1 files changed, 163 insertions, 0 deletions
diff --git a/lib/commands/help.js b/lib/commands/help.js
new file mode 100644
index 000000000..5b6a87bfc
--- /dev/null
+++ b/lib/commands/help.js
@@ -0,0 +1,163 @@
+const { spawn } = require('child_process')
+const path = require('path')
+const openUrl = require('../utils/open-url.js')
+const { promisify } = require('util')
+const glob = promisify(require('glob'))
+const localeCompare = require('@isaacs/string-locale-compare')('en')
+
+const BaseCommand = require('../base-command.js')
+
+// Strips out the number from foo.7 or foo.7. or foo.7.tgz
+// We don't currently compress our man pages but if we ever did this would
+// seemlessly continue supporting it
+const manNumberRegex = /\.(\d+)(\.[^/\\]*)?$/
+
+class Help extends BaseCommand {
+  /* istanbul ignore next - see test/lib/load-all-commands.js */
+  static get description () {
+    return 'Get help on npm'
+  }
+
+  /* istanbul ignore next - see test/lib/load-all-commands.js */
+  static get name () {
+    return 'help'
+  }
+
+  /* istanbul ignore next - see test/lib/load-all-commands.js */
+  static get usage () {
+    return ['<term> [<terms..>]']
+  }
+
+  /* istanbul ignore next - see test/lib/load-all-commands.js */
+  static get params () {
+    return ['viewer']
+  }
+
+  async completion (opts) {
+    if (opts.conf.argv.remain.length > 2)
+      return []
+    const g = path.resolve(__dirname, '../man/man[0-9]/*.[0-9]')
+    const files = await glob(g)
+
+    return Object.keys(files.reduce(function (acc, file) {
+      file = path.basename(file).replace(/\.[0-9]+$/, '')
+      file = file.replace(/^npm-/, '')
+      acc[file] = true
+      return acc
+    }, { help: true }))
+  }
+
+  async exec (args) {
+    // By default we search all of our man subdirectories, but if the user has
+    // asked for a specific one we limit the search to just there
+    let manSearch = 'man*'
+    if (/^\d+$/.test(args[0]))
+      manSearch = `man${args.shift()}`
+
+    if (!args.length)
+      return this.npm.output(await this.npm.usage)
+
+    // npm help foo bar baz: search topics
+    if (args.length > 1)
+      return this.helpSearch(args)
+
+    let section = this.npm.deref(args[0]) || args[0]
+
+    // support `npm help package.json`
+    section = section.replace('.json', '-json')
+
+    const manroot = path.resolve(__dirname, '..', 'man')
+    // find either section.n or npm-section.n
+    const f = `${manroot}/${manSearch}/?(npm-)${section}.[0-9]*`
+    let mans = await glob(f)
+    mans = mans.sort((a, b) => {
+      // Because of the glob we know the manNumberRegex will pass
+      const aManNumber = a.match(manNumberRegex)[1]
+      const bManNumber = b.match(manNumberRegex)[1]
+
+      // man number sort first so that 1 aka commands are preferred
+      if (aManNumber !== bManNumber)
+        return aManNumber - bManNumber
+
+      return localeCompare(a, b)
+    })
+    const man = mans[0]
+
+    if (man)
+      await this.viewMan(man)
+    else
+      return this.helpSearch(args)
+  }
+
+  helpSearch (args) {
+    return new Promise((resolve, reject) => {
+      this.npm.commands['help-search'](args, (err) => {
+        // This would only error if args was empty, which it never is
+        /* istanbul ignore next */
+        if (err)
+          return reject(err)
+
+        resolve()
+      })
+    })
+  }
+
+  async viewMan (man) {
+    const env = {}
+    Object.keys(process.env).forEach(function (i) {
+      env[i] = process.env[i]
+    })
+    const viewer = this.npm.config.get('viewer')
+
+    const opts = {
+      env,
+      stdio: 'inherit',
+    }
+
+    let bin = 'man'
+    const args = []
+    switch (viewer) {
+      case 'woman':
+        bin = 'emacsclient'
+        args.push('-e', `(woman-find-file '${man}')`)
+        break
+
+      case 'browser':
+        await openUrl(this.npm, this.htmlMan(man), 'help available at the following URL')
+        return
+
+      default:
+        args.push(man)
+        break
+    }
+
+    const proc = spawn(bin, args, opts)
+    return new Promise((resolve, reject) => {
+      proc.on('exit', (code) => {
+        if (code)
+          return reject(new Error(`help process exited with code: ${code}`))
+
+        return resolve()
+      })
+    })
+  }
+
+  // Returns the path to the html version of the man page
+  htmlMan (man) {
+    let sect = man.match(manNumberRegex)[1]
+    const f = path.basename(man).replace(manNumberRegex, '')
+    switch (sect) {
+      case '1':
+        sect = 'commands'
+        break
+      case '5':
+        sect = 'configuring-npm'
+        break
+      case '7':
+        sect = 'using-npm'
+        break
+    }
+    return 'file://' + path.resolve(__dirname, '..', 'docs', 'output', sect, f + '.html')
+  }
+}
+module.exports = Help