Dependency Upgrade

// compatibility-matrix.jsconst compatibilityMatrix = {  react: {    "16.x": {      "react-dom": "^16.0.0",      "react-router-dom": "^5.0.0",      "@testing-library/react": "^11.0.0",    },    "17.x": {      "react-dom": "^17.0.0",      "react-router-dom": "^5.0.0 || ^6.0.0",      "@testing-library/react": "^12.0.0",    },    "18.x": {      "react-dom": "^18.0.0",      "react-router-dom": "^6.0.0",      "@testing-library/react": "^13.0.0",    },  },};
function checkCompatibility(packages) {  // Validate package versions against matrix}

// tests/compatibility.test.jsdescribe("Dependency Compatibility", () => {  it("should have compatible React versions", () => {    const reactVersion = require("react/package.json").version;    const reactDomVersion = require("react-dom/package.json").version;
    expect(reactVersion).toBe(reactDomVersion);  });
  it("should not have peer dependency warnings", () => {    // Run npm ls and check for warnings  });});

// migration-script.jsconst fs = require("fs");const glob = require("glob");
glob("src/**/*.tsx", (err, files) => {  files.forEach((file) => {    let content = fs.readFileSync(file, "utf8");
    // Replace old API with new API    content = content.replace(      /componentWillMount/g,      "UNSAFE_componentWillMount",    );
    // Update imports    content = content.replace(      /import { Component } from 'react'/g,      "import React, { Component } from 'react'",    );
    fs.writeFileSync(file, content);  });});

// Ensure tests pass before and after upgradenpm run test
// Update test utilities if needednpm install @testing-library/react@latest

// tests/integration/app.test.jsdescribe("App Integration", () => {  it("should render without crashing", () => {    render(<App />);  });
  it("should handle navigation", () => {    const { getByText } = render(<App />);    fireEvent.click(getByText("Navigate"));    expect(screen.getByText("New Page")).toBeInTheDocument();  });});

// visual-regression.test.jsdescribe("Visual Regression", () => {  it("should match snapshot", () => {    const { container } = render(<App />);    expect(container.firstChild).toMatchSnapshot();  });});

// cypress/e2e/app.cy.jsdescribe("E2E Tests", () => {  it("should complete user flow", () => {    cy.visit("/");    cy.get('[data-testid="login"]').click();    cy.get('input[name="email"]').type("[email protected]");    cy.get('button[type="submit"]').click();    cy.url().should("include", "/dashboard");  });});

// rollback.sh#!/bin/bash
# Save current stategit stashgit checkout -b upgrade-branch
# Attempt upgradenpm install package@latest
# Run testsif npm run test; then  echo "Upgrade successful"  git add package.json package-lock.json  git commit -m "chore: upgrade package"else  echo "Upgrade failed, rolling back"  git checkout main  git branch -D upgrade-branch  npm install  # Restore from package-lock.jsonfi