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How to use matchArity method in Jest

Best JavaScript code snippet using jest

express.js

Source:express.js

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          //Â 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)...

index.js

Source:index.js

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...

restify.js

Source:restify.js

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  }...

connect.js

Source:connect.js

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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What is Jest Framework
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