From 86a3404ab46cc5121591ff1055a945dac95c679c Mon Sep 17 00:00:00 2001
From: Han Feng <hi@fenghan.link>
Date: Mon, 28 Nov 2022 19:09:01 +0800
Subject: [PATCH] [Autocomplete] Fix inferred value type when `multiple` prop
 is `true` (#35275)

---
 .../AutocompleteUnstyled/useAutocomplete.d.ts  | 12 +++++-------
 .../src/Autocomplete/Autocomplete.spec.tsx     | 18 ++++++++++++++++++
 2 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/packages/mui-base/src/AutocompleteUnstyled/useAutocomplete.d.ts b/packages/mui-base/src/AutocompleteUnstyled/useAutocomplete.d.ts
index 57cc393c3710a6..de04268a6b826c 100644
--- a/packages/mui-base/src/AutocompleteUnstyled/useAutocomplete.d.ts
+++ b/packages/mui-base/src/AutocompleteUnstyled/useAutocomplete.d.ts
@@ -27,13 +27,11 @@ export function createFilterOptions<T>(
 
 export type AutocompleteFreeSoloValueMapping<FreeSolo> = FreeSolo extends true ? string : never;
 
-export type AutocompleteValue<T, Multiple, DisableClearable, FreeSolo> = Multiple extends
-  | undefined
-  | false
-  ? DisableClearable extends true
-    ? NonNullable<T | AutocompleteFreeSoloValueMapping<FreeSolo>>
-    : T | null | AutocompleteFreeSoloValueMapping<FreeSolo>
-  : Array<T | AutocompleteFreeSoloValueMapping<FreeSolo>>;
+export type AutocompleteValue<T, Multiple, DisableClearable, FreeSolo> = Multiple extends true
+  ? Array<T | AutocompleteFreeSoloValueMapping<FreeSolo>>
+  : DisableClearable extends true
+  ? NonNullable<T | AutocompleteFreeSoloValueMapping<FreeSolo>>
+  : T | null | AutocompleteFreeSoloValueMapping<FreeSolo>;
 
 export interface UseAutocompleteProps<
   T,
diff --git a/packages/mui-material/src/Autocomplete/Autocomplete.spec.tsx b/packages/mui-material/src/Autocomplete/Autocomplete.spec.tsx
index d2f6ab028c9040..fbd7edc2c79a20 100644
--- a/packages/mui-material/src/Autocomplete/Autocomplete.spec.tsx
+++ b/packages/mui-material/src/Autocomplete/Autocomplete.spec.tsx
@@ -66,6 +66,24 @@ function MyAutocomplete<
   renderInput={(params) => <TextField {...params} value={params.inputProps.value} />}
 />;
 
+interface Option {
+  label: string;
+  value: string;
+}
+const options: Option[] = [
+  { label: '1', value: '1' },
+  { label: '2', value: '2' },
+];
+const defaultOptions = [options[0], options[1]];
+<MyAutocomplete
+  multiple
+  options={options}
+  defaultValue={defaultOptions}
+  isOptionEqualToValue={(o, v) => o.label === v.label}
+  getOptionLabel={(o) => o.label}
+  renderInput={() => null}
+/>;
+
 interface Tag {
   color: string;
   label: string;