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How to use precacheChildNodes method in Playwright Internal

Best JavaScript code snippet using playwright-internal

ReactDOMComponentTree.js

Source:ReactDOMComponentTree.js

...59 * the DOM nodes we see. To avoid this, ReactMultiChild calls60 * `prepareToManageChildren` before we change `_renderedChildren`, at which61 * time the container's child nodes are always cached (until it unmounts).62 */63function precacheChildNodes(inst, node) {64  if (inst._flags & Flags.hasCachedChildNodes) {65    return;66  }67  var children = inst._renderedChildren;68  var childNode = node.firstChild;69  outer: for (var name in children) {70    if (!children.hasOwnProperty(name)) {71      continue;72    }73    var childInst = children[name];74    var childID = getRenderedNativeOrTextFromComponent(childInst)._domID;75    if (childID == null) {76      // We're currently unmounting this child in ReactMultiChild; skip it.77      continue;78    }79    // We assume the child nodes are in the same order as the child instances.80    for (; childNode !== null; childNode = childNode.nextSibling) {81      if ((childNode.nodeType === 1 &&82           childNode.getAttribute(ATTR_NAME) === String(childID)) ||83          (childNode.nodeType === 8 &&84           childNode.nodeValue === ' react-text: ' + childID + ' ') ||85          (childNode.nodeType === 8 &&86           childNode.nodeValue === ' react-empty: ' + childID + ' ')) {87        precacheNode(childInst, childNode);88        continue outer;89      }90    }91    // We reached the end of the DOM children without finding an ID match.92    invariant(false, 'Unable to find element with ID %s.', childID);93  }94  inst._flags |= Flags.hasCachedChildNodes;95}96/**97 * Given a DOM node, return the closest ReactDOMComponent or98 * ReactDOMTextComponent instance ancestor.99 */100function getClosestInstanceFromNode(node) {101  if (node[internalInstanceKey]) {102    return node[internalInstanceKey];103  }104  // Walk up the tree until we find an ancestor whose instance we have cached.105  var parents = [];106  while (!node[internalInstanceKey]) {107    parents.push(node);108    if (node.parentNode) {109      node = node.parentNode;110    } else {111      // Top of the tree. This node must not be part of a React tree (or is112      // unmounted, potentially).113      return null;114    }115  }116  var closest;117  var inst;118  for (; node && (inst = node[internalInstanceKey]); node = parents.pop()) {119    closest = inst;120    if (parents.length) {121      precacheChildNodes(inst, node);122    }123  }124  return closest;125}126/**127 * Given a DOM node, return the ReactDOMComponent or ReactDOMTextComponent128 * instance, or null if the node was not rendered by this React.129 */130function getInstanceFromNode(node) {131  var inst = getClosestInstanceFromNode(node);132  if (inst != null && inst._nativeNode === node) {133    return inst;134  } else {135    return null;136  }137}138/**139 * Given a ReactDOMComponent or ReactDOMTextComponent, return the corresponding140 * DOM node.141 */142function getNodeFromInstance(inst) {143  // Without this first invariant, passing a non-DOM-component triggers the next144  // invariant for a missing parent, which is super confusing.145  invariant(146    inst._nativeNode !== undefined,147    'getNodeFromInstance: Invalid argument.'148  );149  if (inst._nativeNode) {150    return inst._nativeNode;151  }152  // Walk up the tree until we find an ancestor whose DOM node we have cached.153  var parents = [];154  while (!inst._nativeNode) {155    parents.push(inst);156    invariant(157      inst._nativeParent,158      'React DOM tree root should always have a node reference.'159    );160    inst = inst._nativeParent;161  }162  // Now parents contains each ancestor that does *not* have a cached native163  // node, and `inst` is the deepest ancestor that does.164  for (; parents.length; inst = parents.pop()) {165    precacheChildNodes(inst, inst._nativeNode);166  }167  return inst._nativeNode;168}169var ReactDOMComponentTree = {170  getClosestInstanceFromNode: getClosestInstanceFromNode,171  getInstanceFromNode: getInstanceFromNode,172  getNodeFromInstance: getNodeFromInstance,173  precacheChildNodes: precacheChildNodes,174  precacheNode: precacheNode,175  uncacheNode: uncacheNode,176};...

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch();4  const context = await browser.newContext();5  const page = await context.newPage();6  await page.precacheChildNodes('input[name="q"]');7  await page.type('input[name="q"]', 'Hello');8  await page.screenshot({ path: 'google.png' });9  await browser.close();10})();

Using AI Code Generation

1const { chromium } = require("playwright");2(async () => {3  const browser = await chromium.launch();4  const context = await browser.newContext();5  const page = await context.newPage();6  await page.precacheChildNodes("body");7  await page.screenshot({ path: "google.png" });8  await browser.close();9})();10const { chromium } = require("playwright");11const { precacheChildNodes } = require("@playwright/test-utils");12(async () => {13  const browser = await chromium.launch();14  const context = await browser.newContext();15  const page = await context.newPage();16  await precacheChildNodes(page, "body");17  await page.screenshot({ path: "google.png" });18  await browser.close();19})();20precacheChildNodes(page, selector, options);

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch();4  const context = await browser.newContext();5  const page = await context.newPage();6  await page.precacheChildNodes('css=div');7  await page.waitForTimeout(5000);8  await browser.close();9})();

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch({ headless: false, slowMo: 50 });4  const context = await browser.newContext();5  await context.tracing.start({ screenshots: true, snapshots: true });6  const page = await context.newPage();7  await page.precacheChildNodes('html');8  await page.tracing.stop({ path: 'trace.zip' });9  await browser.close();10})();11#### tracing.start(options)12#### tracing.stop(options)13#### tracing.path()14#### tracing.screenshots()15#### tracing.snapshots()16#### page.tracing.start(options)

Using AI Code Generation

1const { chromium } = require('playwright');2(async () => {3  const browser = await chromium.launch();4  const page = await browser.newPage();5  await page.precacheChildNodes();6  await page.screenshot({ path: `example.png` });7  await browser.close();8})();9const { chromium } = require('playwright');10(async () => {11  const browser = await chromium.launch();12  const page = await browser.newPage();13  const dom = await page.fetch();14  console.log(dom);15  await browser.close();16})();17const puppeteer = require('puppeteer');18(async () => {19  const browser = await puppeteer.launch();20  const page = await browser.newPage();21  const dom = await page.evaluateHandle(() => document);22  console.log(dom);23  await browser.close();24})();25const { chromium } = require('playwright');26(async () => {27  const browser = await chromium.launch();28  const page = await browser.newPage();29  const dom = await page.fetch();30  console.log(dom);31  await browser.close();32})();33const puppeteer = require('puppeteer');34(async () => {35  const browser = await puppeteer.launch();36  const page = await browser.newPage();37  const dom = await page.evaluateHandle(() => document);

Using AI Code Generation

1const { chromium, devices } = require('playwright');2(async () => {3  const browser = await chromium.launch();4  const context = await browser.newContext();5  const page = await context.newPage();6  const client = await page.context().newCDPSession(page);7  await client.send('DOM.enable');8  await client.send('DOM.precacheChildNodes', { nodeId: 1 });9  await browser.close();10})();

Using AI Code Generation

1const { chromium } = require('playwright');2const { precacheChildNodes } = require('playwright/lib/server/supplements/recorder/recorderSupplement');3const fs = require('fs');4(async () => {5  const browser = await chromium.launch();6  const context = await browser.newContext();7  const page = await context.newPage();8  await precacheChildNodes(page);9  const html = await page.content();10  fs.writeFileSync('test.html', html);11  await browser.close();12})();

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