From f3d8db491bf781b29c82e1aa86ef5272282f8d96 Mon Sep 17 00:00:00 2001
From: Yousef El-Dardiry <yousefdardiry@gmail.com>
Date: Tue, 15 Jun 2021 16:36:22 +0200
Subject: [PATCH] implement hasAttribute

---
 src/types/YXmlElement.js | 13 +++++++++++++
 tests/y-xml.tests.js     | 17 +++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/src/types/YXmlElement.js b/src/types/YXmlElement.js
index b3ce6ef9..a0369c92 100644
--- a/src/types/YXmlElement.js
+++ b/src/types/YXmlElement.js
@@ -3,6 +3,7 @@ import {
   YXmlFragment,
   transact,
   typeMapDelete,
+  typeMapHas,
   typeMapSet,
   typeMapGet,
   typeMapGetAll,
@@ -160,6 +161,18 @@ export class YXmlElement extends YXmlFragment {
     return /** @type {any} */ (typeMapGet(this, attributeName))
   }
 
+  /**
+   * Returns whether an attribute exists
+   *
+   * @param {String} attributeName The attribute name to check for existence.
+   * @return {boolean} whether the attribute exists.
+   *
+   * @public
+   */
+   hasAttribute (attributeName) {
+    return /** @type {any} */ (typeMapHas(this, attributeName))
+  }
+
   /**
    * Returns all attribute name/value pairs in a JSON Object.
    *
diff --git a/tests/y-xml.tests.js b/tests/y-xml.tests.js
index 31513091..2a97801c 100644
--- a/tests/y-xml.tests.js
+++ b/tests/y-xml.tests.js
@@ -15,6 +15,23 @@ export const testSetProperty = tc => {
   compare(users)
 }
 
+/**
+ * @param {t.TestCase} tc
+ */
+ export const testHasProperty = tc => {
+  const { testConnector, users, xml0, xml1 } = init(tc, { users: 2 })
+  xml0.setAttribute('height', '10')
+  t.assert(xml0.hasAttribute('height'), 'Simple set+has works')
+  testConnector.flushAllMessages()
+  t.assert(xml1.hasAttribute('height'), 'Simple set+has works (remote)')
+
+  xml0.removeAttribute('height')
+  t.assert(!xml0.hasAttribute('height'), 'Simple set+remove+has works')
+  testConnector.flushAllMessages()
+  t.assert(!xml1.hasAttribute('height'), 'Simple set+remove+has works (remote)')
+  compare(users)
+}
+
 /**
  * @param {t.TestCase} tc
  */