How to use matchArity method in Jest

Best JavaScript code snippet using jest

express.js

Source:express.js Github

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1/*2 * Copyright 2020 New Relic Corporation. All rights reserved.3 * SPDX-License-Identifier: Apache-2.04 */5'use strict'6/**7 * Express middleware generates traces where middleware are considered siblings8 * (ended on 'next' invocation) and not nested. Middlware are nested below the9 * routers they are mounted to.10 */11module.exports = function initialize(agent, express, moduleName, shim) {12 if (!express || !express.Router) {13 shim.logger.debug('Could not find Express Router, not instrumenting.')14 return false15 }16 shim.setFramework(shim.EXPRESS)17 shim.setErrorPredicate(function expressErrorPredicate(err) {18 return err !== 'route' && err !== 'router'19 })20 if (express.Router.use) {21 wrapExpress4(shim, express)22 } else {23 wrapExpress3(shim, express)24 }25}26function wrapExpress4(shim, express) {27 // Wrap `use` and `route` which are hung off `Router` directly, not on a28 // prototype.29 shim.wrapMiddlewareMounter(express.Router, 'use', {30 route: shim.FIRST,31 wrapper: wrapMiddleware32 })33 shim.wrapMiddlewareMounter(express.application, 'use', {34 route: shim.FIRST,35 wrapper: wrapMiddleware36 })37 shim.wrap(express.Router, 'route', function wrapRoute(shim, fn) {38 if (!shim.isFunction(fn)) {39 return fn40 }41 return function wrappedRoute() {42 const route = fn.apply(this, arguments)43 // Express should create a new route and layer every time Router#route is44 // called, but just to be on the safe side, make sure we haven't wrapped45 // this already.46 if (!shim.isWrapped(route, 'get')) {47 wrapRouteMethods(shim, route, '')48 const layer = this.stack[this.stack.length - 1]49 // This wraps a 'done' function but not a traditional 'next' function. This allows50 // the route to stay on the stack for middleware nesting after the router.51 // The segment will be automatically ended by the http/https instrumentation.52 shim.recordMiddleware(layer, 'handle', {53 type: shim.ROUTE,54 req: shim.FIRST,55 next: shim.LAST,56 matchArity: true,57 route: route.path58 })59 }60 return route61 }62 })63 shim.wrapMiddlewareMounter(express.Router, 'param', {64 route: shim.FIRST,65 wrapper: function wrapParamware(shim, middleware, fnName, route) {66 return shim.recordParamware(middleware, {67 name: route,68 req: shim.FIRST,69 next: shim.THIRD70 })71 }72 })73 wrapResponse(shim, express.response)74}75function wrapExpress3(shim, express) {76 // In Express 3 the app returned from `express()` is actually a `connect` app77 // which we have no access to before creation. We can not easily wrap the app78 // because there are a lot of methods dangling on it that act on the app itself.79 // Really we just care about apps being used as `request` event listeners on80 // `http.Server` instances so we'll wrap that instead.81 shim.wrapMiddlewareMounter(express.Router.prototype, 'param', {82 route: shim.FIRST,83 wrapper: function wrapParamware(shim, middleware, fnName, route) {84 return shim.recordParamware(middleware, {85 name: route,86 req: shim.FIRST,87 next: shim.THIRD88 })89 }90 })91 shim.wrapMiddlewareMounter(express.Router.prototype, 'use', {92 route: shim.FIRST,93 wrapper: wrapMiddleware94 })95 shim.wrapMiddlewareMounter(express.application, 'use', {96 route: shim.FIRST,97 wrapper: wrapMiddleware98 })99 // NOTE: Do not wrap application route methods in Express 3, they all just100 // forward their arguments to the router.101 wrapRouteMethods(shim, express.Router.prototype, shim.FIRST)102 wrapResponse(shim, express.response)103}104function wrapRouteMethods(shim, route, path) {105 const methods = ['all', 'delete', 'get', 'head', 'opts', 'post', 'put', 'patch']106 shim.wrapMiddlewareMounter(route, methods, { route: path, wrapper: wrapMiddleware })107}108function wrapResponse(shim, response) {109 shim.recordRender(response, 'render', {110 view: shim.FIRST,111 callback: function bindCallback(shim, render, name, segment, args) {112 let cbIdx = shim.normalizeIndex(args.length, shim.LAST)113 if (cbIdx === null) {114 return115 }116 const res = this117 let cb = args[cbIdx]118 if (!shim.isFunction(cb)) {119 ++cbIdx120 cb = function defaultRenderCB(err, str) {121 // https://github.com/expressjs/express/blob/4.x/lib/response.js#L961-L962122 if (err) {123 return res.req.next(err)124 }125 res.send(str)126 }127 args.push(cb)128 }129 args[cbIdx] = shim.bindSegment(cb, segment, true)130 }131 })132}133function wrapMiddleware(shim, middleware, name, route) {134 let method = null135 const spec = {136 route: route,137 type: shim.MIDDLEWARE,138 matchArity: true,139 req: shim.FIRST140 }141 if (middleware.lazyrouter) {142 method = 'handle'143 spec.type = shim.APPLICATION144 } else if (middleware.stack) {145 method = 'handle'146 spec.type = shim.ROUTER147 } else if (middleware.length === 4) {148 spec.type = shim.ERRORWARE149 spec.req = shim.SECOND150 }151 // Express apps just pass their middleware through to their router. We do not152 // want to count the same middleware twice, so we check if it has already been153 // wrapped. Express also wraps apps mounted on apps, so we need to check if154 // this middleware is that app wrapper.155 //156 // NOTE: Express did not name its app wrapper until 4.6.0.157 if (shim.isWrapped(middleware, method) || name === 'mounted_app') {158 // Don't double-wrap middleware159 return middleware160 }161 return shim.recordMiddleware(middleware, method, spec)...

