♻️ Refactor download to work with new addons

This also makes things significantly easier to read

src/commands/download/firefox.ts

@@ -0,0 +1,101 @@
+import execa from 'execa'
+import { existsSync, mkdirSync, rmdirSync } from 'fs'
+import { resolve } from 'path'
+import { bin_name } from '../..'
+import { BASH_PATH, ENGINE_DIR, MELON_TMP_DIR } from '../../constants'
+import { log } from '../../log'
+import { commandExistsSync } from '../../utils/commandExists'
+import { downloadFileToLocation } from '../../utils/download'
+import { ensureDir, windowsPathToUnix } from '../../utils/fs'
+import { init } from '../init'
+
+export function shouldSetupFirefoxSource() {
+  return !(
+    existsSync(ENGINE_DIR) &&
+    existsSync(resolve(ENGINE_DIR, 'toolkit', 'moz.build'))
+  )
+}
+
+export async function setupFirefoxSource(version: string) {
+  const firefoxSourceTar = await downloadFirefoxSource(version)
+
+  await unpackFirefoxSource(firefoxSourceTar)
+
+  if (!process.env.CI_SKIP_INIT) {
+    log.info('Init firefox')
+    await init(ENGINE_DIR)
+  }
+}
+
+async function unpackFirefoxSource(name: string): Promise<void> {
+  log.info(`Unpacking Firefox...`)
+
+  if (existsSync(ENGINE_DIR)) rmdirSync(ENGINE_DIR)
+  mkdirSync(ENGINE_DIR)
+
+  let tarExec = 'tar'
+
+  // On MacOS, we need to use gnu tar, otherwise tar doesn't behave how we
+  // would expect it to behave, so this section is responsible for handling
+  // that
+  //
+  // If BSD tar adds --transform support in the future, we can use that
+  // instead
+  if (process.platform == 'darwin') {
+    // GNU Tar doesn't come preinstalled on any MacOS machines, so we need to
+    // check for it and ask for the user to install it if necessary
+    if (!commandExistsSync('gtar')) {
+      throw new Error(
+        `GNU Tar is required to extract Firefox's source on MacOS. Please install it using the command |brew install gnu-tar| and try again`
+      )
+    }
+
+    tarExec = 'gtar'
+  }
+
+  await execa(
+    tarExec,
+    [
+      '--strip-components=1',
+      process.platform == 'win32' ? '--force-local' : null,
+      '-xf',
+      windowsPathToUnix(resolve(MELON_TMP_DIR, name)),
+      '-C',
+      windowsPathToUnix(ENGINE_DIR),
+    ].filter((x) => x) as string[],
+    {
+      // HACK: Use bash shell on windows to get a sane version of tar that works
+      shell: BASH_PATH || false,
+    }
+  )
+}
+
+async function downloadFirefoxSource(version: string) {
+  const base = `https://archive.mozilla.org/pub/firefox/releases/${version}/source/`
+  const filename = `firefox-${version}.source.tar.xz`
+
+  const url = base + filename
+
+  const fsParent = MELON_TMP_DIR
+  const fsSaveLocation = resolve(fsParent, filename)
+
+  log.info(`Locating Firefox release ${version}...`)
+
+  await ensureDir(fsParent)
+
+  if (existsSync(fsSaveLocation)) {
+    log.info('Using cached download')
+    return filename
+  }
+
+  // Do not re-download if there is already an existing workspace present
+  if (existsSync(ENGINE_DIR))
+    log.error(
+      `Workspace already exists.\nRemove that workspace and run |${bin_name} download ${version}| again.`
+    )
+
+  log.info(`Downloading Firefox release ${version}...`)
+
+  await downloadFileToLocation(url, resolve(MELON_TMP_DIR, filename))
+  return filename
+}