feat: add @robonen/fetch package - lightweight fetch wrapper with V8 optimizations

Co-authored-by: robonen <26167508+robonen@users.noreply.github.com>

core/fetch/src/error.test.ts

@@ -0,0 +1,71 @@
+import { describe, expect, it } from 'vitest';
+import { FetchError, createFetchError } from './error';
+import type { FetchContext } from './types';
+
+function makeContext(overrides: Partial<FetchContext> = {}): FetchContext {
+  return {
+    request: 'https://example.com/api',
+    options: { headers: new Headers() },
+    response: undefined,
+    error: undefined,
+    ...overrides,
+  } as FetchContext;
+}
+
+describe('FetchError', () => {
+  it('is an instance of Error', () => {
+    const err = new FetchError('oops');
+    expect(err).toBeInstanceOf(Error);
+    expect(err).toBeInstanceOf(FetchError);
+  });
+
+  it('has name "FetchError"', () => {
+    expect(new FetchError('x').name).toBe('FetchError');
+  });
+
+  it('preserves the message', () => {
+    expect(new FetchError('something went wrong').message).toBe('something went wrong');
+  });
+});
+
+describe('createFetchError', () => {
+  it('includes the request URL in the message', () => {
+    const err = createFetchError(makeContext());
+    expect(err.message).toContain('https://example.com/api');
+  });
+
+  it('appends status information when a response is present', () => {
+    const response = new Response('', { status: 404, statusText: 'Not Found' });
+    const err = createFetchError(makeContext({ response: response as never }));
+    expect(err.message).toContain('404');
+    expect(err.message).toContain('Not Found');
+    expect(err.status).toBe(404);
+    expect(err.statusCode).toBe(404);
+    expect(err.statusText).toBe('Not Found');
+    expect(err.statusMessage).toBe('Not Found');
+  });
+
+  it('appends the underlying error message when present', () => {
+    const networkErr = new Error('Failed to fetch');
+    const err = createFetchError(makeContext({ error: networkErr }));
+    expect(err.message).toContain('Failed to fetch');
+  });
+
+  it('populates response._data as data', () => {
+    const response = Object.assign(new Response('', { status: 422 }), { _data: { code: 42 } });
+    const err = createFetchError(makeContext({ response: response as never }));
+    expect(err.data).toEqual({ code: 42 });
+  });
+
+  it('works with a URL object as request', () => {
+    const ctx = makeContext({ request: new URL('https://example.com/test') });
+    const err = createFetchError(ctx);
+    expect(err.message).toContain('https://example.com/test');
+  });
+
+  it('works with a Request object as request', () => {
+    const ctx = makeContext({ request: new Request('https://example.com/req') });
+    const err = createFetchError(ctx);
+    expect(err.message).toContain('https://example.com/req');
+  });
+});