fix(dropdowns): compose onKeyDown handler for multiselect

packages/dropdowns/.size-snapshot.json

@@ -1,20 +1,20 @@
 {
   "index.cjs.js": {
-    "bundled": 90488,
-    "minified": 55054,
-    "gzipped": 11734
+    "bundled": 90578,
+    "minified": 55125,
+    "gzipped": 11739
   },
   "index.esm.js": {
-    "bundled": 84138,
-    "minified": 49609,
-    "gzipped": 11371,
+    "bundled": 84209,
+    "minified": 49661,
+    "gzipped": 11380,
     "treeshaked": {
       "rollup": {
-        "code": 32969,
+        "code": 33010,
         "import_statements": 794
       },
       "webpack": {
-        "code": 43980
+        "code": 44045
       }
     }
   }

packages/dropdowns/src/elements/Multiselect/Multiselect.spec.tsx

@@ -5,7 +5,7 @@
  * found at http://www.apache.org/licenses/LICENSE-2.0.
  */
 
-import React from 'react';
+import React, { useState, useEffect } from 'react';
 import userEvent from '@testing-library/user-event';
 import { render, fireEvent, renderRtl, act } from 'garden-test-utils';
 import { Dropdown, Multiselect, Field, Menu, Item, Label, PreviousItem } from '../..';
@@ -186,6 +186,70 @@ describe('Multiselect', () => {
     expect(icon).toHaveStyleRule('height', '16px');
   });
 
+  it('composes onKeyDown handler', () => {
+    const onKeyDown = jest.fn();
+    const EVERLASTING_WINGED = 'Everlasting winged';
+    const options = ['Celosia', 'Dusty miller', EVERLASTING_WINGED];
+
+    const Example = () => {
+      const [inputValue, setInputValue] = useState('');
+      const [matchingOptions, setMatchingOptions] = useState(options);
+      const [selectedItems, setSelectedItems] = useState([options[0], options[1]]);
+
+      useEffect(() => {
+        const matchedOptions = options.filter(
+          option => option.trim().toLowerCase().indexOf(inputValue.trim().toLowerCase()) !== -1
+        );
+
+        setMatchingOptions(matchedOptions);
+      }, [inputValue]);
+
+      return (
+        <Dropdown
+          inputValue={inputValue}
+          selectedItems={selectedItems}
+          onSelect={setSelectedItems}
+          onInputValueChange={setInputValue}
+        >
+          <Field>
+            <Label>Seeds</Label>
+            <Multiselect
+              onKeyDown={onKeyDown}
+              renderItem={({ value, removeValue }) => (
+                <div>
+                  {value}
+                  <button onClick={removeValue} tabIndex={-1}>
+                    Remove
+                  </button>
+                </div>
+              )}
+            />
+          </Field>
+          <Menu>
+            {matchingOptions.map((option: string) => (
+              <Item key={option} value={option}>
+                <span>{option}</span>
+              </Item>
+            ))}
+          </Menu>
+        </Dropdown>
+      );
+    };
+
+    const { getByRole, queryByRole, queryAllByLabelText } = render(<Example />);
+    const combobox = getByRole('combobox');
+    const multiselect = queryAllByLabelText('Seeds')[0];
+    const addedOption = () => queryByRole('option', { name: new RegExp(EVERLASTING_WINGED, 'u') });
+
+    expect(addedOption()).not.toBeInTheDocument();
+
+    userEvent.type(multiselect, EVERLASTING_WINGED);
+    userEvent.type(combobox, '{enter}');
+
+    expect(addedOption()).toBeInTheDocument();
+    expect(onKeyDown).toHaveBeenCalledTimes(EVERLASTING_WINGED.length + 1);
+  });
+
   describe('Interaction', () => {
     it('opens on click', () => {
       const { getByTestId } = render(

packages/dropdowns/src/elements/Multiselect/Multiselect.tsx

@@ -82,6 +82,7 @@ export const Multiselect = React.forwardRef<HTMLDivElement, IMultiselectProps>(
       renderShowMore,
       inputRef: externalInputRef = null,
       start,
+      onKeyDown,
       ...props
     },
     ref
@@ -164,14 +165,14 @@ export const Multiselect = React.forwardRef<HTMLDivElement, IMultiselectProps>(
     const { type, ...selectProps } = getToggleButtonProps(
       getRootProps({
         tabIndex: props.disabled ? undefined : -1,
-        onKeyDown: (e: React.KeyboardEvent<HTMLElement>) => {
+        onKeyDown: composeEventHandlers(onKeyDown, (e: React.KeyboardEvent<HTMLElement>) => {
           if (isOpen) {
             (e.nativeEvent as any).preventDownshiftDefault = true;
           } else if (!inputValue && e.keyCode === KEY_CODES.HOME) {
             setFocusedItem(selectedItems[0]);
             e.preventDefault();
           }
-        },
+        }),
         onFocus: () => {
           setIsFocused(true);
         },