@ -10,20 +8,14 @@ import {
   assertQwikElement,
   assertTrue,
 } from '../../error/assert';
-import { logWarn } from '../../util/log';
-import { qDev, qInspector, qTest } from '../../util/qdev';
-import type { OnRenderFn } from '../../component/component.public';
-import { directGetAttribute, directSetAttribute } from '../fast-calls';
-import { SKIP_RENDER_TYPE } from '../jsx/jsx-runtime';
 import { assertQrl, isQrl } from '../../qrl/qrl-class';
+import { PREVENT_DEFAULT, isOnProp, setEvent } from '../../state/listeners';
 import { isElement, isQwikElement, isText, isVirtualElement } from '../../util/element';
-import {
-  getVdom,
-  type ProcessedJSXNode,
-  ProcessedJSXNodeImpl,
-  renderComponent,
-} from './render-dom';
-import type { RenderContext, RenderStaticContext } from '../types';
+import { logWarn } from '../../util/log';
+import { ELEMENT_ID, OnRenderProp, QSlot, QSlotRef, QSlotS, QStyle } from '../../util/markers';
+import { isPromise, maybeThen, promiseAll, promiseAllLazy } from '../../util/promises';
+import { qDev, qInspector, qTest } from '../../util/qdev';
+import type { ValueOrPromise } from '../../util/types';
 import {
   dangerouslySetInnerHTML,
   isAriaAttribute,
@@ -35,17 +27,47 @@ import {
   static_subtree,
   stringifyStyle,
 } from '../execute-component';
-import { type ContainerState, setRef, getEventName } from '../../container/container';
+import { directGetAttribute, directSetAttribute } from '../fast-calls';
+import { SKIP_RENDER_TYPE, isJSXNode } from '../jsx/jsx-runtime';
+import type { RenderContext, RenderStaticContext } from '../types';
+import {
+  ProcessedJSXNodeImpl,
+  getVdom,
+  processData,
+  renderComponent,
+  type ProcessedJSXNode,
+} from './render-dom';
 import {
+  VIRTUAL,
   getRootNode,
   newVirtualElement,
   processVirtualNodes,
   queryAllVirtualByAttribute,
   type QwikElement,
-  VIRTUAL,
   type VirtualElement,
 } from './virtual-element';
 
+import { isBrowser } from '@builder.io/qwik/build';
+import {
+  getProxyTarget,
+  getSubscriptionManager,
+  type SubscriberC,
+  type SubscriptionManager,
+} from '../../state/common';
+import { _IMMUTABLE, _IMMUTABLE_PREFIX } from '../../state/constants';
+import {
+  HOST_FLAG_DIRTY,
+  HOST_FLAG_NEED_ATTACH_LISTENER,
+  cleanupContext,
+  createContext,
+  getContext,
+  tryGetContext,
+  type QContext,
+} from '../../state/context';
+import { isSignal } from '../../state/signal';
+import { ReadWriteProxyHandler, createPropsState, createProxy } from '../../state/store';
+import { trackSignal } from '../../use/use-core';
+import { EMPTY_OBJ } from '../../util/flyweight';
 import {
   appendChild,
   createElement,
@@ -61,26 +83,6 @@ import {
   setProperty,
   setPropertyPost,
 } from './operations';
-import { EMPTY_OBJ } from '../../util/flyweight';
-import { isSignal } from '../../state/signal';
-import {
-  cleanupContext,
-  createContext,
-  getContext,
-  HOST_FLAG_DIRTY,
-  HOST_FLAG_NEED_ATTACH_LISTENER,
-  type QContext,
-  tryGetContext,
-} from '../../state/context';
-import {
-  getSubscriptionManager,
-  getProxyTarget,
-  type SubscriptionManager,
-} from '../../state/common';
-import { createPropsState, createProxy, ReadWriteProxyHandler } from '../../state/store';
-import { _IMMUTABLE, _IMMUTABLE_PREFIX } from '../../state/constants';
-import { trackSignal } from '../../use/use-core';
-import { isBrowser } from '@builder.io/qwik/build';
 
 export const SVG_NS = 'http://www.w3.org/2000/svg';
 
@@ -637,7 +639,7 @@ const getSlotName = (node: ProcessedJSXNode): string => {
   return node.$props$[QSlot] ?? '';
 };
 
