Add failing regression test for npm ls --depth=0

This test should turn green if read-installed is fixed and should
avoid regressions in the future.

This tests the cli, as it turned out that the programatical version
of npm has a bug where depth=0 is not working

test/tap/ls-depth-cli.js

@@ -0,0 +1,83 @@
+var common = require('../common-tap')
+  , test = require('tap').test
+  , path = require('path')
+  , spawn = require('child_process').spawn
+  , rimraf = require('rimraf')
+  , mkdirp = require('mkdirp')
+  , pkg = __dirname + '/ls-depth'
+  , cache = pkg + '/cache'
+  , tmp = pkg + '/tmp'
+  , node = process.execPath
+  , npm = path.resolve(__dirname, '../../cli.js')
+  , mr = require('npm-registry-mock')
+
+function run (command, t, cb) {
+  var c = ''
+    , child = spawn(node, command, {
+      cwd: pkg
+    })
+
+    child.stdout.on('data', function (chunk) {
+      c += chunk
+    })
+
+    child.stdout.on('end', function () {
+      if (test)
+        cb(t, c)
+      else
+        t.end()
+    })
+}
+
+function cleanup () {
+  rimraf.sync(pkg + '/cache')
+  rimraf.sync(pkg + '/tmp')
+  rimraf.sync(pkg + '/node_modules')
+}
+
+test('setup', function (t) {
+  cleanup()
+  mkdirp.sync(pkg + '/cache')
+  mkdirp.sync(pkg + '/tmp')
+  mr(common.port, function (s) {
+    run([npm, 'install', '--registry=' + common.registry], t, function (t, c) {
+      s.close()
+      t.end()
+    })
+  })
+})
+
+test('npm ls --depth=0', function (t) {
+  run([npm, 'ls', '--depth=0'], t, function (t, c) {
+    t.has(c, /test-package-with-one-dep@0\.0\.0/
+      , "output contains [email protected]")
+    t.doesNotHave(c, /test-package@0\.0\.0/
+      , "output not contains [email protected]")
+    t.end()
+  })
+})
+
+test('npm ls --depth=1', function (t) {
+  run([npm, 'ls', '--depth=1'], t, function (t, c) {
+    t.has(c, /test-package-with-one-dep@0\.0\.0/
+      , "output contains [email protected]")
+    t.has(c, /test-package@0\.0\.0/
+      , "output contains [email protected]")
+    t.end()
+  })
+})
+
+test('npm ls (no depth defined)', function (t) {
+  run([npm, 'ls'], t, function (t, c) {
+    t.has(c, /test-package-with-one-dep@0\.0\.0/
+      , "output contains [email protected]")
+    t.has(c, /test-package@0\.0\.0/
+      , "output contains [email protected]")
+    t.end()
+  })
+})
+
+test('cleanup', function (t) {
+  cleanup()
+  t.end()
+})

test/tap/ls-depth/package.json

@@ -0,0 +1,8 @@
+{
+  "author": "Rocko Artischocko",
+  "name": "ls-depth",
+  "version": "0.0.0",
+  "dependencies": {
+    "test-package-with-one-dep": "0.0.0"
+  }
+}