Make form components uncontrollable

packages/@headlessui-react/src/components/combobox/combobox.test.tsx

@@ -901,6 +901,134 @@ describe('Rendering', () => {
     // Verify that the third combobox option is active
     assertActiveComboboxOption(options[2])
   })
+
+  describe('Uncontrolled', () => {
+    it('should be possible to use in an uncontrolled way', async () => {
+      let handleSubmission = jest.fn()
+
+      render(
+        <form
+          onSubmit={(e) => {
+            e.preventDefault()
+            handleSubmission(Object.fromEntries(new FormData(e.target as HTMLFormElement)))
+          }}
+        >
+          <Combobox name="assignee">
+            <Combobox.Input onChange={NOOP} />
+            <Combobox.Button>Trigger</Combobox.Button>
+            <Combobox.Options>
+              <Combobox.Option value="alice">Alice</Combobox.Option>
+              <Combobox.Option value="bob">Bob</Combobox.Option>
+              <Combobox.Option value="charlie">Charlie</Combobox.Option>
+            </Combobox.Options>
+          </Combobox>
+          <button id="submit">submit</button>
+        </form>
+      )
+
+      await click(document.getElementById('submit'))
+
+      // No values
+      expect(handleSubmission).toHaveBeenLastCalledWith({})
+
+      // Open combobox
+      await click(getComboboxButton())
+
+      // Choose alice
+      await click(getComboboxOptions()[0])
+
+      // Submit
+      await click(document.getElementById('submit'))
+
+      // Alice should be submitted
+      expect(handleSubmission).toHaveBeenLastCalledWith({ assignee: 'alice' })
+
+      // Open combobox
+      await click(getComboboxButton())
+
+      // Choose charlie
+      await click(getComboboxOptions()[2])
+
+      // Submit
+      await click(document.getElementById('submit'))
+
+      // Charlie should be submitted
+      expect(handleSubmission).toHaveBeenLastCalledWith({ assignee: 'charlie' })
+    })
+
+    it('should be possible to provide a default value', async () => {
+      let handleSubmission = jest.fn()
+
+      render(
+        <form
+          onSubmit={(e) => {
+            e.preventDefault()
+            handleSubmission(Object.fromEntries(new FormData(e.target as HTMLFormElement)))
+          }}
+        >
+          <Combobox name="assignee" defaultValue="bob">
+            <Combobox.Input onChange={NOOP} />
+            <Combobox.Button>Trigger</Combobox.Button>
+            <Combobox.Options>
+              <Combobox.Option value="alice">Alice</Combobox.Option>
+              <Combobox.Option value="bob">Bob</Combobox.Option>
+              <Combobox.Option value="charlie">Charlie</Combobox.Option>
+            </Combobox.Options>
+          </Combobox>
+          <button id="submit">submit</button>
+        </form>
+      )
+
+      await click(document.getElementById('submit'))
+
+      // Bob is the defaultValue
+      expect(handleSubmission).toHaveBeenLastCalledWith({ assignee: 'bob' })
+
+      // Open combobox
+      await click(getComboboxButton())
+
+      // Choose alice
+      await click(getComboboxOptions()[0])
+
+      // Submit
+      await click(document.getElementById('submit'))
+
+      // Alice should be submitted
+      expect(handleSubmission).toHaveBeenLastCalledWith({ assignee: 'alice' })
+    })
+
+    it('should still call the onChange listeners when choosing new values', async () => {
+      let handleChange = jest.fn()
+
+      render(
+        <Combobox name="assignee" onChange={handleChange}>
+          <Combobox.Input onChange={NOOP} />
+          <Combobox.Button>Trigger</Combobox.Button>
+          <Combobox.Options>
+            <Combobox.Option value="alice">Alice</Combobox.Option>
+            <Combobox.Option value="bob">Bob</Combobox.Option>
+            <Combobox.Option value="charlie">Charlie</Combobox.Option>
+          </Combobox.Options>
+        </Combobox>
+      )
+
+      // Open combobox
+      await click(getComboboxButton())
+
+      // Choose alice
+      await click(getComboboxOptions()[0])
+
+      // Open combobox
+      await click(getComboboxButton())
+
+      // Choose bob
+      await click(getComboboxOptions()[1])
+
+      // Change handler should have been called twice
+      expect(handleChange).toHaveBeenNthCalledWith(1, 'alice')
+      expect(handleChange).toHaveBeenNthCalledWith(2, 'bob')
+    })
+  })
 })
 
