help: show usage when help-search finds no results

Fix #1655

Author: isaacs

lib/help-search.js

@@ -7,10 +7,14 @@ const output = require('./utils/output.js')
 const usageUtil = require('./utils/usage.js')
 const { promisify } = require('util')
 const readFile = promisify(fs.readFile)
+const didYouMean = require('./utils/did-you-mean.js')
+const { cmdList } = require('./utils/cmd-list.js')
 
 const usage = usageUtil('help-search', 'npm help-search <text>')
 const completion = require('./utils/completion/none.js')
 
+const npmUsage = require('./utils/npm-usage.js')
+
 const cmd = (args, cb) => helpSearch(args).then(() => cb()).catch(cb)
 
 const helpSearch = async args => {
@@ -26,7 +30,13 @@ const helpSearch = async args => {
 
   const data = await readFiles(files)
   const results = await searchFiles(args, data, files)
-  output(formatResults(args, results))
+  const formatted = formatResults(args, results)
+  if (!formatted.trim()) {
+    npmUsage(false)
+  } else {
+    output(formatted)
+    output(didYouMean(args[0], cmdList))
+  }
 }
 
 const readFiles = async files => {

lib/help.js

@@ -6,15 +6,13 @@ help.completion = function (opts, cb) {
   getSections(cb)
 }
 
+const npmUsage = require('./utils/npm-usage.js')
 var path = require('path')
 var spawn = require('./utils/spawn')
 var npm = require('./npm.js')
 var log = require('npmlog')
 var openUrl = require('./utils/open-url')
 var glob = require('glob')
-var didYouMean = require('./utils/did-you-mean')
-var cmdList = require('./utils/cmd-list').cmdList
-var commands = cmdList
 var output = require('./utils/output.js')
 
 const usage = require('./utils/usage.js')
@@ -42,7 +40,8 @@ function help (args, cb) {
   // npm help <noargs>:  show basic usage
   if (!section) {
     var valid = argv[0] === 'help' ? 0 : 1
-    return npmUsage(valid, cb)
+    npmUsage(argv[0] === 'help')
+    return cb()
   }
 
   // npm <command> -h: show command usage
@@ -161,83 +160,6 @@ function htmlMan (man) {
   return 'file://' + path.resolve(__dirname, '..', 'docs', 'public', sect, f, 'index.html')
 }
 
-function npmUsage (valid, cb) {
-  npm.config.set('loglevel', 'silent')
-  log.level = 'silent'
-  output(`
-Usage: npm <command>
-
-npm install        install all the dependencies in your project
-npm install <foo>  add the <foo> dependency to your project
-npm test           run this project's tests
-npm run <foo>      run the script named <foo>
-npm <command> -h   quick help on <command>
-npm -l             display usage info for all commands
-npm help <term>    search for help on <term>
-npm help npm       more involved overview
-
-All commands:
-${npm.config.get('long') ? usages() : ('\n    ' + wrap(commands))}
-
-Specify configs in the ini-formatted file:
-    ${npm.config.get('userconfig')}
-or on the command line via: npm <command> --key=value
-
-More configuration info: npm help config
-Configuration fields: npm help 7 config
-
-npm@${npm.version} ${path.dirname(__dirname)}
-`)
-
-  if (npm.argv.length > 1) {
-    output(didYouMean(npm.argv[1], commands))
-  }
-
-  cb(valid)
-}
-
-function usages () {
-  // return a string of <command>: <usage>
-  var maxLen = 0
-  return commands.reduce(function (set, c) {
-    set.push([c, require(`./${npm.deref(c)}.js`).usage || ''])
-    maxLen = Math.max(maxLen, c.length)
-    return set
-  }, []).sort((a, b) => {
-    return a[0].localeCompare(b[0])
-  }).map(function (item) {
-    var c = item[0]
-    var usage = item[1]
-    return '\n    ' +
-      c + (new Array(maxLen - c.length + 2).join(' ')) +
-      (usage.split('\n').join('\n' + (new Array(maxLen + 6).join(' '))))
-  }).join('\n')
-}
-
-function wrap (arr) {
-  var out = ['']
-  var l = 0
-  var line
-
-  line = process.stdout.columns
-  if (!line) {
-    line = 60
-  } else {
-    line = Math.min(60, Math.max(line - 16, 24))
-  }
-
-  arr.sort(function (a, b) { return a < b ? -1 : 1 })
-    .forEach(function (c) {
-      if (out[l].length + c.length + 2 < line) {
-        out[l] += ', ' + c
-      } else {
-        out[l++] += ','
-        out[l] = c
-      }
-    })
-  return out.join('\n    ').substr(2)
-}
-
 function getSections (cb) {
   var g = path.resolve(__dirname, '../man/man[0-9]/*.[0-9]')
   glob(g, function (er, files) {

lib/utils/npm-usage.js

@@ -0,0 +1,85 @@
+const npm = require('../npm.js')
+const didYouMean = require('./did-you-mean.js')
+const { dirname } = require('path')
+const output = require('./output.js')
+const { cmdList } = require('./cmd-list')
+
+module.exports = (valid = true) => {
+  npm.config.set('loglevel', 'silent')
+  npm.log.level = 'silent'
+  output(`
+Usage: npm <command>
+
+npm install        install all the dependencies in your project
+npm install <foo>  add the <foo> dependency to your project
+npm test           run this project's tests
+npm run <foo>      run the script named <foo>
+npm <command> -h   quick help on <command>
+npm -l             display usage info for all commands
+npm help <term>    search for help on <term>
+npm help npm       more involved overview
+
+All commands:
+${npm.config.get('long') ? usages() : ('\n    ' + wrap(cmdList))}
+
+Specify configs in the ini-formatted file:
+    ${npm.config.get('userconfig')}
+or on the command line via: npm <command> --key=value
+
+More configuration info: npm help config
+Configuration fields: npm help 7 config
+
+npm@${npm.version} ${dirname(dirname(__dirname))}
+`)
+
+  if (npm.argv.length >= 1) {
+    output(didYouMean(npm.argv[0], cmdList))
+  }
+
+  if (!valid) {
+    process.exitCode = 1
+  }
+}
+
+const wrap = (arr) => {
+  var out = ['']
+  var l = 0
+  var line
+
+  line = process.stdout.columns
+  if (!line) {
+    line = 60
+  } else {
+    line = Math.min(60, Math.max(line - 16, 24))
+  }
+
+  arr.sort(function (a, b) { return a < b ? -1 : 1 })
+    .forEach(function (c) {
+      if (out[l].length + c.length + 2 < line) {
+        out[l] += ', ' + c
+      } else {
+        out[l++] += ','
+        out[l] = c
+      }
+    })
+  return out.join('\n    ').substr(2)
+}
+
+const usages = () => {
+  // return a string of <command>: <usage>
+  var maxLen = 0
+  return cmdList.reduce(function (set, c) {
+    set.push([c, require(`./${npm.deref(c)}.js`).usage || ''])
+    maxLen = Math.max(maxLen, c.length)
+    return set
+  }, []).sort((a, b) => {
+    return a[0].localeCompare(b[0])
+  }).map(function (item) {
+    var c = item[0]
+    var usage = item[1]
+    return '\n    ' +
+      c + (new Array(maxLen - c.length + 2).join(' ')) +
+      (usage.split('\n').join('\n' + (new Array(maxLen + 6).join(' '))))
+  }).join('\n')
+}
+