fix(types): undefined defaults produce optional outputs

jquense · Aug 23, 2022 · 1afbac0 · 1afbac0
1 parent f250109
commit 1afbac0
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Showing 3 changed files with 22 additions and 4 deletions.
diff --git a/src/schema.ts b/src/schema.ts
@@ -138,7 +138,7 @@ export default abstract class Schema<
 {
   readonly type: string;
 
-  declare readonly __outputType: ResolveFlags<TType, TFlags>;
+  declare readonly __outputType: ResolveFlags<TType, TFlags, TDefault>;
   declare readonly __context: TContext;
   declare readonly __flags: TFlags;
   declare readonly __isYupSchema__: boolean;

diff --git a/src/util/types.ts b/src/util/types.ts
@@ -1,3 +1,5 @@
+export type IfAny<T, Y, N> = 0 extends 1 & T ? Y : N;
+
 export type Maybe<T> = T | null | undefined;
 
 export type Preserve<T, U> = T extends U ? U : never;
@@ -35,8 +37,13 @@ export type ToggleDefault<F extends Flags, D> = Preserve<
   ? SetFlag<F, 'd'>
   : UnsetFlag<F, 'd'>;
 
-export type ResolveFlags<T, F extends Flags> = Preserve<F, 's'> extends never
+export type ResolveFlags<T, F extends Flags, D = T> = Preserve<
+  F,
+  's'
+> extends never
   ? Extract<F, 'd'> extends never
+    ? T
+    : D extends undefined
     ? T
     : Defined<T>
   : never;

diff --git a/test/types/types.ts b/test/types/types.ts
@@ -850,6 +850,17 @@ Object: {
 
     // $ExpectType null
     obj1.concat(obj2.default(null)).getDefault();
+
+    const optionalNonDefaultedObj = object({
+      nested: object({
+        h: number().required(),
+      })
+        .default(undefined)
+        .optional(),
+    });
+
+    // $ExpectType { h: number; } | undefined
+    optionalNonDefaultedObj.cast({}).nested;
   }
 
   SchemaOfDate: {
@@ -959,13 +970,13 @@ Object: {
 }
 
 Conditions: {
-  // $ExpectType StringSchema<string, AnyObject, undefined, ""> | NumberSchema<number | undefined, AnyObject, undefined, "">
+  // $ExpectType NumberSchema<number | undefined, AnyObject, undefined, ""> | StringSchema<string, AnyObject, undefined, "">
   string().when('foo', ([foo], schema) => (foo ? schema.required() : number()));
 
   // $ExpectType StringSchema<string | undefined, AnyObject, undefined, "">
   string().when('foo', ([foo], schema) => (foo ? schema.required() : schema));
 
-  // $ExpectType StringSchema<string, AnyObject, undefined, ""> | NumberSchema<number | undefined, AnyObject, undefined, "">
+  // $ExpectType NumberSchema<number | undefined, AnyObject, undefined, ""> | StringSchema<string, AnyObject, undefined, "">
   string().when('foo', {
     is: true,
     then: () => number(),