fix: [#1693] Tuple with empty items (#1712)

* Add testcase - tuple as sparse array

* Destructure array to make .map() work properly - ZodTuple

* Make tuple as sparse array test more clear

* Add testcase - array as sparse array

* Destructure array to make .map() work properly - ZodArray

deno/lib/__tests__/array.test.ts

@@ -64,3 +64,9 @@ test("continue parsing despite array size error", () => {
     expect(result.error.issues.length).toEqual(2);
   }
 });
+
+test("parse should fail given sparse array", () => {
+  const schema = z.array(z.string()).nonempty().min(1).max(3);
+
+  expect(() => schema.parse(new Array(3))).toThrow();
+});

deno/lib/__tests__/tuple.test.ts

@@ -89,6 +89,10 @@ test("tuple with rest schema", () => {
   util.assertEqual<t1, [string, number, ...boolean[]]>(true);
 });
 
+test("parse should fail given sparse array as tuple", () => {
+  expect(() => testTuple.parse(new Array(3))).toThrow();
+});
+
 // test('tuple with optional elements', () => {
 //   const result = z
 //     .tuple([z.string(), z.number().optional()])

deno/lib/types.ts

@@ -2851,7 +2851,7 @@ export class ZodTuple<
       status.dirty();
     }
 
-    const items = (ctx.data as any[])
+    const items = ([...ctx.data] as any[])
       .map((item, itemIndex) => {
         const schema = this._def.items[itemIndex] || this._def.rest;
         if (!schema) return null as any as SyncParseReturnType<any>;

src/__tests__/array.test.ts

@@ -63,3 +63,9 @@ test("continue parsing despite array size error", () => {
     expect(result.error.issues.length).toEqual(2);
   }
 });
+
+test("parse should fail given sparse array", () => {
+  const schema = z.array(z.string()).nonempty().min(1).max(3);
+
+  expect(() => schema.parse(new Array(3))).toThrow();
+});

src/__tests__/tuple.test.ts

@@ -88,6 +88,10 @@ test("tuple with rest schema", () => {
   util.assertEqual<t1, [string, number, ...boolean[]]>(true);
 });
 
+test("parse should fail given sparse array as tuple", () => {
+  expect(() => testTuple.parse(new Array(3))).toThrow();
+});
+
 // test('tuple with optional elements', () => {
 //   const result = z
 //     .tuple([z.string(), z.number().optional()])

src/types.ts

@@ -1713,7 +1713,7 @@ export class ZodArray<
 
     if (ctx.common.async) {
       return Promise.all(
-        (ctx.data as any[]).map((item, i) => {
+        ([...ctx.data] as any[]).map((item, i) => {
           return def.type._parseAsync(
             new ParseInputLazyPath(ctx, item, ctx.path, i)
           );
@@ -1723,7 +1723,7 @@ export class ZodArray<
       });
     }
 
-    const result = (ctx.data as any[]).map((item, i) => {
+    const result = ([...ctx.data] as any[]).map((item, i) => {
       return def.type._parseSync(
         new ParseInputLazyPath(ctx, item, ctx.path, i)
       );
@@ -2851,7 +2851,7 @@ export class ZodTuple<
       status.dirty();
     }
 
-    const items = (ctx.data as any[])
+    const items = ([...ctx.data] as any[])
       .map((item, itemIndex) => {
         const schema = this._def.items[itemIndex] || this._def.rest;
         if (!schema) return null as any as SyncParseReturnType<any>;