fix: Fix a regression due to Jest having different globals (#1850)

Fix a regression in 11.7.1 due to Jest having different globals: jestjs/jest#2549. Check functions using typeof instead of instanceof.

lib/back.js

@@ -71,7 +71,7 @@ function Back(fixtureName, options, nockedFn) {
   } else if (arguments.length === 2) {
     // If 2nd parameter is a function then `options` has been omitted
     // otherwise `options` haven't been omitted but `nockedFn` was.
-    if (options instanceof Function) {
+    if (typeof options === 'function') {
       nockedFn = options
       options = {}
     }
@@ -89,7 +89,7 @@ function Back(fixtureName, options, nockedFn) {
   debug('context:', context)
 
   // If nockedFn is a function then invoke it, otherwise return a promise resolving to nockDone.
-  if (nockedFn instanceof Function) {
+  if (typeof nockedFn === 'function') {
     nockedFn.call(context, nockDone)
   } else {
     return Promise.resolve({ nockDone, context })
@@ -170,7 +170,7 @@ const record = {
     if (context.isRecording) {
       let outputs = recorder.outputs()
 
-      if (options.afterRecord instanceof Function) {
+      if (typeof options.afterRecord === 'function') {
         outputs = options.afterRecord(outputs)
       }
 

lib/common.js

@@ -315,7 +315,7 @@ const noDuplicatesHeaders = new Set([
  */
 function addHeaderLine(headers, name, value) {
   let values // code below expects `values` to be an array of strings
-  if (value instanceof Function) {
+  if (typeof value === 'function') {
     // Function values are evaluated towards the end of the response, before that we use a placeholder
     // string just to designate that the header exists. Useful when `Content-Type` is set with a function.
     values = [value.name]
@@ -476,7 +476,7 @@ function isStream(obj) {
     obj &&
     typeof obj !== 'string' &&
     !Buffer.isBuffer(obj) &&
-    obj.setEncoding instanceof Function
+    typeof obj.setEncoding === 'function'
   )
 }
 
@@ -500,7 +500,7 @@ function normalizeClientRequestArgs(input, options, cb) {
     input = null
   }
 
-  if (options instanceof Function) {
+  if (typeof options === 'function') {
     cb = options
     options = input || {}
   } else {

lib/intercepted_request_router.js

@@ -113,7 +113,11 @@ class InterceptedRequestRouter {
         }
         this.requestBodyBuffers.push(buffer)
       }
-      if (callback instanceof Function) {
+      // can't use instanceof Function because some test runners
+      // run tests in vm.runInNewContext where Function is not same
+      // as that in the current context
+      // https://github.com/nock/nock/pull/1754#issuecomment-571531407
+      if (typeof callback === 'function') {
         callback()
       }
     } else {
@@ -131,17 +135,17 @@ class InterceptedRequestRouter {
     debug('req.end')
     const { req } = this
 
-    if (chunk instanceof Function) {
+    if (typeof chunk === 'function') {
       callback = chunk
       chunk = null
-    } else if (encoding instanceof Function) {
+    } else if (typeof encoding === 'function') {
       callback = encoding
       encoding = null
     }
 
     if (!req.aborted && !this.playbackStarted) {
       req.write(chunk, encoding, () => {
-        if (callback instanceof Function) {
+        if (typeof callback === 'function') {
           callback()
         }
         this.startPlayback()

lib/interceptor.js

@@ -110,7 +110,7 @@ module.exports = class Interceptor {
 
   reply(statusCode, body, rawHeaders) {
     // support the format of only passing in a callback
-    if (statusCode instanceof Function) {
+    if (typeof statusCode === 'function') {
       if (arguments.length > 1) {
         // It's not very Javascript-y to throw an error for extra args to a function, but because
         // of legacy behavior, this error was added to reduce confusion for those migrating.
@@ -126,7 +126,7 @@ module.exports = class Interceptor {
       }
 
       this.statusCode = statusCode || 200
-      if (body instanceof Function) {
+      if (typeof body === 'function') {
         this.replyFunction = body
         body = null
       }
@@ -215,7 +215,7 @@ module.exports = class Interceptor {
     }
 
     if (reqHeader !== undefined && header !== undefined) {
-      if (reqHeader instanceof Function) {
+      if (typeof reqHeader === 'function') {
         return reqHeader(header)
       } else if (common.matchStringOrRegexp(header, reqHeader)) {
         return true
@@ -250,7 +250,7 @@ module.exports = class Interceptor {
 
     const requestMatchesFilter = ({ name, value: predicate }) => {
       const headerValue = req.getHeader(name)
-      if (predicate instanceof Function) {
+      if (typeof predicate === 'function') {
         return predicate(headerValue)
       } else {
         return common.matchStringOrRegexp(headerValue, predicate)
@@ -317,7 +317,7 @@ module.exports = class Interceptor {
       matchKey = common.normalizeOrigin(proto, options.host, options.port)
     }
 
-    if (this.uri instanceof Function) {
+    if (typeof this.uri === 'function') {
       matches =
         common.matchStringOrRegexp(matchKey, this.basePath) &&
         // This is a false positive, as `uri` is not bound to `this`.
@@ -397,7 +397,7 @@ module.exports = class Interceptor {
     debug('Interceptor queries: %j', this.queries)
     debug('    Request queries: %j', reqQueries)
 
-    if (this.queries instanceof Function) {
+    if (typeof this.queries === 'function') {
       return this.queries(reqQueries)
     }
 
@@ -458,7 +458,7 @@ module.exports = class Interceptor {
       return this
     }
 
-    if (queries instanceof Function) {
+    if (typeof queries === 'function') {
       this.queries = queries
       return this
     }

lib/match_body.js

@@ -26,7 +26,7 @@ module.exports = function matchBody(options, spec, body) {
 
   // try to transform body to json
   let json
-  if (typeof spec === 'object' || spec instanceof Function) {
+  if (typeof spec === 'object' || typeof spec === 'function') {
     try {
       json = JSON.parse(body)
     } catch (err) {
@@ -39,7 +39,7 @@ module.exports = function matchBody(options, spec, body) {
     }
   }
 
-  if (spec instanceof Function) {
+  if (typeof spec === 'function') {
     return spec.call(options, body)
   }
 

lib/playback_interceptor.js

@@ -270,7 +270,7 @@ function playbackInterceptor({
 
     // Evaluate functional headers.
     common.forEachHeader(response.rawHeaders, (value, fieldName, i) => {
-      if (value instanceof Function) {
+      if (typeof value === 'function') {
         response.rawHeaders[i + 1] = value(req, response, responseBody)
       }
     })

lib/recorder.js

@@ -344,10 +344,10 @@ function record(recOptions) {
     const oldEnd = req.end
     req.end = function(chunk, encoding, callback) {
       debug('req.end')
-      if (chunk instanceof Function) {
+      if (typeof chunk === 'function') {
         callback = chunk
         chunk = null
-      } else if (encoding instanceof Function) {
+      } else if (typeof encoding === 'function') {
         callback = encoding
         encoding = null
       }