fix(packageRelativePath): fix 'where' for file deps

Fix 'where' for file deps. It makes more sense for the 'where' to be the 
directory the file is in (and was possibly built in) than it being the 
file itself, having no use whatsoever.

See https://npm.community/t/3364

lib/install/deps.js

@@ -190,10 +190,15 @@ function removeObsoleteDep (child, log) {
 function packageRelativePath (tree) {
   if (!tree) return ''
   var requested = tree.package._requested || {}
-  var isLocal = requested.type === 'directory' || requested.type === 'file'
-  return isLocal ? requested.fetchSpec
-    : (tree.isLink || tree.isInLink) && !preserveSymlinks() ? tree.realpath
-      : tree.path
+  if (requested.type === 'directory') {
+    return requested.fetchSpec
+  } else if (requested.type === 'file') {
+    return path.dirname(requested.fetchSpec)
+  } else if ((tree.isLink || tree.isInLink) && !preserveSymlinks()) {
+    return tree.realpath
+  } else {
+    return tree.path
+  }
 }
 
 function matchingDep (tree, name) {

test/tap/install-local-from-local.js

@@ -0,0 +1,77 @@
+'use strict'
+var path = require('path')
+var fs = require('graceful-fs')
+var test = require('tap').test
+var common = require('../common-tap.js')
+var Tacks = require('tacks')
+var Dir = Tacks.Dir
+var File = Tacks.File
+
+var testdir = path.join(__dirname, path.basename(__filename, '.js'))
+var cwd = path.join(testdir, '3')
+
+var fixture = new Tacks(Dir({
+  '1': Dir({
+    '1-1.0.0.tgz': File(Buffer.from(
+      '1f8b08000000000000032b484cce4e4c4fd52f80d07a59c5f9790c540606' +
+      '06066626260ad8c4c1c0d85c81c1d8d4ccc0d0d0cccc00a80ec830353103' +
+      'd2d4760836505a5c925804740aa5e640bca200a78708a856ca4bcc4d55b2' +
+      '523254d2512a4b2d2acecccf03f1f40cf40c946ab906da79a360148c8251' +
+      '300a6804007849dfdf00080000',
+      'hex'
+    ))
+  }),
+  '2': Dir({
+    '2-1.0.0.tgz': File(Buffer.from(
+      '1f8b0800000000000003ed8f3d0e83300c8599394594b90d36840cdc2602' +
+      '17d19f80087468c5ddeb14a9135b91aa4af996e73c3f47f660eb8b6d291b' +
+      '565567dfbb646700c0682db6fc00ea5c24456900d118e01c17a52e58f75e' +
+      '648bd94f76e455befd67bd457cf44f78a64248676f242b21737908cf3b8d' +
+      'beeb5d70508182d56d6820d790ab3bf2dc0a83ec62489dba2b554a6598e1' +
+      'f13da1a6f62139b0a44bfaeb0b23914824b2c50b8b5b623100080000',
+      'hex'
+    ))
+  }),
+  '3': Dir({
+    'package.json': File({
+      name: '3',
+      version: '1.0.0',
+      dependencies: {
+        '2': '../2/2-1.0.0.tgz'
+      }
+    })
+  })
+}))
+
+function setup () {
+  fixture.create(testdir)
+}
+
+function cleanup () {
+  fixture.remove(testdir)
+}
+
+test('setup', function (t) {
+  cleanup()
+  setup()
+  t.end()
+})
+
+test('installing local package with local dependency', function (t) {
+  common.npm(
+    ['install'],
+    {cwd: cwd},
+    function (er, code, stdout, stderr) {
+      t.is(code, 0, 'no error code')
+      t.is(stderr, '', 'no error output')
+      t.ok(fs.existsSync(path.join(cwd, 'node_modules', '2')), 'installed direct dep')
+      t.ok(fs.existsSync(path.join(cwd, 'node_modules', '1')), 'installed indirect dep')
+      t.end()
+    }
+  )
+})
+
+test('cleanup', function (t) {
+  cleanup()
+  t.end()
+})