-const createElm = (
+export const createElm = (
   rCtx: RenderContext,
   vnode: ProcessedJSXNode,
   flags: number,
@@ -647,18 +649,48 @@ const createElm = (
   const doc = rCtx.$static$.$doc$;
   const currentComponent = rCtx.$cmpCtx$;
   if (tag === '#text') {
-    const signal = vnode.$signal$;
-    const elm = doc.createTextNode(vnode.$text$);
-    if (signal) {
-      assertDefined(currentComponent, 'signals can not be used outside components');
-      const subs =
-        flags & IS_IMMUTABLE
-          ? ([3, elm, signal, elm] as const)
-          : ([4, currentComponent.$element$, signal, elm] as const);
+    return (vnode.$elm$ = doc.createTextNode(vnode.$text$));
+  }
 
-      elm.data = vnode.$text$ = jsxToString(trackSignal(signal, subs));
+  if (tag === '#signal') {
+    const signal = vnode.$signal$!;
+    assertDefined(signal, 'expecting signal here');
+    assertDefined(currentComponent, 'signals can not be used outside components');
+    const signalValue = signal.value;
+    if (isJSXNode(signalValue)) {
+      // convert signal value to ProcessedJSXNode
+      const processedSignal = processData(signalValue);
+      if (isSignal(processedSignal)) {
+        throw new Error('NOT IMPLEMENTED: Promise');
+      } else if (Array.isArray(processedSignal)) {
+        throw new Error('NOT IMPLEMENTED: Array');
+      } else {
+        // crate elements
+        const elm = createElm(rCtx, processedSignal as ProcessedJSXNode, flags, promises);
+        // create subscription
+        trackSignal(
+          signal,
+          flags & IS_IMMUTABLE
+            ? ([3, elm, signal, elm] as SubscriberC)
+            : ([4, currentComponent.$element$, signal, elm] as SubscriberC)
+        );
+        // update the vNode for future diff.
+        return (vnode.$elm$ = elm);
+      }
+    } else {
+      // create element
+      const elm = doc.createTextNode(vnode.$text$);
+      elm.data = vnode.$text$ = jsxToString(signalValue);
+      // create subscription
+      trackSignal(
+        signal,
+        flags & IS_IMMUTABLE
+          ? ([3, elm, signal, elm] as SubscriberC)
+          : ([4, currentComponent.$element$, signal, elm] as SubscriberC)
+      );
+      // update the vNode for future diff.
+      return (vnode.$elm$ = elm);
     }
-    return (vnode.$elm$ = elm);
   }
 
   let elm: QwikElement;
diff --git a/packages/qwik/src/core/render/ssr/render-ssr.ts b/packages/qwik/src/core/render/ssr/render-ssr.ts
index b8dd75798f3..a11c8a43c07 100644
--- a/packages/qwik/src/core/render/ssr/render-ssr.ts
+++ b/packages/qwik/src/core/render/ssr/render-ssr.ts
@@ -875,9 +875,13 @@ const processData = (
             : ([4, hostEl, node, ('#' + id) as any] as const);
 
         value = trackSignal(node, subs);
-        const str = jsxToString(value);
-        ssrCtx.$static$.$textNodes$.set(str, id);
-        stream.write(`<!--t=${id}-->${escapeHtml(str)}<!---->`);
+        if (isString(value)) {
+          const str = jsxToString(value);
+          ssrCtx.$static$.$textNodes$.set(str, id);
+        }
+        stream.write(`<!--t=${id}-->`);
+        processData(value, rCtx, ssrCtx, stream, flags, beforeClose);
+        stream.write(`<!---->`);
         return;
       } else {
         value = invoke(ssrCtx.$invocationContext$, () => node.value);
diff --git a/packages/qwik/src/core/state/common.ts b/packages/qwik/src/core/state/common.ts
index b4f6b09e6c3..3a7002f66ee 100644
--- a/packages/qwik/src/core/state/common.ts
+++ b/packages/qwik/src/core/state/common.ts
@@ -199,7 +199,7 @@ type SubscriberB = readonly [
   prop: string,
 ];
 
-type SubscriberC = readonly [
+export type SubscriberC = readonly [
   type: 3 | 4,
   host: SubscriberHost | Text,
   signal: Signal,
diff --git a/packages/qwik/src/core/util/element.ts b/packages/qwik/src/core/util/element.ts
index f02bd4b52fd..f0809421804 100644
--- a/packages/qwik/src/core/util/element.ts
+++ b/packages/qwik/src/core/util/element.ts
@@ -26,7 +26,7 @@ export const isVirtualElement = (value: Node | VirtualElement): value is Virtual
   return value.nodeType === 111;
 };
 
-export const isText = (value: Node): value is Text => {
+export const isText = (value: Node | QwikElement): value is Text => {
   return value.nodeType === 3;
 };