test: Test reply header arrays, args to header functions, and minor u…

…pdates (#1541)

Related discussion at #1542.

tests/test_reply_headers.js

@@ -3,6 +3,7 @@
 // Tests for header objects passed to `.reply()`, including header objects
 // containing lambdas.
 
+const { IncomingMessage } = require('http')
 const { test } = require('tap')
 const mikealRequest = require('request')
 const lolex = require('lolex')
@@ -11,68 +12,119 @@ const got = require('./got_client')
 
 require('./cleanup_after_each')()
 
-test('headers work', async t => {
-  const scope = nock('http://example.com')
+test('reply header is sent in the mock response', async t => {
+  const scope = nock('http://example.test')
     .get('/')
     .reply(200, 'Hello World!', { 'X-My-Headers': 'My Header value' })
 
-  const { headers } = await got('http://example.com/')
+  const { headers } = await got('http://example.test/')
 
   t.equivalent(headers, { 'x-my-headers': 'My Header value' })
   scope.done()
 })
 
-test('reply headers as function work', async t => {
-  const scope = nock('http://example.com')
+test('content-length header is sent with response', async t => {
+  const scope = nock('http://example.test')
+    .replyContentLength()
+    .get('/')
+    .reply(200, { hello: 'world' })
+
+  const { headers } = await got('http://example.test/')
+
+  t.equal(headers['content-length'], 17)
+  scope.done()
+})
+
+test('header array sends multiple reply headers', async t => {
+  const scope = nock('http://example.test')
+    .get('/')
+    .reply(200, 'Hello World!', {
+      'Set-Cookie': ['cookie1=foo', 'cookie2=bar'],
+    })
+
+  const { headers, rawHeaders } = await got('http://example.test/')
+  t.equivalent(headers, {
+    'set-cookie': ['cookie1=foo', 'cookie2=bar'],
+  })
+  t.equivalent(rawHeaders, ['Set-Cookie', ['cookie1=foo', 'cookie2=bar']])
+
+  scope.done()
+})
+
+test('reply header function is evaluated and the result sent in the mock response', async t => {
+  const scope = nock('http://example.test')
     .get('/')
     .reply(200, 'boo!', {
-      'X-My-Headers': (req, res, body) => body.toString(),
+      'X-My-Headers': () => 'yo!',
+    })
+
+  const { headers, rawHeaders } = await got('http://example.test/')
+
+  t.equivalent(headers, { 'x-my-headers': 'yo!' })
+  t.equivalent(rawHeaders, ['X-My-Headers', 'yo!'])
+  scope.done()
+})
+
+test('reply header function receives the correct arguments', async t => {
+  t.plan(4)
+
+  const { ClientRequest: OverriddenClientRequest } = require('http')
+  const scope = nock('http://example.test')
+    .post('/')
+    .reply(200, 'boo!', {
+      'X-My-Headers': (req, res, body) => {
+        t.type(req, OverriddenClientRequest)
+        t.type(res, IncomingMessage)
+        // TODO The current behavior is to pass the response body as a buffer.
+        // This doesn't seem at all helpful and seems like it is probably a
+        // bug.
+        // https://github.com/nock/nock/issues/1542
+        t.type(body, Buffer)
+        t.true(Buffer.from('boo!').equals(body))
+        return 'gotcha'
+      },
     })
 
-  const { headers, rawHeaders } = await got('http://example.com/')
+  await got.post('http://example.test/')
 
-  t.equivalent(headers, { 'x-my-headers': 'boo!' })
-  t.equivalent(rawHeaders, ['X-My-Headers', 'boo!'])
   scope.done()
 })
 
-test('reply headers as function are evaluated only once per request', async t => {
+test('reply headers function is evaluated exactly once', async t => {
   let counter = 0
-  const scope = nock('http://example.com')
+  const scope = nock('http://example.test')
     .get('/')
     .reply(200, 'boo!', {
-      'X-My-Headers': (req, res, body) => {
+      'X-My-Headers': () => {
         ++counter
-        return body.toString()
+        return 'heya'
       },
     })
 
-  const { headers, rawHeaders } = await got('http://example.com/')
+  await got('http://example.test/')
 
-  t.equivalent(headers, { 'x-my-headers': 'boo!' })
-  t.equivalent(rawHeaders, ['X-My-Headers', 'boo!'])
   scope.done()
 
   t.equal(counter, 1)
 })
 
-test('reply headers as function are evaluated on each request', async t => {
+test('reply header function are re-evaluated for every matching request', async t => {
   let counter = 0
-  const scope = nock('http://example.com')
+  const scope = nock('http://example.test')
     .get('/')
     .times(2)
     .reply(200, 'boo!', {
-      'X-My-Headers': (req, res, body) => `${++counter}`,
+      'X-My-Headers': () => `${++counter}`,
     })
 
-  const { headers, rawHeaders } = await got('http://example.com/')
+  const { headers, rawHeaders } = await got('http://example.test/')
   t.equivalent(headers, { 'x-my-headers': '1' })
   t.equivalent(rawHeaders, ['X-My-Headers', '1'])
 
   t.equal(counter, 1)
 
   const { headers: headers2, rawHeaders: rawHeaders2 } = await got(
-    'http://example.com/'
+    'http://example.test/'
   )
   t.equivalent(headers2, { 'x-my-headers': '2' })
   t.equivalent(rawHeaders2, ['X-My-Headers', '2'])
@@ -82,19 +134,7 @@ test('reply headers as function are evaluated on each request', async t => {
   scope.done()
 })
 
-test('reply with content-length header', async t => {
-  const scope = nock('http://example.test')
-    .replyContentLength()
-    .get('/')
-    .reply(200, { hello: 'world' })
-
-  const { headers } = await got('http://example.test/')
-
-  t.equal(headers['content-length'], 17)
-  scope.done()
-})
-
-test('reply with explicit date header', async t => {
+test('replyDate() sends explicit date header with response', async t => {
   const date = new Date()
 
   const scope = nock('http://example.test')
@@ -110,7 +150,7 @@ test('reply with explicit date header', async t => {
 
 // async / got version is returning "not ok test unfinished".
 // https://github.com/nock/nock/issues/1305#issuecomment-451701657
-test('reply with implicit date header', t => {
+test('replyDate() sends date header with response', t => {
   const clock = lolex.install()
   const date = new Date()