Enhance discriminative union errors

colinhacks · Oct 4, 2024 · 9078140 · 9078140
1 parent 3032e24
commit 9078140
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Showing 5 changed files with 47 additions and 32 deletions.
diff --git a/src/ZodError.ts b/src/ZodError.ts
@@ -1,4 +1,4 @@
-import type { TypeOf, ZodType } from ".";
+import type { ParsePath, TypeOf, ZodType } from ".";
 import { Primitive } from "./helpers/typeAliases";
 import { util, ZodParsedType } from "./helpers/util";
 
@@ -37,7 +37,7 @@ export const ZodIssueCode = util.arrayToEnum([
 export type ZodIssueCode = keyof typeof ZodIssueCode;
 
 export type ZodIssueBase = {
-  path: (string | number)[];
+  path: ParsePath;
   message?: string;
 };
 
@@ -66,6 +66,7 @@ export interface ZodInvalidUnionIssue extends ZodIssueBase {
 export interface ZodInvalidUnionDiscriminatorIssue extends ZodIssueBase {
   code: typeof ZodIssueCode.invalid_union_discriminator;
   options: Primitive[];
+  received: string;
 }
 
 export interface ZodInvalidEnumValueIssue extends ZodIssueBase {
@@ -239,23 +240,27 @@ export class ZodError<T = any> extends Error {
           let i = 0;
           while (i < issue.path.length) {
             const el = issue.path[i];
+            const value =
+              typeof el === "object" && "discriminator" in el && "value" in el
+                ? el.value
+                : el;
             const terminal = i === issue.path.length - 1;
 
             if (!terminal) {
-              curr[el] = curr[el] || { _errors: [] };
-              // if (typeof el === "string") {
-              //   curr[el] = curr[el] || { _errors: [] };
-              // } else if (typeof el === "number") {
+              curr[value] = curr[value] || { _errors: [] };
+              // if (typeof value === "string") {
+              //   curr[value] = curr[value] || { _errors: [] };
+              // } valuese if (typeof value === "number") {
               //   const errorArray: any = [];
               //   errorArray._errors = [];
-              //   curr[el] = curr[el] || errorArray;
+              //   curr[value] = curr[value] || errorArray;
               // }
             } else {
-              curr[el] = curr[el] || { _errors: [] };
-              curr[el]._errors.push(mapper(issue));
+              curr[value] = curr[value] || { _errors: [] };
+              curr[value]._errors.push(mapper(issue));
             }
 
-            curr = curr[el];
+            curr = curr[value];
             i++;
           }
         }
@@ -305,8 +310,15 @@ export class ZodError<T = any> extends Error {
     const formErrors: U[] = [];
     for (const sub of this.issues) {
       if (sub.path.length > 0) {
-        fieldErrors[sub.path[0]] = fieldErrors[sub.path[0]] || [];
-        fieldErrors[sub.path[0]].push(mapper(sub));
+        const pathItem = sub.path[0];
+        const value =
+          typeof pathItem === "object" &&
+          "discriminator" in pathItem &&
+          "value" in pathItem
+            ? pathItem.value
+            : pathItem;
+        fieldErrors[value] = fieldErrors[value] || [];
+        fieldErrors[value].push(mapper(sub));
       } else {
         formErrors.push(mapper(sub));
       }
@@ -324,7 +336,7 @@ type stripPath<T extends object> = T extends any
   : never;
 
 export type IssueData = stripPath<ZodIssueOptionalMessage> & {
-  path?: (string | number)[];
+  path?: ParsePath;
   fatal?: boolean;
 };
 

diff --git a/src/__tests__/discriminated-unions.test.ts b/src/__tests__/discriminated-unions.test.ts
@@ -94,8 +94,10 @@ test("invalid discriminator value", () => {
       {
         code: z.ZodIssueCode.invalid_union_discriminator,
         options: ["a", "b"],
-        message: "Invalid discriminator value. Expected 'a' | 'b'",
+        message:
+          "Invalid discriminator value. Expected 'a' | 'b', received 'x'",
         path: ["type"],
+        received: "x",
       },
     ]);
   }
@@ -114,7 +116,7 @@ test("valid discriminator value, invalid data", () => {
         code: z.ZodIssueCode.invalid_type,
         expected: z.ZodParsedType.string,
         message: "Required",
-        path: ["a"],
+        path: [{ discriminator: "type", value: "a" }, "a"],
         received: z.ZodParsedType.undefined,
       },
     ]);
@@ -189,7 +191,7 @@ test("async - invalid", async () => {
         code: "invalid_type",
         expected: "string",
         received: "number",
-        path: ["a"],
+        path: [{ discriminator: "type", value: "a" }, "a"],
         message: "Expected string, received number",
       },
     ]);

diff --git a/src/helpers/parseUtil.ts b/src/helpers/parseUtil.ts
@@ -5,7 +5,7 @@ import type { ZodParsedType } from "./util";
 
 export const makeIssue = (params: {
   data: any;
-  path: (string | number)[];
+  path: ParsePath;
   errorMaps: ZodErrorMap[];
   issueData: IssueData;
 }): ZodIssue => {
@@ -41,12 +41,15 @@ export const makeIssue = (params: {
 };
 
 export type ParseParams = {
-  path: (string | number)[];
+  path: ParsePath;
   errorMap: ZodErrorMap;
   async: boolean;
 };
 
-export type ParsePathComponent = string | number;
+export type ParsePathComponent =
+  | string
+  | number
+  | { discriminator: string; value: string };
 export type ParsePath = ParsePathComponent[];
 export const EMPTY_PATH: ParsePath = [];
 
@@ -65,7 +68,7 @@ export interface ParseContext {
 
 export type ParseInput = {
   data: any;
-  path: (string | number)[];
+  path: ParsePath;
   parent: ParseContext;
 };
 

diff --git a/src/locales/en.ts b/src/locales/en.ts
@@ -29,7 +29,7 @@ const errorMap: ZodErrorMap = (issue, _ctx) => {
     case ZodIssueCode.invalid_union_discriminator:
       message = `Invalid discriminator value. Expected ${util.joinValues(
         issue.options
-      )}`;
+      )}, received '${issue.received}'`;
       break;
     case ZodIssueCode.invalid_enum_value:
       message = `Invalid enum value. Expected ${util.joinValues(

diff --git a/src/types.ts b/src/types.ts
@@ -43,7 +43,7 @@ import {
 
 export interface RefinementCtx {
   addIssue: (arg: IssueData) => void;
-  path: (string | number)[];
+  path: ParsePath;
 }
 export type ZodRawShape = { [k: string]: ZodTypeAny };
 export type ZodTypeAny = ZodType<any, any, any>;
@@ -3138,22 +3138,20 @@ export class ZodDiscriminatedUnion<
         code: ZodIssueCode.invalid_union_discriminator,
         options: Array.from(this.optionsMap.keys()),
         path: [discriminator],
+        received: discriminatorValue,
       });
       return INVALID;
     }
 
+    const optionCtx = {
+      data: ctx.data,
+      path: [...ctx.path, { discriminator, value: discriminatorValue }],
+      parent: ctx,
+    };
     if (ctx.common.async) {
-      return option._parseAsync({
-        data: ctx.data,
-        path: ctx.path,
-        parent: ctx,
-      }) as any;
+      return option._parseAsync(optionCtx) as any;
     } else {
-      return option._parseSync({
-        data: ctx.data,
-        path: ctx.path,
-        parent: ctx,
-      }) as any;
+      return option._parseSync(optionCtx) as any;
     }
   }