fix: Correctly handle array header values

packages/@pollyjs/adapter-node-http/tests/integration/persister-fs-node-fetch-test.js

@@ -0,0 +1,18 @@
+import '@pollyjs-tests/helpers/global-fetch';
+
+import setupPersister from '@pollyjs-tests/helpers/setup-persister';
+import setupFetchRecord from '@pollyjs-tests/helpers/setup-fetch-record';
+import persisterTests from '@pollyjs-tests/integration/persister-tests';
+import { setupMocha as setupPolly } from '@pollyjs/core';
+
+import pollyConfig from '../utils/polly-config';
+
+describe.only('Integration | FS Persister | node-fetch', function() {
+  setupPolly.beforeEach(pollyConfig);
+
+  setupFetchRecord({ host: 'http://localhost:4000' });
+  setupPersister();
+  setupPolly.afterEach();
+
+  persisterTests();
+});

packages/@pollyjs/adapter/src/index.js

@@ -3,6 +3,7 @@ import { ACTIONS, MODES, Serializers, assert } from '@pollyjs/utils';
 import Interceptor from './-private/interceptor';
 import isExpired from './utils/is-expired';
 import stringifyRequest from './utils/stringify-request';
+import normalizeRecordedResponse from './utils/normalize-recorded-response';
 
 const REQUEST_HANDLER = Symbol();
 
@@ -185,19 +186,11 @@ export default class Adapter {
       await this.timeout(pollyRequest, recordingEntry);
       pollyRequest.action = ACTIONS.REPLAY;
 
-      const { status, statusText, headers, content } = recordingEntry.response;
-      const normalizedResponse = {
-        statusText,
-        statusCode: status,
-        headers: (headers || []).reduce((accum, { name, value }) => {
-          accum[name] = value;
-
-          return accum;
-        }, {}),
-        body: content && content.text
-      };
-
-      return this.onReplay(pollyRequest, normalizedResponse, recordingEntry);
+      return this.onReplay(
+        pollyRequest,
+        normalizeRecordedResponse(recordingEntry.response),
+        recordingEntry
+      );
     }
 
     if (config.recordIfMissing) {

packages/@pollyjs/adapter/src/utils/normalize-recorded-response.js

@@ -0,0 +1,30 @@
+const { isArray } = Array;
+
+export default function normalizeRecordedResponse(response) {
+  const { status, statusText, headers, content } = response;
+
+  return {
+    statusText,
+    statusCode: status,
+    headers: normalizeHeaders(headers),
+    body: content && content.text
+  };
+}
+
+function normalizeHeaders(headers) {
+  return (headers || []).reduce((accum, { name, value }) => {
+    const existingValue = accum[name];
+
+    if (existingValue) {
+      if (!isArray(existingValue)) {
+        accum[name] = [existingValue];
+      }
+
+      accum[name].push(value);
+    } else {
+      accum[name] = value;
+    }
+
+    return accum;
+  }, {});
+}

packages/@pollyjs/persister/src/har/request.js

@@ -2,6 +2,7 @@ import getByteLength from 'utf8-byte-length';
 import setCookies from 'set-cookie-parser';
 
 import toNVPairs from './utils/to-nv-pairs';
+import getLastHeader from './utils/get-last-header';
 
 function headersSize(request) {
   const keys = [];
@@ -34,7 +35,7 @@ export default class Request {
 
     if (request.body) {
       this.postData = {
-        mimeType: request.getHeader('Content-Type') || 'text/plain',
+        mimeType: getLastHeader(this, 'Content-Type') || 'text/plain',
         params: []
       };
 
@@ -43,8 +44,10 @@ export default class Request {
       }
     }
 
-    if (request.hasHeader('Content-Length')) {
-      this.bodySize = parseInt(request.getHeader('Content-Length'), 10);
+    const contentLength = getLastHeader(this, 'Content-Length');
+
+    if (contentLength) {
+      this.bodySize = parseInt(contentLength, 10);
     } else {
       this.bodySize =
         this.postData && this.postData.text

packages/@pollyjs/persister/src/har/response.js

@@ -2,6 +2,7 @@ import getByteLength from 'utf8-byte-length';
 import setCookies from 'set-cookie-parser';
 
 import toNVPairs from './utils/to-nv-pairs';
+import getLastHeader from './utils/get-last-header';
 
 function headersSize(response) {
   const keys = [];
@@ -28,24 +29,26 @@ export default class Response {
     this.headers = toNVPairs(response.headers);
     this.headersSize = headersSize(this);
     this.cookies = setCookies.parse(response.getHeader('Set-Cookie'));
-    this.redirectURL = '';
+    this.redirectURL = getLastHeader(this, 'Location') || '';
 
     this.content = {
-      mimeType: response.getHeader('Content-Type') || 'text/plain'
+      mimeType: getLastHeader(this, 'Content-Type') || 'text/plain'
     };
 
     if (response.body && typeof response.body === 'string') {
       this.content.text = response.body;
     }
 
-    if (response.hasHeader('Content-Length')) {
-      this.content.size = parseInt(response.getHeader('Content-Length'), 10);
+    const contentLength = getLastHeader(this, 'Content-Length');
+
+    if (contentLength) {
+      this.content.size = parseInt(contentLength, 10);
     } else {
       this.content.size = this.content.text
         ? getByteLength(this.content.text)
         : 0;
     }
 
-    this.bodySize = this.content ? this.content.size : 0;
+    this.bodySize = this.content.size;
   }
 }

packages/@pollyjs/persister/src/har/utils/get-last-header.js

@@ -0,0 +1,9 @@
+export default function getLastHeader({ headers }, name) {
+  name = name.toLowerCase();
+
+  for (let i = headers.length - 1; i >= 0; i--) {
+    if (headers[i].name === name) {
+      return headers[i].value;
+    }
+  }
+}

packages/@pollyjs/persister/src/har/utils/to-nv-pairs.js

@@ -1,5 +1,16 @@
 const { keys } = Object;
+const { isArray } = Array;
 
 export default function toNVPairs(o) {
-  return keys(o || {}).map(name => ({ name, value: o[name] }));
+  return keys(o || {}).reduce((pairs, name) => {
+    const value = o[name];
+
+    if (isArray(value)) {
+      pairs.push(...value.map(v => ({ name, value: v })));
+    } else {
+      pairs.push({ name, value });
+    }
+
+    return pairs;
+  }, []);
 }