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index.js

Source:index.js Github

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1'use strict'2var hasOwnProperty = require('../../util/properties').hasOwn3var util = require('util')4/**5 * Enumeration of argument indexes.6 *7 * Anywhere that an argument index is used, one of these or a direct integer8 * value can be used. These are just named constants to improve readability.9 *10 * Each of these values is also exposed directly on the DatastoreShim class as11 * static members.12 *13 * @readonly14 * @memberof Shim.prototype15 * @enum {number}16 */17var ARG_INDEXES = {18 FIRST: 0,19 SECOND: 1,20 THIRD: 2,21 FOURTH: 3,22 LAST: -123}24exports.ARG_INDEXES = ARG_INDEXES25exports.cast = cast26exports.MiddlewareSpec = MiddlewareSpec27exports.RecorderSpec = RecorderSpec28exports.SegmentSpec = SegmentSpec29exports.WrapSpec = WrapSpec30function cast(Class, spec) {31 return spec instanceof Class ? spec : new Class(spec)32}33function WrapSpec(spec) {34 this.wrapper = typeof spec === 'function' ? spec : spec.wrapper35 this.matchArity = hasOwnProperty(spec, 'matchArity') ? spec.matchArity : false36}37function SegmentSpec(spec) {38 this.name = hasOwnProperty(spec, 'name') ? spec.name : null39 this.recorder = hasOwnProperty(spec, 'recorder') ? spec.recorder : null40 this.inContext = hasOwnProperty(spec, 'inContext') ? spec.inContext : null41 this.parent = hasOwnProperty(spec, 'parent') ? spec.parent : null42 this.parameters = hasOwnProperty(spec, 'parameters') ? spec.parameters : null43 this.internal = hasOwnProperty(spec, 'internal') ? spec.internal : false44 this.opaque = hasOwnProperty(spec, 'opaque') ? spec.opaque : false45}46function RecorderSpec(spec) {47 SegmentSpec.call(this, spec)48 this.stream = hasOwnProperty(spec, 'stream') ? spec.stream : null49 this.promise = hasOwnProperty(spec, 'promise') ? spec.promise : null50 this.callback = hasOwnProperty(spec, 'callback') ? spec.callback : null51 this.rowCallback = hasOwnProperty(spec, 'rowCallback') ? spec.rowCallback : null52 this.after = hasOwnProperty(spec, 'after') ? spec.after : null53 this.callbackRequired =54 hasOwnProperty(spec, 'callbackRequired') ? spec.callbackRequired : null55}56util.inherits(RecorderSpec, SegmentSpec)57function MiddlewareSpec(spec) {58 RecorderSpec.call(this, spec)59 this.req = hasOwnProperty(spec, 'req' ) ? spec.req : ARG_INDEXES.FIRST60 this.res = hasOwnProperty(spec, 'res' ) ? spec.res : ARG_INDEXES.SECOND61 this.next = hasOwnProperty(spec, 'next' ) ? spec.next : ARG_INDEXES.THIRD62 this.type = hasOwnProperty(spec, 'type' ) ? spec.type : 'MIDDLEWARE'63 this.route = hasOwnProperty(spec, 'route' ) ? spec.route : null64 this.params = hasOwnProperty(spec, 'params') ? spec.params : _defaultGetParams65 this.appendPath = hasOwnProperty(spec, 'appendPath') ? spec.appendPath : true66}67util.inherits(MiddlewareSpec, RecorderSpec)68function _defaultGetParams(shim, fn, name, args, req) {69 return req && req.params...

