From ed4d46fb594cca39ed1cb22d7419252aa89a90aa Mon Sep 17 00:00:00 2001
From: Robert Wagner <rwwagner90@gmail.com>
Date: Sat, 28 Sep 2019 12:46:32 -0400
Subject: [PATCH] Remove classes when set to false

Fixes #253
---
 src/js/tether.js         |  5 ++++-
 test/unit/tether.spec.js | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/src/js/tether.js b/src/js/tether.js
index f74710f1e..d112d57da 100644
--- a/src/js/tether.js
+++ b/src/js/tether.js
@@ -112,7 +112,10 @@ class TetherClass extends Evented {
 
   getClass(key = '') {
     const { classes } = this.options;
-    if (typeof classes !== 'undefined' && classes[key]) {
+    if (typeof classes !== 'undefined' && typeof classes[key] !== 'undefined') {
+      if (classes[key] === false) {
+        return '';
+      }
       return this.options.classes[key];
     } else if (this.options.classPrefix) {
       return `${this.options.classPrefix}-${key}`;
diff --git a/test/unit/tether.spec.js b/test/unit/tether.spec.js
index ef9611e2a..0193e5285 100644
--- a/test/unit/tether.spec.js
+++ b/test/unit/tether.spec.js
@@ -136,5 +136,39 @@ describe('Tether', () => {
       expect(element.classList.length, 'element - destroy sets classes back to initial state').toEqual(1);
       expect(target.classList.length, 'target - destroy sets classes back to initial state').toEqual(1);
     });
+
+    it('removes classes when false', () => {
+      expect(element.classList.length, 'element - only one class').toEqual(1);
+      expect(target.classList.length, 'target - only one class').toEqual(1);
+      const tether = new Tether({
+        element: '.element',
+        target: '.target',
+        attachment: 'top left',
+        targetAttachment: 'top right',
+        classes: {
+          element: false,
+          enabled: false,
+          target: false
+        }
+      });
+
+      tether.enable();
+
+      expect(element.classList.length, 'element - classes added').toEqual(10);
+      expect(element).not.toHaveClass('tether-element');
+      expect(element).not.toHaveClass('tether-enabled');
+
+      expect(target.classList.length, 'target - classes added').toEqual(10);
+      expect(target).not.toHaveClass('tether-target');
+      expect(element).not.toHaveClass('tether-enabled');
+
+      expect(tether.getClass('element')).toBe('');
+      expect(tether.getClass('target')).toBe('');
+
+      tether.destroy();
+
+      expect(element.classList.length, 'element - destroy sets classes back to initial state').toEqual(1);
+      expect(target.classList.length, 'target - destroy sets classes back to initial state').toEqual(1);
+    });
   });
 });