chore: tests for launcher/launch, refactor process spawning for readability

Author: cacieprins

packages/launcher/index.ts

@@ -1,6 +1,6 @@
 import { detect, detectByPath } from './lib/detect'
 
-import { launch } from './lib/browsers'
+import { launch } from './lib/launch'
 
 export {
   detect,

packages/launcher/lib/browsers.ts

@@ -3,7 +3,7 @@ import _, { compact, extend, find } from 'lodash'
 import os from 'os'
 import { removeDuplicateBrowsers } from '@packages/data-context/src/sources/BrowserDataSource'
 import { knownBrowsers } from './known-browsers'
-import * as darwinHelper from './darwin'
+import * as darwinHelper from './darwinHelpers'
 import { notDetectedAtPathErr } from './errors'
 import * as linuxHelper from './linux'
 import Debug from 'debug'

packages/launcher/lib/darwin/index.ts renamed to packages/launcher/lib/darwinHelpers/index.ts

@@ -0,0 +1,28 @@
+import Debug from 'debug'
+import type * as cp from 'child_process'
+import type { FoundBrowser } from '@packages/types'
+import type { Readable } from 'stream'
+import { PlatformFactory } from './platforms/PlatformFactory'
+
+export const debug = Debug('cypress:launcher:browsers')
+
+/** starts a found browser and opens URL if given one */
+export type LaunchedBrowser = cp.ChildProcessByStdio<null, Readable, Readable>
+
+// NOTE: For Firefox, geckodriver is used to launch the browser
+export function launch (
+  browser: FoundBrowser,
+  url: string,
+  args: string[] = [],
+  browserEnv = {},
+) {
+  debug('launching browser %o', { browser, url })
+
+  // We shouldn't need to check this, because FoundBrowser.path is
+  // not optional.
+  if (!browser.path) {
+    throw new Error(`Browser ${browser.name} is missing path`)
+  }
+
+  return PlatformFactory.select().launch(browser, url, args, browserEnv)
+}

packages/launcher/lib/darwin/util.ts renamed to packages/launcher/lib/darwinHelpers/util.ts

@@ -0,0 +1,29 @@
+// this file is named XDarwin because intellisense gets confused with '../darwin/'
+import { ChildProcess, spawn } from 'child_process'
+import { Platform } from './Platform'
+import type { FoundBrowser } from '@packages/types'
+import os from 'os'
+
+export class Darwin extends Platform {
+  launch (browser: FoundBrowser, url: string, args: string[], env: Record<string, string> = {}): ChildProcess {
+    if (os.arch() === 'arm64') {
+      const proc = spawn(
+        'arch',
+        [browser.path, url, ...args], {
+          ...Platform.defaultSpawnOpts,
+          env: {
+            ARCHPREFERENCE: 'arm64,x86_64',
+            ...Platform.defaultSpawnOpts.env,
+            ...env,
+          },
+        },
+      )
+
+      this.addDebugListeners(proc, browser)
+
+      return proc
+    }
+
+    return super.launch(browser, url, args, env)
+  }
+}

packages/launcher/lib/detect.ts

@@ -0,0 +1,4 @@
+import { Platform } from './Platform'
+
+export class Linux extends Platform {
+}

packages/launcher/lib/launch.ts

@@ -0,0 +1,46 @@
+import type { FoundBrowser } from '@packages/types'
+import { ChildProcess, spawn, SpawnOptions } from 'child_process'
+import Debug from 'debug'
+
+export const debug = Debug('cypress:launcher:browsers')
+
+export abstract class Platform {
+  launch (browser: FoundBrowser, url: string, args: string[], env: Record<string, string> = {}): ChildProcess {
+    debug('launching browser %o', { browser, url, args, env })
+
+    const proc = spawn(browser.path, [url, ...args], {
+      ...Platform.defaultSpawnOpts,
+      env: {
+        ...Platform.defaultSpawnOpts.env,
+        ...env,
+      },
+    })
+
+    this.addDebugListeners(proc, browser)
+
+    return proc
+  }
+
+  protected addDebugListeners (proc: ChildProcess, browser: FoundBrowser) {
+    proc.stdout?.on('data', (buf) => {
+      debug('%s stdout: %s', browser.name, String(buf).trim())
+    })
+
+    proc.stderr?.on('data', (buf) => {
+      debug('%s stderr: %s', browser.name, String(buf).trim())
+    })
+
+    proc.on('exit', (code, signal) => {
+      debug('%s exited: %o', browser.name, { code, signal })
+    })
+  }
+
+  static get defaultSpawnOpts (): SpawnOptions {
+    return {
+      stdio: ['ignore', 'pipe', 'pipe'],
+      env: {
+        ...process.env,
+      },
+    }
+  }
+}

packages/launcher/lib/platforms/Darwin.ts

@@ -0,0 +1,20 @@
+import os from 'os'
+import type { Platform } from './Platform'
+import { Darwin } from './XDarwin'
+import { Linux } from './Linux'
+import { Windows } from './Windows'
+
+export class PlatformFactory {
+  static select (): Platform {
+    switch (os.platform()) {
+      case 'darwin':
+        return new Darwin()
+      case 'linux':
+        return new Linux()
+      case 'win32':
+        return new Windows()
+      default:
+        throw new Error(`Unsupported platform: ${os.platform()} ${os.arch()}`)
+    }
+  }
+}