fix: expose array element validation errors in zod resolver (#119)

Co-authored-by: Young Min Kim <[email protected]>

Author: aprilrd

src/__snapshots__/zod.test.ts.snap

@@ -133,6 +133,23 @@ Object {
         "invalid_type": "Expected number, received string",
       },
     },
+    "likedUsers": Object {
+      "0": Object {
+        "id": Object {
+          "message": "Expected number, received string",
+          "type": "invalid_type",
+          "types": Object {
+            "invalid_type": "Expected number, received string",
+          },
+        },
+      },
+      "message": "Invalid input",
+      "type": "invalid_union",
+      "types": Object {
+        "invalid_type": "Expected undefined, received array",
+        "invalid_union": "Invalid input",
+      },
+    },
     "password": Object {
       "message": "Should be at least 8 characters",
       "type": "too_small",

src/zod.test.ts

@@ -10,6 +10,13 @@ const schema = z
     author: z.object({
       id: z.number(),
     }),
+    likedUsers: z
+      .array(
+        z.object({
+          id: z.number(),
+        }),
+      )
+      .optional(),
     count: z.number().positive().int(),
     date: z.date(),
     url: z.string().url(),
@@ -36,6 +43,7 @@ describe('zodResolver', () => {
       author: {
         id: 1,
       },
+      likedUsers: [{ id: 1 }],
       count: 4,
       date: new Date(),
       url: 'https://github.com/react-hook-form/resolvers',
@@ -73,6 +81,7 @@ describe('zodResolver', () => {
       author: {
         id: '1',
       },
+      likedUsers: [{ id: '1' }],
       count: -5,
       date: 'date',
       password: 'R',

src/zod.ts

@@ -17,39 +17,48 @@ const parseErrorSchema = (
     return {};
   }
 
-  return zodError.errors.reduce<Record<string, any>>(
-    (previous, { path, message, code: type }) => {
-      const currentPath = convertArrayToPathName(path);
+  const errors = [...zodError.errors];
+  let previous: Record<string, any> = {};
 
-      return {
-        ...previous,
-        ...(path
-          ? previous[currentPath] && validateAllFieldCriteria
-            ? {
-                [currentPath]: appendErrors(
-                  currentPath,
-                  validateAllFieldCriteria,
-                  previous,
-                  type,
-                  message,
-                ),
-              }
-            : {
-                [currentPath]: previous[currentPath] || {
-                  message,
-                  type,
-                  ...(validateAllFieldCriteria
-                    ? {
-                        types: { [type]: message || true },
-                      }
-                    : {}),
-                },
-              }
-          : {}),
-      };
-    },
-    {},
-  );
+  for (const error of errors) {
+    const { path, message, code: type } = error;
+    const currentPath = convertArrayToPathName(path);
+
+    if ('unionErrors' in error) {
+      for (const subErrors of error.unionErrors.map((e) => e.errors)) {
+        errors.push(...subErrors);
+      }
+    }
+
+    previous = {
+      ...previous,
+      ...(path
+        ? previous[currentPath] && validateAllFieldCriteria
+          ? {
+              [currentPath]: appendErrors(
+                currentPath,
+                validateAllFieldCriteria,
+                previous,
+                type,
+                message,
+              ),
+            }
+          : {
+              [currentPath]: previous[currentPath] || {
+                message,
+                type,
+                ...(validateAllFieldCriteria
+                  ? {
+                      types: { [type]: message || true },
+                    }
+                  : {}),
+              },
+            }
+        : {}),
+    };
+  }
+
+  return previous;
 };
 
 export const zodResolver = <T extends z.ZodSchema<any, any>>(