Initial commit

node_modules/help-me/help-me.js

@@ -0,0 +1,134 @@
+'use strict'
+
+const fs = require('fs')
+const { PassThrough, Writable, pipeline } = require('stream')
+const process = require('process')
+const { join } = require('path')
+
+const defaults = {
+  ext: '.txt',
+  help: 'help'
+}
+
+function isDirectory (path) {
+  try {
+    const stat = fs.lstatSync(path)
+    return stat.isDirectory()
+  } catch (err) {
+    return false
+  }
+}
+
+function createDefaultStream () {
+  return new Writable({
+    write (chunk, encoding, callback) {
+      process.stdout.write(chunk, callback)
+    }
+  })
+}
+
+function helpMe (opts) {
+  opts = Object.assign({}, defaults, opts)
+
+  if (!opts.dir) {
+    throw new Error('missing dir')
+  }
+
+  if (!isDirectory(opts.dir)) {
+    throw new Error(`${opts.dir} is not a directory`)
+  }
+
+  return {
+    createStream: createStream,
+    toStdout: toStdout
+  }
+
+  function createStream (args) {
+    if (typeof args === 'string') {
+      args = args.split(' ')
+    } else if (!args || args.length === 0) {
+      args = [opts.help]
+    }
+
+    const out = new PassThrough()
+    const re = new RegExp(
+      args
+        .map(function (arg) {
+          return arg + '[a-zA-Z0-9]*'
+        })
+        .join('[ /]+')
+    )
+
+    if (process.platform === 'win32') {
+      opts.dir = opts.dir.split('\\').join('/')
+    }
+
+    fs.readdir(opts.dir, function (err, files) {
+      if (err) return out.emit('error', err)
+
+      const regexp = new RegExp('.*' + opts.ext + '$')
+      files = files
+        .filter(function (file) {
+          const matched = file.match(regexp)
+          return !!matched
+        })
+        .map(function (relative) {
+          return { file: join(opts.dir, relative), relative }
+        })
+        .filter(function (file) {
+          return file.relative.match(re)
+        })
+
+      if (files.length === 0) {
+        return out.emit('error', new Error('no such help file'))
+      } else if (files.length > 1) {
+        const exactMatch = files.find(
+          (file) => file.relative === `${args[0]}${opts.ext}`
+        )
+        if (!exactMatch) {
+          out.write('There are ' + files.length + ' help pages ')
+          out.write('that matches the given request, please disambiguate:\n')
+          files.forEach(function (file) {
+            out.write('  * ')
+            out.write(file.relative.replace(opts.ext, ''))
+            out.write('\n')
+          })
+          out.end()
+          return
+        }
+        files = [exactMatch]
+      }
+
+      pipeline(fs.createReadStream(files[0].file), out, () => {})
+    })
+
+    return out
+  }
+
+  function toStdout (args = [], opts) {
+    opts = opts || {}
+    const stream = opts.stream || createDefaultStream()
+    const _onMissingHelp = opts.onMissingHelp || onMissingHelp
+    return new Promise((resolve, reject) => {
+      createStream(args)
+        .on('error', (err) => {
+          _onMissingHelp(err, args, stream).then(resolve, reject)
+        })
+        .pipe(stream)
+        .on('close', resolve)
+        .on('end', resolve)
+    })
+  }
+
+  function onMissingHelp (_, args, stream) {
+    stream.write(`no such help file: ${args.join(' ')}.\n\n`)
+    return toStdout([], { stream, async onMissingHelp () {} })
+  }
+}
+
+function help (opts, args) {
+  return helpMe(opts).toStdout(args, opts)
+}
+
+module.exports = helpMe
+module.exports.help = help