From 043539307f9873b36ff42bbe04c306cb59eed82f Mon Sep 17 00:00:00 2001
From: ragulka <illimar.tambek@gmail.com>
Date: Tue, 19 Nov 2024 16:24:21 +0200
Subject: [PATCH] Add defaultToFirstOption prop to Combobox

---
 .../src/components/combobox/combobox.test.ts  | 40 +++++++++++++++++++
 .../src/components/combobox/combobox.ts       |  6 ++-
 .../combobox/combobox-with-pure-tailwind.vue  |  9 +----
 3 files changed, 46 insertions(+), 9 deletions(-)

diff --git a/packages/@headlessui-vue/src/components/combobox/combobox.test.ts b/packages/@headlessui-vue/src/components/combobox/combobox.test.ts
index 433fddddad..651c6b9395 100644
--- a/packages/@headlessui-vue/src/components/combobox/combobox.test.ts
+++ b/packages/@headlessui-vue/src/components/combobox/combobox.test.ts
@@ -2708,6 +2708,46 @@ describe.each([{ virtual: true }, { virtual: false }])(
             assertNoActiveComboboxOption()
           })
         )
+
+        it(
+          'should be possible to go to the first item if no value is set and first option is not active by default',
+          suppressConsoleLogs(async () => {
+            renderTemplate({
+              template: html`
+                <Combobox v-model="value" :default-to-first-option="false" as="div">
+                  <ComboboxInput />
+                  <ComboboxButton>Trigger</ComboboxButton>
+                  <ComboboxOptions>
+                    <ComboboxOption value="a">Option A</ComboboxOption>
+                    <ComboboxOption value="b">Option B</ComboboxOption>
+                    <ComboboxOption value="c">Option C</ComboboxOption>
+                  </ComboboxOptions>
+                </Combobox>
+              `,
+              setup: () => ({ value: ref(null) }),
+            })
+
+            assertComboboxButton({
+              state: ComboboxState.InvisibleUnmounted,
+              attributes: { id: 'headlessui-combobox-button-2' },
+            })
+            assertComboboxList({ state: ComboboxState.InvisibleUnmounted })
+
+            // Open combobox
+            await click(getComboboxButton())
+
+            let options = getComboboxOptions()
+
+            // Verify that we have no active option
+            assertNoActiveComboboxOption()
+
+            // Go down once
+            await press(Keys.ArrowDown)
+
+            // We should be on the next item
+            assertActiveComboboxOption(options[0])
+          })
+        )
       })
 
       describe('`ArrowUp` key', () => {
diff --git a/packages/@headlessui-vue/src/components/combobox/combobox.ts b/packages/@headlessui-vue/src/components/combobox/combobox.ts
index 27b2a1c1d2..5b0f775aa1 100644
--- a/packages/@headlessui-vue/src/components/combobox/combobox.ts
+++ b/packages/@headlessui-vue/src/components/combobox/combobox.ts
@@ -252,6 +252,7 @@ export let Combobox = defineComponent({
       >,
       default: undefined,
     },
+    defaultToFirstOption: { type: [Boolean], default: false },
     form: { type: String, optional: true },
     name: { type: String, optional: true },
     nullable: { type: Boolean, default: false },
@@ -459,7 +460,7 @@ export let Combobox = defineComponent({
         activeOptionIndex.value = null
       },
       openCombobox() {
-        defaultToFirstOption.value = true
+        defaultToFirstOption.value = props.defaultToFirstOption
 
         if (props.disabled) return
         if (comboboxState.value === ComboboxStates.Open) return
@@ -526,7 +527,7 @@ export let Combobox = defineComponent({
           // It's possible that the activeOptionIndex is set to `null` internally, but
           // this means that we will fallback to the first non-disabled option by default.
           // We have to take this into account.
-          if (adjustedState.activeOptionIndex === null) {
+          if (adjustedState.activeOptionIndex === null && props.defaultToFirstOption) {
             let localActiveOptionIndex = adjustedState.options.findIndex(
               (option) => !option.dataRef.disabled
             )
@@ -743,6 +744,7 @@ export let Combobox = defineComponent({
             ...omit(theirProps, [
               'by',
               'defaultValue',
+              'defaultToFirstOption',
               'immediate',
               'modelValue',
               'multiple',
diff --git a/playgrounds/vue/src/components/combobox/combobox-with-pure-tailwind.vue b/playgrounds/vue/src/components/combobox/combobox-with-pure-tailwind.vue
index 3ffcd11fd9..c926547b88 100644
--- a/playgrounds/vue/src/components/combobox/combobox-with-pure-tailwind.vue
+++ b/playgrounds/vue/src/components/combobox/combobox-with-pure-tailwind.vue
@@ -33,7 +33,7 @@ export default defineComponent({
   },
   setup() {
     let query = ref('')
-    let activePerson = ref(everybody[2]) // everybody[Math.floor(Math.random() * everybody.length)]
+    let activePerson = ref(null)
     let filteredPeople = computed(() => {
       return query.value === ''
         ? everybody
@@ -42,11 +42,6 @@ export default defineComponent({
           })
     })
 
-    // Choose a random person on mount
-    onMounted(() => {
-      activePerson.value = everybody[Math.floor(Math.random() * everybody.length)]
-    })
-
     watch(activePerson, () => {
       query.value = ''
     })
@@ -67,7 +62,7 @@ export default defineComponent({
         Selected person: {{ activePerson?.name ?? 'Nobody yet' }}
       </div>
       <div class="space-y-1">
-        <Combobox v-model="activePerson" as="div">
+        <Combobox v-model="activePerson" as="div" nullable :default-to-first-option="false">
           <ComboboxLabel class="block text-sm font-medium leading-5 text-gray-700">
             Assigned to
           </ComboboxLabel>