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// Copyright (c) 2026 Cloudflare, Inc.
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// Licensed under the Apache 2.0 license found in the LICENSE file or at:
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//     https://opensource.org/licenses/Apache-2.0
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import { strictEqual } from 'node:assert';
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// https://github.com/cloudflare/workerd/issues/5934
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export const formDataUnionTypeOverloads = {
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  test() {
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    const formData = new FormData();
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    formData.append('stringKey', 'stringValue' as string | Blob);
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    strictEqual(formData.get('stringKey'), 'stringValue');
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    // We explicitly use string | Blob to test types.
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    const blob: string | Blob = new Blob(['blob content'], {
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      type: 'text/plain',
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    });
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    formData.append('blobKey', blob);
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    strictEqual(formData.get('blobKey') instanceof File, true);
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    const value: string | Blob = 'setValue';
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    formData.set('setStringKey', value);
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    strictEqual(formData.get('setStringKey'), 'setValue');
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    formData.set('setBlobKey', blob);
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    strictEqual(formData.get('setBlobKey') instanceof File, true);
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    const values: Array<{ key: string; value: string | Blob }> = [
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      { key: 'key1', value: 'string value' },
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      { key: 'key2', value: new Blob(['blob']) },
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    ];
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    const formData2 = new FormData();
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    for (const { key, value } of values) {
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      if (typeof value === 'string' || value instanceof Blob) {
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        formData2.append(key, value);
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      }
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    }
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    strictEqual(formData2.get('key1'), 'string value');
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    strictEqual(formData2.get('key2') instanceof File, true);
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  },
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};