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import type {Person} from './types';

export default function setName(person: Person, name: string): Person {
  return {
    ...person,
    name
  };
}

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import {sampleOne} from 'babel-plugin-transform-flow-to-gen/api';

type Person = {
  name: string,
  age: number,
  setName: (name: string) => Person
};

const person = sampleOne(Person());

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var testcheck = require('testcheck');
var gen = testcheck.gen;

testcheck.check(testcheck.property(
  [gen.int, gen.int], // generate two random integers
  function (a, b) {
    // check that the sum of the integers is always greater than any one number
    return a + b >= a && a + b >= b;
  }
));

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{ result: false,
  'failing-size': 2,
  'num-tests': 3,
  fail: [ 2, -1 ],
  shrunk:
   { 'total-nodes-visited': 2,
     depth: 1,
     result: false,
     smallest: [ 0, -1 ] } }

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const personGen = gen.object({
  name: gen.string,
  age: gen.int,
  orders: gen.array(gen.object({
    trackingId: gen.int,
    name: gen.string
  })),
  // ...
});

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// @flow

function giveMeStrings(arr: string[]): string {
  // do something with the array of strings
}

giveMeStrings('hello', 'goodbye');
/*
ERROR:
7: giveMeStrings('hello', 'goodbye');

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require('jasmine-check').install();

describe('adding numbers', () => {
  check.it('the sum is always greater than the parts', [gen.int, gen.int], (a, b) => {
    expect(a + b).toBeGreaterThanOrEqual(a);
    expect(a + b).toBeGreaterThanOrEqual(b);
  });
});
// FAIL
// ● adding numbers › the sum is always greater than the parts ( 0, -1 )

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import type {Person} from './types';

export default function setName(person: Person, name: string): Person {
  return {
    ...person,
    name
  };
}

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import {sampleOne} from 'babel-plugin-transform-flow-to-gen/api';
import type {Developer, JavaScript} from './types';

const javaScriptDevGen = Developer(JavaScript());

const dev = sampleOne(javaScriptDevGen);

console.log(dev);
// { name: 't', age: 4, preferredLanguage: { name: 'javascript' } }

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export default function append<T>(arr: T[], val: T): T[] {
  return [...arr, val];
}