codekingpro/portable-devtools

1const { resolve, dirname } = require('path')
2const { lstat } = require('fs/promises')
3const throwNonEnoent = er => {
4  if (er.code !== 'ENOENT') {
5    throw er
6  }
7}
8
9const cmdShim = require('cmd-shim')
10const readCmdShim = require('read-cmd-shim')
11
12const fixBin = require('./fix-bin.js')
13
14// even in --force mode, we never create a shim over a shim we've
15// already created.  you can have multiple packages in a tree trying
16// to contend for the same bin, which creates a race condition and
17// nondeterminism.
18const seen = new Set()
19
20const failEEXIST = ({ to, from }) =>
21  Promise.reject(Object.assign(new Error('EEXIST: file already exists'), {
22    path: to,
23    dest: from,
24    code: 'EEXIST',
25  }))
26
27const handleReadCmdShimError = ({ er, from, to }) =>
28  er.code === 'ENOENT' ? null
29  : er.code === 'ENOTASHIM' ? failEEXIST({ from, to })
30  : Promise.reject(er)
31
32const SKIP = Symbol('skip - missing or already installed')
33const shimBin = ({ path, to, from, absFrom, force }) => {
34  const shims = [
35    to,
36    to + '.cmd',
37    to + '.ps1',
38  ]
39
40  for (const shim of shims) {
41    if (seen.has(shim)) {
42      return true
43    }
44    seen.add(shim)
45  }
46
47  return Promise.all([
48    ...shims,
49    absFrom,
50  ].map(f => lstat(f).catch(throwNonEnoent))).then((stats) => {
51    const [, , , stFrom] = stats
52    if (!stFrom) {
53      return SKIP
54    }
55
56    if (force) {
57      return false
58    }
59
60    return Promise.all(shims.map((s, i) => [s, stats[i]]).map(([s, st]) => {
61      if (!st) {
62        return false
63      }
64      return readCmdShim(s)
65        .then(target => {
66          target = resolve(dirname(to), target)
67          if (target.indexOf(resolve(path)) !== 0) {
68            return failEEXIST({ from, to, path })
69          }
70          return false
71        }, er => handleReadCmdShimError({ er, from, to }))
72    }))
73  })
74    .then(skip => skip !== SKIP && doShim(absFrom, to))
75}
76
77const doShim = (absFrom, to) =>
78  cmdShim(absFrom, to).then(() => fixBin(absFrom))
79
80const resetSeen = () => {
81  for (const p of seen) {
82    seen.delete(p)
83  }
84}
85
86module.exports = Object.assign(shimBin, { resetSeen })
87