File Explorer

1// The goal here is to minimize both git workload and2// the number of refs we download over the network.3//4// Every method ends up with the checked out working dir5// at the specified ref, and resolves with the git sha.6 7// Only certain whitelisted hosts get shallow cloning.8// Many hosts (including GHE) don't always support it.9// A failed shallow fetch takes a LOT longer than a full10// fetch in most cases, so we skip it entirely.11// Set opts.gitShallow = true/false to force this behavior12// one way or the other.13const shallowHosts = new Set([14  'github.com',15  'gist.github.com',16  'gitlab.com',17  'bitbucket.com',18  'bitbucket.org',19])20// we have to use url.parse until we add the same shim that hosted-git-info has21// to handle scp:// urls22const { parse } = require('url') // eslint-disable-line node/no-deprecated-api23const path = require('path')24 25const getRevs = require('./revs.js')26const spawn = require('./spawn.js')27const { isWindows } = require('./utils.js')28 29const pickManifest = require('npm-pick-manifest')30const fs = require('fs/promises')31 32module.exports = (repo, ref = 'HEAD', target = null, opts = {}) =>33  getRevs(repo, opts).then(revs => clone(34    repo,35    revs,36    ref,37    resolveRef(revs, ref, opts),38    target || defaultTarget(repo, opts.cwd),39    opts40  ))41 42const maybeShallow = (repo, opts) => {43  if (opts.gitShallow === false || opts.gitShallow) {44    return opts.gitShallow45  }46  return shallowHosts.has(parse(repo).host)47}48 49const defaultTarget = (repo, /* istanbul ignore next */ cwd = process.cwd()) =>50  path.resolve(cwd, path.basename(repo.replace(/[/\\]?\.git$/, '')))51 52const clone = (repo, revs, ref, revDoc, target, opts) => {53  if (!revDoc) {54    return unresolved(repo, ref, target, opts)55  }56  if (revDoc.sha === revs.refs.HEAD.sha) {57    return plain(repo, revDoc, target, opts)58  }59  if (revDoc.type === 'tag' || revDoc.type === 'branch') {60    return branch(repo, revDoc, target, opts)61  }62  return other(repo, revDoc, target, opts)63}64 65const resolveRef = (revs, ref, opts) => {66  const { spec = {} } = opts67  ref = spec.gitCommittish || ref68  /* istanbul ignore next - will fail anyway, can't pull */69  if (!revs) {70    return null71  }72  if (spec.gitRange) {73    return pickManifest(revs, spec.gitRange, opts)74  }75  if (!ref) {76    return revs.refs.HEAD77  }78  if (revs.refs[ref]) {79    return revs.refs[ref]80  }81  if (revs.shas[ref]) {82    return revs.refs[revs.shas[ref][0]]83  }84  return null85}86 87// pull request or some other kind of advertised ref88const other = (repo, revDoc, target, opts) => {89  const shallow = maybeShallow(repo, opts)90 91  const fetchOrigin = ['fetch', 'origin', revDoc.rawRef]92    .concat(shallow ? ['--depth=1'] : [])93 94  const git = (args) => spawn(args, { ...opts, cwd: target })95  return fs.mkdir(target, { recursive: true })96    .then(() => git(['init']))97    .then(() => isWindows(opts)98      ? git(['config', '--local', '--add', 'core.longpaths', 'true'])99      : null)100    .then(() => git(['remote', 'add', 'origin', repo]))101    .then(() => git(fetchOrigin))102    .then(() => git(['checkout', revDoc.sha]))103    .then(() => updateSubmodules(target, opts))104    .then(() => revDoc.sha)105}106 107// tag or branches.  use -b108const branch = (repo, revDoc, target, opts) => {109  const args = [110    'clone',111    '-b',112    revDoc.ref,113    repo,114    target,115    '--recurse-submodules',116  ]117  if (maybeShallow(repo, opts)) {118    args.push('--depth=1')119  }120  if (isWindows(opts)) {121    args.push('--config', 'core.longpaths=true')122  }123  return spawn(args, opts).then(() => revDoc.sha)124}125 126// just the head.  clone it127const plain = (repo, revDoc, target, opts) => {128  const args = [129    'clone',130    repo,131    target,132    '--recurse-submodules',133  ]134  if (maybeShallow(repo, opts)) {135    args.push('--depth=1')136  }137  if (isWindows(opts)) {138    args.push('--config', 'core.longpaths=true')139  }140  return spawn(args, opts).then(() => revDoc.sha)141}142 143const updateSubmodules = async (target, opts) => {144  const hasSubmodules = await fs.stat(`${target}/.gitmodules`)145    .then(() => true)146    .catch(() => false)147  if (!hasSubmodules) {148    return null149  }150  return spawn([151    'submodule',152    'update',153    '-q',154    '--init',155    '--recursive',156  ], { ...opts, cwd: target })157}158 159const unresolved = (repo, ref, target, opts) => {160  // can't do this one shallowly, because the ref isn't advertised161  // but we can avoid checking out the working dir twice, at least162  const lp = isWindows(opts) ? ['--config', 'core.longpaths=true'] : []163  const cloneArgs = ['clone', '--mirror', '-q', repo, target + '/.git']164  const git = (args) => spawn(args, { ...opts, cwd: target })165  return fs.mkdir(target, { recursive: true })166    .then(() => git(cloneArgs.concat(lp)))167    .then(() => git(['init']))168    .then(() => git(['checkout', ref]))169    .then(() => updateSubmodules(target, opts))170    .then(() => git(['rev-parse', '--revs-only', 'HEAD']))171    .then(({ stdout }) => stdout.trim())172}173