How to use promisifyLifeCycleFunction method in Jest

Best JavaScript code snippet using jest

jasmineAsyncInstall.js

Source:jasmineAsyncInstall.js

...15var Promise = global[Symbol.for('jest-native-promise')] || global.Promise;16function isPromise(obj) {17  return obj && typeof obj.then === 'function';18}19function promisifyLifeCycleFunction(originalFn, env) {20  return function(fn, timeout) {21    if (!fn) {22      return originalFn.call(env);23    }24    const hasDoneCallback = typeof fn === 'function' && fn.length > 0;25    if (hasDoneCallback) {26      // Jasmine will handle it27      return originalFn.call(env, fn, timeout);28    }29    const extraError = new Error(); // Without this line v8 stores references to all closures30    // in the stack in the Error object. This line stringifies the stack31    // property to allow garbage-collecting objects on the stack32    // https://crbug.com/v8/714233    extraError.stack = extraError.stack; // We make *all* functions async and run `done` right away if they34    // didn't return a promise.35    const asyncJestLifecycle = function asyncJestLifecycle(done) {36      const wrappedFn = (0, _isGeneratorFn.default)(fn)37        ? _co.default.wrap(fn)38        : fn;39      const returnValue = wrappedFn.call({});40      if (isPromise(returnValue)) {41        returnValue.then(done.bind(null, null), error => {42          const _isError = (0, _isError3.default)(error),43            checkIsError = _isError.isError,44            message = _isError.message;45          if (message) {46            extraError.message = message;47          }48          done.fail(checkIsError ? error : extraError);49        });50      } else {51        done();52      }53    };54    return originalFn.call(env, asyncJestLifecycle, timeout);55  };56} // Similar to promisifyLifeCycleFunction but throws an error57// when the return value is neither a Promise nor `undefined`58function promisifyIt(originalFn, env, jasmine) {59  return function(specName, fn, timeout) {60    if (!fn) {61      const spec = originalFn.call(env, specName);62      spec.pend('not implemented');63      return spec;64    }65    const hasDoneCallback = fn.length > 0;66    if (hasDoneCallback) {67      return originalFn.call(env, specName, fn, timeout);68    }69    const extraError = new Error(); // Without this line v8 stores references to all closures70    // in the stack in the Error object. This line stringifies the stack71    // property to allow garbage-collecting objects on the stack72    // https://crbug.com/v8/714273    extraError.stack = extraError.stack;74    const asyncJestTest = function asyncJestTest(done) {75      const wrappedFn = (0, _isGeneratorFn.default)(fn)76        ? _co.default.wrap(fn)77        : fn;78      const returnValue = wrappedFn.call({});79      if (isPromise(returnValue)) {80        returnValue.then(done.bind(null, null), error => {81          const _isError2 = (0, _isError3.default)(error),82            checkIsError = _isError2.isError,83            message = _isError2.message;84          if (message) {85            extraError.message = message;86          }87          if (jasmine.Spec.isPendingSpecException(error)) {88            env.pending(message);89            done();90          } else {91            done.fail(checkIsError ? error : extraError);92          }93        });94      } else if (returnValue === undefined) {95        done();96      } else {97        done.fail(98          new Error(99            'Jest: `it` and `test` must return either a Promise or undefined.'100          )101        );102      }103    };104    return originalFn.call(env, specName, asyncJestTest, timeout);105  };106}107function makeConcurrent(originalFn, env, mutex) {108  return function(specName, fn, timeout) {109    if (110      env != null &&111      !env.specFilter({112        getFullName: () => specName || ''113      })114    ) {115      return originalFn.call(env, specName, () => Promise.resolve(), timeout);116    }117    let promise;118    try {119      promise = mutex(() => {120        const promise = fn();121        if (isPromise(promise)) {122          return promise;123        }124        throw new Error(125          `Jest: concurrent test "${specName}" must return a Promise.`126        );127      });128    } catch (error) {129      return originalFn.call(env, specName, () => Promise.reject(error));130    }131    return originalFn.call(env, specName, () => promise, timeout);132  };133}134function jasmineAsyncInstall(globalConfig, global) {135  const jasmine = global.jasmine;136  const mutex = (0, _throat.default)(globalConfig.maxConcurrency);137  const env = jasmine.getEnv();138  env.it = promisifyIt(env.it, env, jasmine);139  env.fit = promisifyIt(env.fit, env, jasmine);140  global.it.concurrent = (env => {141    const concurrent = makeConcurrent(env.it, env, mutex);142    concurrent.only = makeConcurrent(env.fit, env, mutex);143    concurrent.skip = makeConcurrent(env.xit, env, mutex);144    return concurrent;145  })(env);146  global.fit.concurrent = makeConcurrent(env.fit, env, mutex);147  env.afterAll = promisifyLifeCycleFunction(env.afterAll, env);148  env.afterEach = promisifyLifeCycleFunction(env.afterEach, env);149  env.beforeAll = promisifyLifeCycleFunction(env.beforeAll, env);150  env.beforeEach = promisifyLifeCycleFunction(env.beforeEach, env);...

