[E2E] Allow custom browser for Cypress database snapshot generation (#29271)

* Extract `parseArguments` into utils

* Allow custom browser for Cypress snapshots generation

e2e/runner/cypress-runner-generate-snapshots.js

 const cypress = require("cypress");
 
+const { parseArguments, args } = require("./cypress-runner-utils");
+
 const getConfig = baseUrl => {
   return {
     browser: "chrome",
@@ -11,7 +13,14 @@ const getConfig = baseUrl => {
 };
 
 const generateSnapshots = async (baseUrl, exitFunction) => {
-  const snapshotConfig = getConfig(baseUrl);
+  // We only ever care about a broswer out of all possible user arguments,
+  // when it comes to the snapshot generation.
+  // Anything else could result either in a failure or in a wrong database snapshot!
+  const { browser } = await parseArguments(args);
+  const customBrowser = browser ? { browser } : null;
+
+  const baseConfig = getConfig(baseUrl);
+  const snapshotConfig = Object.assign({}, baseConfig, customBrowser);
 
   try {
     const { status, message, totalFailed, failures } = await cypress.run(

e2e/runner/cypress-runner-run-tests.js

 const cypress = require("cypress");
-const arg = require("arg");
 
-const { executeYarnCommand } = require("./cypress-runner-utils");
-
-const args = arg(
-  {
-    "--folder": String, // The name of the folder to run files from
-    "--open": [Boolean], // Run Cypress in open mode or not? Doesn't accept additional arguments
-  },
-  { permissive: true }, // Passes all other flags and args to the Cypress parser
-);
+const {
+  executeYarnCommand,
+  parseArguments,
+  args,
+} = require("./cypress-runner-utils");
 
 const folder = args["--folder"];
 const isFolder = !!folder;
 
 const isOpenMode = args["--open"];
 
-const parseArguments = async () => {
-  const cliArgs = args._;
-
-  // cypress.cli.parseArguments requires `cypress run` as the first two arguments
-  if (cliArgs[0] !== "cypress") {
-    cliArgs.unshift("cypress");
-  }
-
-  if (cliArgs[1] !== "run") {
-    cliArgs.splice(1, 0, "run");
-  }
-
-  return await cypress.cli.parseRunArguments(cliArgs);
-};
-
 const getSourceFolder = folder => {
   return `./e2e/test/scenarios/${folder}/**/*.cy.spec.js`;
 };
@@ -50,7 +30,7 @@ const runCypress = async (baseUrl, exitFunction) => {
     spec: isFolder && getSourceFolder(folder),
   };
 
-  const userArgs = await parseArguments();
+  const userArgs = await parseArguments(args);
 
   const finalConfig = Object.assign({}, defaultConfig, userArgs);
 

e2e/runner/cypress-runner-utils.js

 const { exec } = require("child_process");
+const arg = require("arg");
 const chalk = require("chalk");
+const cypress = require("cypress");
 
 function printBold(message) {
   console.log(chalk.bold(message));
@@ -30,9 +32,34 @@ function executeYarnCommand({ command, message } = {}) {
   });
 }
 
+const args = arg(
+  {
+    "--folder": String, // The name of the folder to run files from
+    "--open": [Boolean], // Run Cypress in open mode or not? Doesn't accept additional arguments
+  },
+  { permissive: true }, // Passes all other flags and args to the Cypress parser
+);
+
+async function parseArguments(args) {
+  const cliArgs = args._;
+
+  // cypress.cli.parseArguments requires `cypress run` as the first two arguments
+  if (cliArgs[0] !== "cypress") {
+    cliArgs.unshift("cypress");
+  }
+
+  if (cliArgs[1] !== "run") {
+    cliArgs.splice(1, 0, "run");
+  }
+
+  return await cypress.cli.parseRunArguments(cliArgs);
+}
+
 module.exports = {
   printBold,
   printYellow,
   printCyan,
   executeYarnCommand,
+  parseArguments,
+  args,
 };