fix(Dropdown): disabled toggle (#1571)

* fix: Dropdown disabled toggle issue

This fix addresses the issue where Dropdown will be passed a
`disabled` prop, yet it is still clickable. This is due to context
being passed the user-defined `toggle` prop directly, rather than
our defined `this.toggle` function that includes a check for
`disabled`.

Fixes #1542

* fix: incorrect test assertion

In the previous implementation, Dropdown wasn't properly firing
the toggle function within Dropdown, so the assertion was written
down wrong to compensate for that.

src/Dropdown.js

@@ -52,10 +52,11 @@ class Dropdown extends React.Component {
 
   getContextValue() {
     return {
-      toggle: this.props.toggle,
+      toggle: this.toggle,
       isOpen: this.props.isOpen,
       direction: (this.props.direction === 'down' && this.props.dropup) ? 'up' : this.props.direction,
       inNavbar: this.props.inNavbar,
+      disabled: this.props.disabled
     };
   }
 

src/DropdownContext.js

@@ -7,6 +7,7 @@ import React from 'react';
  *  isOpen: PropTypes.bool.isRequired,
  *  direction: PropTypes.oneOf(['up', 'down', 'left', 'right']).isRequired,
  *  inNavbar: PropTypes.bool.isRequired,
+ *  disabled: PropTypes.bool
  * }
  */
 export const DropdownContext = React.createContext({});

src/DropdownToggle.js

@@ -33,7 +33,7 @@ class DropdownToggle extends React.Component {
   }
 
   onClick(e) {
-    if (this.props.disabled) {
+    if (this.props.disabled || this.context.disabled) {
       e.preventDefault();
       return;
     }

src/__tests__/Dropdown.spec.js

@@ -735,7 +735,7 @@ describe('Dropdown', () => {
 
       wrapper.find('#first').hostNodes().simulate('keydown', { which: keyCodes.space });
 
-      expect(Dropdown.prototype.toggle.mock.calls.length).toBe(0);
+      expect(Dropdown.prototype.toggle.mock.calls.length).toBe(1);
       expect(click.mock.calls.length).toBe(1);
 
       wrapper.detach();
@@ -761,7 +761,7 @@ describe('Dropdown', () => {
 
       wrapper.find('#first').hostNodes().simulate('keydown', { which: keyCodes.space });
 
-      expect(Dropdown.prototype.toggle.mock.calls.length).toBe(0);
+      expect(Dropdown.prototype.toggle.mock.calls.length).toBe(1);
       expect(click.mock.calls.length).toBe(1);
 
       wrapper.detach();