refactor: removes explicit normalization from "validateHeaders"

Author: artem-zakharchenko

lib/api/units/normalize/normalizeHeaders.js

@@ -13,16 +13,19 @@ const normalizeHeaders = (headers) => {
   }
 
   const headersType = typeof headers;
+  const isHeadersNull = headers == null;
 
-  if (headersType === null || headersType !== 'object') {
+  if (isHeadersNull || headersType !== 'object') {
     throw new Error(
-      `Can't validate: expected "headers" to be an Object, but got: ${headersType}.`
+      `Can't validate: expected "headers" to be an Object, but got: ${
+        isHeadersNull ? 'null' : headersType
+      }.`
     );
   }
 
   return Object.keys(headers).reduce(
-    (acc, name) => ({
-      ...acc,
+    (normalizedHeaders, name) => ({
+      ...normalizedHeaders,
       [name.toLowerCase()]:
         typeof headers[name] === 'string'
           ? normalizeStringValue(headers[name])

lib/api/units/validateHeaders.js

@@ -2,18 +2,6 @@ const { HeadersJsonExample } = require('../../validators/headers-json-example');
 
 const APIARY_JSON_HEADER_TYPE = 'application/vnd.apiary.http-headers+json';
 
-function normalizeHeaders(headers) {
-  return headers instanceof Object
-    ? Object.keys(headers).reduce(
-        (acc, headerName) =>
-          Object.assign({}, acc, {
-            [headerName.toLowerCase()]: headers[headerName]
-          }),
-        {}
-      )
-    : null;
-}
-
 function getHeadersType(headers) {
   return headers instanceof Object && !Array.isArray(headers)
     ? APIARY_JSON_HEADER_TYPE
@@ -26,18 +14,16 @@ function getHeadersType(headers) {
  * @param {Object} expected
  */
 function validateHeaders(real, expected) {
-  const realHeaders = normalizeHeaders(real.headers);
-  const expectedHeaders = normalizeHeaders(expected.headers);
-  const realType = getHeadersType(realHeaders);
-  const expectedType = getHeadersType(expectedHeaders);
+  const realType = getHeadersType(real.headers);
+  const expectedType = getHeadersType(expected.headers);
   const results = [];
 
   const hasJsonHeaders =
     realType === APIARY_JSON_HEADER_TYPE &&
     expectedType === APIARY_JSON_HEADER_TYPE;
 
   const validator = hasJsonHeaders
-    ? new HeadersJsonExample(realHeaders, expectedHeaders)
+    ? new HeadersJsonExample(real.headers, expected.headers)
     : null;
   const rawData = validator && validator.validate();