jasmine_async.js

Source:jasmine_async.js

...8                                                                                           * 9                                                                                           */ /**10                                                                                               * This module adds ability to test async promise code with jasmine by11                                                                                               * returning a promise from `it/test` and `before/afterEach/All` blocks.12                                                                                               */function promisifyLifeCycleFunction(originalFn, env) {return function (fn, timeout) {if (!fn) {return originalFn.call(env);}const hasDoneCallback = fn.length > 0;if (hasDoneCallback) {// Jasmine will handle it13      return originalFn.call(env, fn, timeout);} // We make *all* functions async and run `done` right away if they14    // didn't return a promise.15    const asyncFn = function (done) {const returnValue = fn.call({});if (isPromise(returnValue)) {returnValue.then(done.bind(null, null), done.fail);} else {done();}};return originalFn.call(env, asyncFn, timeout);};} // Similar to promisifyLifeCycleFunction but throws an error16// when the return value is neither a Promise nor `undefined`...

jasmine-async.js

Source:jasmine-async.js

...11   * 12   */ /**13       * This module adds ability to test async promise code with jasmine by14       * returning a promise from `it/test` and `before/afterEach/All` blocks.15       */function promisifyLifeCycleFunction(originalFn, env) {return function (fn, timeout) {if (!fn) {return originalFn.call(env);}const hasDoneCallback = fn.length > 0;if (hasDoneCallback) {// Jasmine will handle it16      return originalFn.call(env, fn, timeout);17    }18    // We make *all* functions async and run `done` right away if they19    // didn't return a promise.20    const asyncFn = function (done) {21      const returnValue = fn.call({});22      if (isPromise(returnValue)) {23        returnValue.then(done, done.fail);24      } else {25        done();26      }27    };28    return originalFn.call(env, asyncFn, timeout);29  };30}31// Similar to promisifyLifeCycleFunction but throws an error32// when the return value is neither a Promise nor `undefined`33function promisifyIt(originalFn, env) {34  return function (specName, fn, timeout) {35    if (!fn) {36      const spec = originalFn.call(env, specName);37      spec.pend('not implemented');38      return spec;39    }40    const hasDoneCallback = fn.length > 0;41    if (hasDoneCallback) {42      return originalFn.call(env, specName, fn, timeout);43    }44    const asyncFn = function (done) {45      const returnValue = fn.call({});46      if (isPromise(returnValue)) {47        returnValue.then(done, done.fail);48      } else if (returnValue === undefined) {49        done();50      } else {51        done.fail(52        new Error(53        'Jest: `it` and `test` must return either a Promise or undefined.'));54      }55    };56    return originalFn.call(env, specName, asyncFn, timeout);57  };58}59function makeConcurrent(originalFn, env) {60  return function (specName, fn, timeout) {61    if (env != null && !env.specFilter({ getFullName: () => specName || '' })) {62      return originalFn.call(env, specName, () => Promise.resolve(), timeout);63    }64    let promise;65    try {66      promise = fn();67      if (!isPromise(promise)) {68        throw new Error(69        `Jest: concurrent test "${specName}" must return a Promise.`);70      }71    } catch (error) {72      return originalFn.call(env, specName, () => Promise.reject(error));73    }74    return originalFn.call(env, specName, () => promise, timeout);75  };76}77function install(global) {78  const jasmine = global.jasmine;79  const env = jasmine.getEnv();80  env.it = promisifyIt(env.it, env);81  env.fit = promisifyIt(env.fit, env);82  global.it.concurrent = makeConcurrent(env.it, env);83  global.it.concurrent.only = makeConcurrent(env.fit, env);84  global.it.concurrent.skip = makeConcurrent(env.xit, env);85  global.fit.concurrent = makeConcurrent(env.fit);86  env.afterAll = promisifyLifeCycleFunction(env.afterAll, env);87  env.afterEach = promisifyLifeCycleFunction(env.afterEach, env);88  env.beforeAll = promisifyLifeCycleFunction(env.beforeAll, env);89  env.beforeEach = promisifyLifeCycleFunction(env.beforeEach, env);90}91module.exports = {...

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