refactor: simpler buildValidationErrors implementation, move `Valid…

…ationErrors` type to index

packages/next-safe-action/src/hooks.ts

@@ -115,7 +115,7 @@ const useActionCallbacks = <const S extends Schema, const Data>(
  * @param safeAction The typesafe action.
  * @param callbacks Optional callbacks executed based on the action status.
  *
- * {@link https://next-safe-action.dev/docs/usage-from-client/hooks/useaction See an example}
+ * {@link https://next-safe-action.dev/docs/usage/client-components/hooks/useaction See an example}
  */
 export const useAction = <const S extends Schema, const Data>(
 	safeAction: SafeAction<S, Data>,
@@ -174,7 +174,7 @@ export const useAction = <const S extends Schema, const Data>(
  * @param reducer Optimistic state reducer.
  * @param callbacks Optional callbacks executed based on the action status.
  *
- * {@link https://next-safe-action.dev/docs/usage-from-client/hooks/useoptimisticaction See an example}
+ * {@link https://next-safe-action.dev/docs/usage/client-components/hooks/useoptimisticaction See an example}
  */
 export const useOptimisticAction = <const S extends Schema, const Data>(
 	safeAction: SafeAction<S, Data>,

packages/next-safe-action/src/index.ts

@@ -2,7 +2,7 @@ import type { Infer, InferIn, Schema } from "@decs/typeschema";
 import { wrap } from "@decs/typeschema";
 import { isNotFoundError } from "next/dist/client/components/not-found.js";
 import { isRedirectError } from "next/dist/client/components/redirect.js";
-import type { MaybePromise, ValidationErrors } from "./utils";
+import type { ErrorList, Extend, MaybePromise, SchemaErrors } from "./utils";
 import { buildValidationErrors, isError } from "./utils";
 
 // TYPES
@@ -33,6 +33,11 @@ export type ServerCodeFn<S extends Schema, Data, Context> = (
 	ctx: Context
 ) => Promise<Data>;
 
+/**
+ * Type of the returned object when input validation fails.
+ */
+export type ValidationErrors<S extends Schema> = Extend<ErrorList & SchemaErrors<Infer<S>>>;
+
 // UTILS
 
 export const DEFAULT_SERVER_ERROR = "Something went wrong while executing the operation";

packages/next-safe-action/src/utils.ts

@@ -1,4 +1,5 @@
-import type { Infer, Schema, ValidationIssue } from "@decs/typeschema";
+import type { Schema, ValidationIssue } from "@decs/typeschema";
+import type { ValidationErrors } from ".";
 
 export const isError = (error: unknown): error is Error => error instanceof Error;
 
@@ -8,20 +9,18 @@ export const isError = (error: unknown): error is Error => error instanceof Erro
 export type MaybePromise<T> = Promise<T> | T;
 
 // Extends an object without printing "&".
-type Extend<S> = S extends infer U ? { [K in keyof U]: U[K] } : never;
+export type Extend<S> = S extends infer U ? { [K in keyof U]: U[K] } : never;
 
 // VALIDATION ERRORS
 
-type ErrorList = { _errors?: string[] } & {};
+// Object with an optional list of validation errors.
+export type ErrorList = { _errors?: string[] } & {};
 
-// Creates nested schema errors type using recursion.
-type SchemaErrors<S> = {
+// Creates nested schema validation errors type using recursion.
+export type SchemaErrors<S> = {
 	[K in keyof S]?: S[K] extends object ? Extend<ErrorList & SchemaErrors<S[K]>> : ErrorList;
 } & {};
 
-// Merges root errors with nested schema errors.
-export type ValidationErrors<S extends Schema> = Extend<ErrorList & SchemaErrors<Infer<S>>>;
-
 // This function is used to build the validation errors object from a list of validation issues.
 export const buildValidationErrors = <const S extends Schema>(issues: ValidationIssue[]) => {
 	const ve: any = {};
@@ -31,7 +30,7 @@ export const buildValidationErrors = <const S extends Schema>(issues: Validation
 
 		// When path is undefined or empty, set root errors.
 		if (!path || path.length === 0) {
-			ve._errors = Array.isArray(ve._errors) ? [...ve._errors, message] : [message];
+			ve._errors = ve._errors ? [...ve._errors, message] : [message];
 			continue;
 		}
 
@@ -42,7 +41,7 @@ export const buildValidationErrors = <const S extends Schema>(issues: Validation
 		for (let i = 0; i < path.length - 1; i++) {
 			const k = path[i]!;
 
-			if (!(k in ref)) {
+			if (!ref[k]) {
 				ref[k] = {};
 			}
 
@@ -54,8 +53,8 @@ export const buildValidationErrors = <const S extends Schema>(issues: Validation
 
 		// Set error for the current path. If `_errors` array exists, add the message to it.
 		ref[key] = (
-			Array.isArray(ref[key]?._errors)
-				? { ...structuredClone(ref[key]), _errors: [...ref[key]!._errors!, message] }
+			ref[key]?._errors
+				? { ...structuredClone(ref[key]), _errors: [...ref[key]._errors, message] }
 				: { ...structuredClone(ref[key]), _errors: [message] }
 		) satisfies ErrorList;
 	}