 describe('Rendering composition', () => {

packages/@headlessui-react/src/components/combobox/combobox.tsx

@@ -40,6 +40,7 @@ import { Hidden, Features as HiddenFeatures } from '../../internal/hidden'
 import { useOpenClosed, State, OpenClosedProvider } from '../../internal/open-closed'
 
 import { Keys } from '../keyboard'
+import { useControllable } from '../../hooks/use-controllable'
 
 enum ComboboxState {
   Open,
@@ -301,6 +302,7 @@ interface ComboboxRenderPropArg<T> {
   disabled: boolean
   activeIndex: number | null
   activeOption: T | null
+  value: T
 }
 
 let ComboboxRoot = forwardRefWithAs(function Combobox<
@@ -311,10 +313,11 @@ let ComboboxRoot = forwardRefWithAs(function Combobox<
   props: Props<
     TTag,
     ComboboxRenderPropArg<TType>,
-    'value' | 'onChange' | 'disabled' | 'name' | 'nullable' | 'multiple' | 'by'
+    'value' | 'defaultValue' | 'onChange' | 'by' | 'disabled' | 'name' | 'nullable' | 'multiple'
   > & {
-    value: TType
-    onChange(value: TType): void
+    value?: TType
+    defaultValue?: TType
+    onChange?(value: TType): void
     by?: (keyof TActualType & string) | ((a: TActualType, z: TActualType) => boolean)
     disabled?: boolean
     __demoMode?: boolean
@@ -325,16 +328,18 @@ let ComboboxRoot = forwardRefWithAs(function Combobox<
   ref: Ref<TTag>
 ) {
   let {
+    value: controlledValue,
+    defaultValue,
+    onChange: controlledOnChange,
     name,
-    value,
-    onChange: theirOnChange,
     by = (a, z) => a === z,
     disabled = false,
     __demoMode = false,
     nullable = false,
     multiple = false,
     ...theirProps
   } = props
+  let [value, theirOnChange] = useControllable(controlledValue, controlledOnChange, defaultValue)
 
   let [state, dispatch] = useReducer(stateReducer, {
     dataRef: createRef(),
@@ -430,8 +435,9 @@ let ComboboxRoot = forwardRefWithAs(function Combobox<
         data.activeOptionIndex === null
           ? null
           : (data.options[data.activeOptionIndex].dataRef.current.value as TType),
+      value,
     }),
-    [data, disabled]
+    [data, disabled, value]
   )
 
   let syncInputValue = useCallback(() => {
@@ -495,7 +501,7 @@ let ComboboxRoot = forwardRefWithAs(function Combobox<
   let onChange = useEvent((value: unknown) => {
     return match(data.mode, {
       [ValueMode.Single]() {
-        return theirOnChange(value as TType)
+        return theirOnChange?.(value as TType)
       },
       [ValueMode.Multi]() {
         let copy = (data.value as TActualType[]).slice()
@@ -507,7 +513,7 @@ let ComboboxRoot = forwardRefWithAs(function Combobox<
           copy.splice(idx, 1)
         }
 