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restify.js

Source:restify.js Github

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1/*2 * Copyright 2020 New Relic Corporation. All rights reserved.3 * SPDX-License-Identifier: Apache-2.04 */5'use strict'6module.exports = function initialize(agent, restify, moduleName, shim) {7 shim.setFramework(shim.RESTIFY)8 shim.setRouteParser(function routeParser(shim, fn, fnName, route) {9 return (route && route.path) || route10 })11 let wrappedServerClass = false12 shim.setErrorPredicate(function restifyErrorPredicate(err) {13 return err instanceof Error14 })15 // Restify extends the core http.ServerResponse object when it's loaded,16 // so these methods are separate from core instrumentation.17 const http = require('http')18 const methods = ['send', 'sendRaw', 'redirect']19 shim.wrap(http.ServerResponse.prototype, methods, function wrapMethod(shim, fn) {20 return function wrappedMethod() {21 const segment = shim.getActiveSegment()22 if (segment) {23 // Freezing the name state prevents transaction names from potentially being24 // manipulated by asynchronous response methods executed as part of res.send()25 // but before `next()` is called.26 segment.transaction.nameState.freeze()27 }28 return fn.apply(this, arguments)29 }30 })31 shim.wrapReturn(restify, 'createServer', wrapCreateServer)32 function wrapCreateServer(shim, fn, fnName, server) {33 // If we have not wrapped the server class, now's the time to do that.34 if (server && !wrappedServerClass) {35 wrappedServerClass = true36 wrapServer(Object.getPrototypeOf(server))37 }38 }39 function wrapServer(serverProto) {40 // These are all the methods for mounting routed middleware.41 const routings = ['del', 'get', 'head', 'opts', 'post', 'put', 'patch']42 shim.wrapMiddlewareMounter(serverProto, routings, {43 route: shim.FIRST,44 endpoint: shim.LAST,45 wrapper: function wrapMiddleware(shim, middleware, name, route) {46 if (shim.isWrapped(middleware)) {47 return middleware48 }49 return shim.recordMiddleware(middleware, {50 matchArity: true,51 route,52 req: shim.FIRST,53 next: shim.LAST54 })55 }56 })57 // These methods do not accept a route, just middleware functions.58 const mounters = ['pre', 'use']59 shim.wrapMiddlewareMounter(serverProto, mounters, function wrapper(shim, middleware) {60 if (shim.isWrapped(middleware)) {61 return middleware62 }63 return shim.recordMiddleware(middleware, {64 matchArity: true,65 req: shim.FIRST,66 next: shim.LAST67 })68 })69 }...

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connect.js

Source:connect.js Github

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1/*2 * Copyright 2020 New Relic Corporation. All rights reserved.3 * SPDX-License-Identifier: Apache-2.04 */5'use strict'6module.exports = function initialize(agent, connect, moduleName, shim) {7 if (!connect) {8 shim.logger.debug('Connect not supplied, not instrumenting.')9 return false10 }11 shim.setFramework(shim.CONNECT)12 shim.setRouteParser(function parseRoute(shim, fn, fnName, route) {13 return route14 })15 const proto =16 (connect && connect.HTTPServer && connect.HTTPServer.prototype) || // v117 (connect && connect.proto) // v218 shim.wrapMiddlewareMounter(proto, 'use', {19 route: shim.FIRST,20 endpoint: shim.LAST,21 wrapper: wrapMiddleware22 })23 wrapConnectExport(shim, connect, !proto)24}25function wrapMiddleware(shim, middleware, name, route) {26 const spec = {27 matchArity: true,28 route: route,29 type: shim.MIDDLEWARE,30 next: shim.LAST,31 req: shim.FIRST32 }33 if (middleware.length === 4) {34 spec.type = shim.ERRORWARE35 spec.req = shim.SECOND36 }37 if (shim.isWrapped(middleware)) {38 // In some cases the middleware will be instrumented by a framework39 // that uses connect (e.g. express v3) and we omit the connect40 // instrumentation.41 return middleware42 }43 return shim.recordMiddleware(middleware, spec)44}45function wrapConnectExport(shim, connect, v3) {46 shim.wrapExport(connect, function wrapExport(shim, fn) {47 const wrapper = shim.wrap(fn, function wrapConnect(shim, _fn) {48 return function wrappedConnect() {49 const res = _fn.apply(this, arguments)50 if (v3) {51 shim.wrapMiddlewareMounter(res, 'use', {52 route: shim.FIRST,53 wrapper: wrapMiddleware54 })55 }56 return res57 }58 })59 shim.proxy(fn, Object.keys(fn), wrapper)60 return wrapper61 })...

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