Fix getFieldset with interfaces and nullable schemas

packages/conform-dom/form.ts

@@ -55,10 +55,7 @@ export type DefaultValue<Schema> = Schema extends
 	: Schema extends Array<infer Item>
 	? Array<DefaultValue<Item>> | null | undefined
 	: Schema extends Record<string, any>
-	?
-			| { [Key in keyof Combine<Schema>]?: DefaultValue<Combine<Schema>[Key]> }
-			| null
-			| undefined
+	? { [Key in keyof Schema]?: DefaultValue<Schema[Key]> } | null | undefined
 	: string | null | undefined;
 
 export type FormValue<Schema> = Schema extends
@@ -77,9 +74,7 @@ export type FormValue<Schema> = Schema extends
 	: Schema extends Array<infer Item>
 	? string | Array<FormValue<Item>> | undefined
 	: Schema extends Record<string, any>
-	?
-			| { [Key in keyof Combine<Schema>]?: DefaultValue<Combine<Schema>[Key]> }
-			| undefined
+	? { [Key in keyof Schema]?: FormValue<Schema[Key]> } | null | undefined
 	: unknown;
 
 const error = Symbol('error');
@@ -258,8 +253,7 @@ function createFormMeta<Schema, FormError, FormValue>(
 ): FormMeta<FormError> {
 	const lastResult = !initialized ? options.lastResult : undefined;
 	const defaultValue = options.defaultValue
-		? // @ts-expect-error
-		  (serialize(options.defaultValue) as Record<string, unknown>)
+		? (serialize(options.defaultValue) as Record<string, unknown>)
 		: {};
 	const initialValue = lastResult?.initialValue ?? defaultValue;
 	const result: FormMeta<FormError> = {

packages/conform-react/context.tsx

@@ -82,16 +82,17 @@ type SubfieldMetadata<
 	Schema,
 	FormSchema extends Record<string, any>,
 	FormError,
-	CombinedSchema = Combine<Schema>,
-> = Exclude<Schema, undefined> extends Array<infer Item>
+> = [Schema] extends [Primitive]
+	? {}
+	: [Schema] extends [Array<infer Item> | null | undefined]
 	? {
 			getFieldList: () => Array<FieldMetadata<Item, FormSchema, FormError>>;
 	  }
-	: Exclude<Schema, undefined> extends Record<string, unknown>
+	: [Schema] extends [Record<string, any> | null | undefined]
 	? {
 			getFieldset: () => Required<{
-				[Key in keyof CombinedSchema]: FieldMetadata<
-					CombinedSchema[Key],
+				[Key in keyof Combine<Schema>]: FieldMetadata<
+					Combine<Schema>[Key],
 					FormSchema,
 					FormError
 				>;

playground/app/routes/typing.tsx

@@ -7,24 +7,28 @@ import {
 import { Form } from '@remix-run/react';
 import { Playground } from '~/components';
 
-type Task = { content: string; completed: boolean };
+interface Task {
+	content: string;
+	completed: boolean;
+}
 
-type Rule = {
+interface Rule {
 	type: 'rule';
 	key: string;
 	operator: string;
 	value: string;
-};
+}
 
-type Group = {
+interface Group {
 	type: 'group';
 	conditions: Array<Group | Rule>;
-};
+}
 
 type Schema =
 	| {
 			intent: 'foo';
 			tasks: Array<Task>;
+			date: Date;
 	  }
 	| {
 			intent: 'bar';
@@ -118,6 +122,15 @@ export default function Example() {
 	// @ts-expect-error
 	isFieldMetadataType1<Array<string>>(tasks);
 
+	const date = fields.date;
+
+	isFieldMetadataType0(date);
+	isFieldMetadataType1<Date>(date);
+	isFieldMetadataType1<Date | undefined>(date);
+
+	// @ts-expect-error
+	date.getFieldset();
+
 	const tasksList = tasks.getFieldList();
 
 	isFieldMetadataType0(tasksList[0]);