-        return theirOnChange(copy as unknown as TType)
+        return theirOnChange?.(copy as unknown as TType)
       },
     })
   })

packages/@headlessui-react/src/components/listbox/listbox.test.tsx

@@ -719,6 +719,131 @@ describe('Rendering', () => {
     // Verify that the third menu item is active
     assertActiveListboxOption(options[2])
   })
+
+  describe('Uncontrolled', () => {
+    it('should be possible to use in an uncontrolled way', async () => {
+      let handleSubmission = jest.fn()
+
+      render(
+        <form
+          onSubmit={(e) => {
+            e.preventDefault()
+            handleSubmission(Object.fromEntries(new FormData(e.target as HTMLFormElement)))
+          }}
+        >
+          <Listbox name="assignee">
+            <Listbox.Button>Trigger</Listbox.Button>
+            <Listbox.Options>
+              <Listbox.Option value="alice">Alice</Listbox.Option>
+              <Listbox.Option value="bob">Bob</Listbox.Option>
+              <Listbox.Option value="charlie">Charlie</Listbox.Option>
+            </Listbox.Options>
+          </Listbox>
+          <button id="submit">submit</button>
+        </form>
+      )
+
+      await click(document.getElementById('submit'))
+
+      // No values
+      expect(handleSubmission).toHaveBeenLastCalledWith({})
+
+      // Open listbox
+      await click(getListboxButton())
+
+      // Choose alice
+      await click(getListboxOptions()[0])
+
+      // Submit
+      await click(document.getElementById('submit'))
+
+      // Alice should be submitted
+      expect(handleSubmission).toHaveBeenLastCalledWith({ assignee: 'alice' })
+
+      // Open listbox
+      await click(getListboxButton())
+
+      // Choose charlie
+      await click(getListboxOptions()[2])
+
+      // Submit
+      await click(document.getElementById('submit'))
+
+      // Charlie should be submitted
+      expect(handleSubmission).toHaveBeenLastCalledWith({ assignee: 'charlie' })
+    })
+
+    it('should be possible to provide a default value', async () => {
+      let handleSubmission = jest.fn()
+
+      render(
+        <form
+          onSubmit={(e) => {
+            e.preventDefault()
+            handleSubmission(Object.fromEntries(new FormData(e.target as HTMLFormElement)))
+          }}
+        >
+          <Listbox name="assignee" defaultValue="bob">
+            <Listbox.Button>Trigger</Listbox.Button>
+            <Listbox.Options>
+              <Listbox.Option value="alice">Alice</Listbox.Option>
+              <Listbox.Option value="bob">Bob</Listbox.Option>
+              <Listbox.Option value="charlie">Charlie</Listbox.Option>
+            </Listbox.Options>
+          </Listbox>
+          <button id="submit">submit</button>
+        </form>
+      )
+
+      await click(document.getElementById('submit'))
+
+      // Bob is the defaultValue
+      expect(handleSubmission).toHaveBeenLastCalledWith({ assignee: 'bob' })
+
+      // Open listbox
+      await click(getListboxButton())
+
+      // Choose alice
+      await click(getListboxOptions()[0])
+
+      // Submit
+      await click(document.getElementById('submit'))
+
+      // Alice should be submitted
+      expect(handleSubmission).toHaveBeenLastCalledWith({ assignee: 'alice' })
+    })
+
+    it('should still call the onChange listeners when choosing new values', async () => {
+      let handleChange = jest.fn()
+
+      render(
+        <Listbox name="assignee" onChange={handleChange}>
+          <Listbox.Button>Trigger</Listbox.Button>
+          <Listbox.Options>
+            <Listbox.Option value="alice">Alice</Listbox.Option>
+            <Listbox.Option value="bob">Bob</Listbox.Option>
+            <Listbox.Option value="charlie">Charlie</Listbox.Option>
+          </Listbox.Options>
+        </Listbox>
+      )
+
+      // Open listbox
+      await click(getListboxButton())
+
+      // Choose alice
+      await click(getListboxOptions()[0])
+
+      // Open listbox
+      await click(getListboxButton())
+
+      // Choose bob
+      await click(getListboxOptions()[1])
+
+      // Change handler should have been called twice
+      expect(handleChange).toHaveBeenNthCalledWith(1, 'alice')
+      expect(handleChange).toHaveBeenNthCalledWith(2, 'bob')
+    })
+  })
 })
 
 describe('Rendering composition', () => {