Add unit tests for baseFetch helpers

Author: wKovacs64

src/api/__tests__/base-fetch.test.ts

@@ -0,0 +1,98 @@
+import { describe, it, expect } from 'vitest';
+import { buildUrl, buildHeaders } from '../base-fetch.js';
+
+describe('internal: buildUrl', () => {
+  describe('base URL normalization', () => {
+    it('strips trailing slash from base URL', () => {
+      expect(buildUrl('https://example.com/', '/endpoint')).toBe('https://example.com/endpoint');
+    });
+
+    it('handles base URL without trailing slash', () => {
+      expect(buildUrl('https://example.com', '/endpoint')).toBe('https://example.com/endpoint');
+    });
+  });
+
+  describe('endpoint normalization', () => {
+    it('handles endpoint with leading slash', () => {
+      expect(buildUrl('https://example.com', '/endpoint')).toBe('https://example.com/endpoint');
+    });
+
+    it('adds leading slash to endpoint when missing', () => {
+      expect(buildUrl('https://example.com', 'endpoint')).toBe('https://example.com/endpoint');
+    });
+  });
+
+  describe('query params', () => {
+    it('appends query params to URL', () => {
+      expect(buildUrl('https://example.com', '/endpoint', { foo: 'bar' })).toBe(
+        'https://example.com/endpoint?foo=bar',
+      );
+    });
+
+    it('appends multiple query params', () => {
+      expect(buildUrl('https://example.com', '/endpoint', { foo: 'bar', baz: 'qux' })).toBe(
+        'https://example.com/endpoint?foo=bar&baz=qux',
+      );
+    });
+
+    it('encodes query param values', () => {
+      expect(buildUrl('https://example.com', '/endpoint', { foo: 'bar baz' })).toBe(
+        'https://example.com/endpoint?foo=bar+baz',
+      );
+    });
+
+    it('returns URL without query string when queryParams is undefined', () => {
+      expect(buildUrl('https://example.com', '/endpoint')).toBe('https://example.com/endpoint');
+    });
+
+    it('returns URL without query string when queryParams is empty', () => {
+      expect(buildUrl('https://example.com', '/endpoint', {})).toBe('https://example.com/endpoint');
+    });
+  });
+});
+
+describe('internal: buildHeaders', () => {
+  describe('extra headers', () => {
+    it('returns extra headers when provided', () => {
+      expect(buildHeaders(undefined, { 'X-Custom': 'value' })).toEqual({ 'X-Custom': 'value' });
+    });
+
+    it('returns empty object when no args provided', () => {
+      expect(buildHeaders()).toEqual({});
+    });
+  });
+
+  describe('User-Agent', () => {
+    it('uses custom userAgent when provided', () => {
+      const result = buildHeaders('custom-agent');
+      expect(result['User-Agent']).toBe('custom-agent');
+    });
+
+    it('merges custom userAgent with extra headers', () => {
+      const result = buildHeaders('custom-agent', { 'X-Custom': 'value' });
+      expect(result).toEqual({ 'User-Agent': 'custom-agent', 'X-Custom': 'value' });
+    });
+
+    it('uses default User-Agent when outside browser (no navigator)', () => {
+      const originalNavigator = global.navigator;
+      // @ts-expect-error: faking a non-browser (Node) environment
+      delete global.navigator;
+
+      const result = buildHeaders();
+      expect(result['User-Agent']).toMatch(/^hibp \d+\.\d+\.\d+/);
+
+      global.navigator = originalNavigator;
+    });
+
+    it('does not set User-Agent when inside browser (navigator exists)', () => {
+      const originalNavigator = global.navigator;
+      // eslint-disable-next-line @typescript-eslint/consistent-type-assertions
+      global.navigator = {} as Navigator;
+
+      const result = buildHeaders();
+      expect(result['User-Agent']).toBeUndefined();
+
+      global.navigator = originalNavigator;
+    });
+  });
+});

src/api/base-fetch.ts

@@ -26,7 +26,11 @@ export async function baseFetch({
   return fetch(url, requestInit);
 }
 
-function buildUrl(baseUrl: string, endpoint: string, queryParams?: Record<string, string>): string {
+export function buildUrl(
+  baseUrl: string,
+  endpoint: string,
+  queryParams?: Record<string, string>,
+): string {
   const base = baseUrl.replace(/\/$/g, '');
   const normalizedEndpoint = endpoint.startsWith('/') ? endpoint : `/${endpoint}`;
   const url = new URL(`${base}${normalizedEndpoint}`);
@@ -40,7 +44,10 @@ function buildUrl(baseUrl: string, endpoint: string, queryParams?: Record<string
   return url.toString();
 }
 
-function buildHeaders(userAgent?: string, extra?: Record<string, string>): Record<string, string> {
+export function buildHeaders(
+  userAgent?: string,
+  extra?: Record<string, string>,
+): Record<string, string> {
   const headers: Record<string, string> = { ...extra };
 
   if (userAgent) {