chore: create a type to remove the fields with a certain type

nestjs · Mar 18, 2023 · 936e0dc · 936e0dc
1 parent 62bf680
commit 936e0dc
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Showing 3 changed files with 12 additions and 4 deletions.
diff --git a/lib/omit-type.helper.ts b/lib/omit-type.helper.ts
@@ -9,7 +9,7 @@ import {
 export function OmitType<T, K extends keyof T>(
   classRef: Type<T>,
   keys: readonly K[],
-): MappedType<Omit<T, typeof keys[number]>> {
+): MappedType<Omit<T, (typeof keys)[number]>> {
   const isInheritedPredicate = (propertyKey: string) =>
     !keys.includes(propertyKey as K);
 
@@ -22,5 +22,5 @@ export function OmitType<T, K extends keyof T>(
   inheritValidationMetadata(classRef, OmitClassType, isInheritedPredicate);
   inheritTransformationMetadata(classRef, OmitClassType, isInheritedPredicate);
 
-  return OmitClassType as MappedType<Omit<T, typeof keys[number]>>;
+  return OmitClassType as MappedType<Omit<T, (typeof keys)[number]>>;
 }
diff --git a/lib/pick-type.helper.ts b/lib/pick-type.helper.ts
@@ -9,7 +9,7 @@ import {
 export function PickType<T, K extends keyof T>(
   classRef: Type<T>,
   keys: readonly K[],
-): MappedType<Pick<T, typeof keys[number]>> {
+): MappedType<Pick<T, (typeof keys)[number]>> {
   const isInheritedPredicate = (propertyKey: string) =>
     keys.includes(propertyKey as K);
 
@@ -21,5 +21,5 @@ export function PickType<T, K extends keyof T>(
   inheritValidationMetadata(classRef, PickClassType, isInheritedPredicate);
   inheritTransformationMetadata(classRef, PickClassType, isInheritedPredicate);
 
-  return PickClassType as MappedType<Pick<T, typeof keys[number]>>;
+  return PickClassType as MappedType<Pick<T, (typeof keys)[number]>>;
 }
diff --git a/lib/types/remove-fields-with-type.type.ts b/lib/types/remove-fields-with-type.type.ts
@@ -0,0 +1,8 @@
+// With this util we could remove the keys with never type from the original type.
+type KeysWithoutType<T, Type> = {
+  [K in keyof T]: T[K] extends Type ? never : K;
+}[keyof T];
+
+export type RemoveFieldsWithType<T, Type> = {
+  [K in KeysWithoutType<T, Type>]: T[K];
+};