simple-squiggle

A restricted subset of Squiggle
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which.js (3163B)

      1 const isWindows = process.platform === 'win32' ||
      2     process.env.OSTYPE === 'cygwin' ||
      3     process.env.OSTYPE === 'msys'
      4 
      5 const path = require('path')
      6 const COLON = isWindows ? ';' : ':'
      7 const isexe = require('isexe')
      8 
      9 const getNotFoundError = (cmd) =>
     10   Object.assign(new Error(`not found: ${cmd}`), { code: 'ENOENT' })
     11 
     12 const getPathInfo = (cmd, opt) => {
     13   const colon = opt.colon || COLON
     14 
     15   // If it has a slash, then we don't bother searching the pathenv.
     16   // just check the file itself, and that's it.
     17   const pathEnv = cmd.match(/\//) || isWindows && cmd.match(/\\/) ? ['']
     18     : (
     19       [
     20         // windows always checks the cwd first
     21         ...(isWindows ? [process.cwd()] : []),
     22         ...(opt.path || process.env.PATH ||
     23           /* istanbul ignore next: very unusual */ '').split(colon),
     24       ]
     25     )
     26   const pathExtExe = isWindows
     27     ? opt.pathExt || process.env.PATHEXT || '.EXE;.CMD;.BAT;.COM'
     28     : ''
     29   const pathExt = isWindows ? pathExtExe.split(colon) : ['']
     30 
     31   if (isWindows) {
     32     if (cmd.indexOf('.') !== -1 && pathExt[0] !== '')
     33       pathExt.unshift('')
     34   }
     35 
     36   return {
     37     pathEnv,
     38     pathExt,
     39     pathExtExe,
     40   }
     41 }
     42 
     43 const which = (cmd, opt, cb) => {
     44   if (typeof opt === 'function') {
     45     cb = opt
     46     opt = {}
     47   }
     48   if (!opt)
     49     opt = {}
     50 
     51   const { pathEnv, pathExt, pathExtExe } = getPathInfo(cmd, opt)
     52   const found = []
     53 
     54   const step = i => new Promise((resolve, reject) => {
     55     if (i === pathEnv.length)
     56       return opt.all && found.length ? resolve(found)
     57         : reject(getNotFoundError(cmd))
     58 
     59     const ppRaw = pathEnv[i]
     60     const pathPart = /^".*"$/.test(ppRaw) ? ppRaw.slice(1, -1) : ppRaw
     61 
     62     const pCmd = path.join(pathPart, cmd)
     63     const p = !pathPart && /^\.[\\\/]/.test(cmd) ? cmd.slice(0, 2) + pCmd
     64       : pCmd
     65 
     66     resolve(subStep(p, i, 0))
     67   })
     68 
     69   const subStep = (p, i, ii) => new Promise((resolve, reject) => {
     70     if (ii === pathExt.length)
     71       return resolve(step(i + 1))
     72     const ext = pathExt[ii]
     73     isexe(p + ext, { pathExt: pathExtExe }, (er, is) => {
     74       if (!er && is) {
     75         if (opt.all)
     76           found.push(p + ext)
     77         else
     78           return resolve(p + ext)
     79       }
     80       return resolve(subStep(p, i, ii + 1))
     81     })
     82   })
     83 
     84   return cb ? step(0).then(res => cb(null, res), cb) : step(0)
     85 }
     86 
     87 const whichSync = (cmd, opt) => {
     88   opt = opt || {}
     89 
     90   const { pathEnv, pathExt, pathExtExe } = getPathInfo(cmd, opt)
     91   const found = []
     92 
     93   for (let i = 0; i < pathEnv.length; i ++) {
     94     const ppRaw = pathEnv[i]
     95     const pathPart = /^".*"$/.test(ppRaw) ? ppRaw.slice(1, -1) : ppRaw
     96 
     97     const pCmd = path.join(pathPart, cmd)
     98     const p = !pathPart && /^\.[\\\/]/.test(cmd) ? cmd.slice(0, 2) + pCmd
     99       : pCmd
    100 
    101     for (let j = 0; j < pathExt.length; j ++) {
    102       const cur = p + pathExt[j]
    103       try {
    104         const is = isexe.sync(cur, { pathExt: pathExtExe })
    105         if (is) {
    106           if (opt.all)
    107             found.push(cur)
    108           else
    109             return cur
    110         }
    111       } catch (ex) {}
    112     }
    113   }
    114 
    115   if (opt.all && found.length)
    116     return found
    117 
    118   if (opt.nothrow)
    119     return null
    120 
    121   throw getNotFoundError(cmd)
    122 }
    123 
    124 module.exports = which
    125 which.sync = whichSync