Attribute.isAttribute improvements

Author: jsumners

index.js

@@ -254,14 +254,36 @@ class Attribute {
   /**
    * Determine if an object represents an {@link Attribute}.
    *
-   * @param {object} item
+   * @param {object} attr The object to check. It can be an instance of
+   * {@link Attribute} or a plain JavaScript object that looks like an
+   * {@link Attribute} and can be passed to the constructor to create one.
    *
    * @returns {boolean}
    */
-  static isAttribute (item) {
-    // TODO: we might need to support a plain object that looks like
-    // an attribute object. The original code does.
-    return Object.prototype.toString.call(item) === '[object LdapAttribute]'
+  static isAttribute (attr) {
+    if (typeof attr !== 'object') {
+      return false
+    }
+
+    if (Object.prototype.toString.call(attr) === '[object LdapAttribute]') {
+      return true
+    }
+
+    const typeOk = typeof attr.type === 'string'
+    let valuesOk = Array.isArray(attr.values)
+    if (valuesOk === true) {
+      for (const val of attr.values) {
+        if (typeof val !== 'string' && Buffer.isBuffer(val) === false) {
+          valuesOk = false
+          break
+        }
+      }
+    }
+    if (typeOk === true && valuesOk === true) {
+      return true
+    }
+
+    return false
   }
 }
 

index.test.js

@@ -290,14 +290,53 @@ tap.test('#fromBer', t => {
   t.end()
 })
 
-tap.test('#isAttribute', async t => {
-  const isA = Attribute.isAttribute
-  t.notOk(isA(null))
-  t.notOk(isA('asdf'))
-  t.ok(isA(new Attribute({
-    type: 'foobar',
-    values: ['asdf']
-  })))
+tap.test('#isAttribute', t => {
+  t.test('rejects non-object', async t => {
+    t.equal(Attribute.isAttribute(42), false)
+  })
+
+  t.test('accepts Attribute instances', async t => {
+    const input = new Attribute({
+      type: 'cn',
+      values: ['foo']
+    })
+    t.equal(Attribute.isAttribute(input), true)
+  })
+
+  t.test('accepts attribute-like objects', async t => {
+    const input = {
+      type: 'cn',
+      values: [
+        'foo',
+        Buffer.from('bar')
+      ]
+    }
+    t.equal(Attribute.isAttribute(input), true)
+  })
+
+  t.test('rejects non-attribute-like objects', async t => {
+    let input = {
+      foo: 'foo',
+      values: 'bar'
+    }
+    t.equal(Attribute.isAttribute(input), false)
+
+    input = {
+      type: 'cn',
+      values: [42]
+    }
+    t.equal(Attribute.isAttribute(input), false)
+  })
+
+  // const isA = Attribute.isAttribute
+  // t.notOk(isA(null))
+  // t.notOk(isA('asdf'))
+  // t.ok(isA(new Attribute({
+  //   type: 'foobar',
+  //   values: ['asdf']
+  // })))
+
+  t.end()
 })
 
 tap.test('compare', async t => {

package.json

@@ -7,7 +7,7 @@
   "name": "@ldapjs/attribute",
   "homepage": "https://github.com/ldapjs/attribute",
   "description": "API for handling LDAP entry attributes",
-  "version": "1.0.0-rc.1",
+  "version": "1.0.0-rc.2",
   "license": "MIT",
   "repository": {
     "type": "git",