test(core): added tests for headers file

test/core/headers.spec.ts

@@ -0,0 +1,127 @@
+import { BothValueHeaders } from '../../src/v2/@types';
+import {
+  getFlattenedHeadersMap,
+  getMultiValueHeadersMap,
+} from '../../src/v2/core';
+
+describe('getFlattenedHeadersMap', () => {
+  it('should return headers flattened', () => {
+    const headerLists: BothValueHeaders[] = [
+      {
+        'Accept-Encoding': 'gzip',
+        'Accept-Language': 'en-US,en;q=0.9',
+        Host: undefined,
+        'Content-Type': '',
+      },
+      {
+        'Accept-Encoding': ['gzip'],
+        'Accept-Language': ['en-US', 'en;q=0.9'],
+        Host: undefined,
+        'Content-Type': '',
+      },
+    ];
+
+    for (const headers of headerLists) {
+      const flattenedHeaders = getFlattenedHeadersMap(headers);
+
+      expect(Object.keys(flattenedHeaders).length).toEqual(
+        Object.keys(headers).length,
+      );
+
+      expect(flattenedHeaders).toHaveProperty('Accept-Encoding');
+      expect(flattenedHeaders['Accept-Encoding']).toEqual('gzip');
+      expect(flattenedHeaders['Accept-Language']).toEqual('en-US,en;q=0.9');
+    }
+  });
+
+  it('should return headers flattened with custom options', () => {
+    const defaultSingleValueHeaders = {
+      'Accept-Encoding': 'gzip',
+      'Accept-Language': 'en-US,en;q=0.9',
+    };
+    const defaultMultiValueHeaders = {
+      'Accept-Encoding': ['gzip'],
+      'Accept-Language': ['en-US', 'en;q=0.9'],
+    };
+
+    const headerLists: [
+      headers: BothValueHeaders,
+      separator: string,
+      lowerCase: boolean,
+    ][] = [
+      [defaultSingleValueHeaders, ',', false],
+      [defaultMultiValueHeaders, ',', false],
+      [defaultSingleValueHeaders, '|', false],
+      [defaultMultiValueHeaders, '|', false],
+      [defaultSingleValueHeaders, ',', true],
+      [defaultMultiValueHeaders, ',', true],
+      [defaultSingleValueHeaders, '|', true],
+      [defaultMultiValueHeaders, '|', true],
+    ];
+
+    for (const [headers, separator, lowerCase] of headerLists) {
+      const flattenedHeaders = getFlattenedHeadersMap(
+        headers,
+        separator,
+        lowerCase,
+      );
+
+      expect(Object.keys(flattenedHeaders).length).toEqual(
+        Object.keys(headers).length,
+      );
+
+      const checkedHeader = lowerCase ? 'accept-encoding' : 'Accept-Encoding';
+
+      const arrayCheckedHeader = lowerCase
+        ? 'accept-language'
+        : 'Accept-Language';
+
+      expect(flattenedHeaders).toHaveProperty(checkedHeader);
+      expect(flattenedHeaders[checkedHeader]).toEqual('gzip');
+
+      if (Array.isArray(headers['Accept-Language'])) {
+        expect(headers['Accept-Language']).toStrictEqual(
+          flattenedHeaders[arrayCheckedHeader].split(separator),
+        );
+      } else {
+        expect(headers['Accept-Language']).toStrictEqual(
+          flattenedHeaders[arrayCheckedHeader],
+        );
+      }
+    }
+  });
+});
+
+describe('getMultiValueHeadersMap', () => {
+  it('should return headers flattened', () => {
+    const headerLists: BothValueHeaders[] = [
+      {
+        'Accept-Encoding': 'gzip',
+        'Accept-Language': 'en-US,en;q=0.9',
+        Host: undefined,
+        'Content-Type': '',
+      },
+      {
+        'Accept-Encoding': ['gzip'],
+        'Accept-Language': ['en-US', 'en;q=0.9'],
+        Host: undefined,
+        'Content-Type': '',
+      },
+    ];
+
+    for (const headers of headerLists) {
+      const multiValueHeadersMap = getMultiValueHeadersMap(headers);
+
+      expect(Object.keys(multiValueHeadersMap).length).toEqual(
+        Object.keys(headers).length,
+      );
+
+      expect(multiValueHeadersMap).toHaveProperty('accept-encoding', ['gzip']);
+      expect(
+        Object.keys(multiValueHeadersMap).every(key =>
+          Array.isArray(multiValueHeadersMap[key]),
+        ),
+      );
+    }
+  });
+});