generators.md

Generators

In @fluentfixture, streams cannot be initialized directly. To take advantage of the stream's fluent interface, we can use generator functions.

Boolean

bool()

Returns a BooleanStream that produces a boolean value.

Parameter	Type	Default	Description
percentage	Float	0.5	chance causing it to be true

import { bool } from '@fluentfixture/core';

const stream = bool(0.9);

console.log(stream.many(5));
// [true, true, false, true, true]

truthy()

Returns a BooleanStream that always produces true.

import { truthy } from '@fluentfixture/core';

const stream = truthy();

console.log(stream.many(5));
// [true, true, true, true, true]

falsy()

Returns a BooleanStream that always produces false.

import { falsy } from '@fluentfixture/core';

const stream = falsy();

console.log(stream.many(5));
// [false, false, false, false, false]

Number

int()

Returns an NumberStream that produces an integer value.

Parameter	Type	Default	Description
min	Integer	0	lower boundary
max	Integer	1000	upper boundary

import { int } from '@fluentfixture/core';

const stream = int(1, 10)

console.log(stream.many(5));
// [7, 1, 6, 4, 9]

real()

Returns an NumberStream that produces a float value.

Parameter	Type	Default	Description
min	Float	0	lower boundary
max	Float	1000	upper boundary

import { real } from '@fluentfixture/core';

const stream = real(1, 10)

console.log(stream.many(5));
// [9.298, 3.86, 9.31, 8.38, 8.23]

num()

Returns an NumberStream that always produces the given number.

Parameter	Type	Default	Description
value	Number		value

import { num } from '@fluentfixture/core';

const stream = num(1881);

console.log(stream.many(5));
// [1881, 1881, 1881, 1881, 1881]

zero()

Returns an NumberStream that always produces zero.

import { zero } from '@fluentfixture/core';

const stream = zero();

console.log(stream.many(5));
// [0, 0, 0, 0, 0]

one()

Returns an NumberStream that always produces one.

import { one } from '@fluentfixture/core';

const stream = one();

console.log(stream.many(5));
// [1, 1, 1, 1, 1]

String

text()

Returns a StringStream that always produces the given value.

Parameter	Type	Default	Description
str	String		string

import { text } from '@fluentfixture/core';

const stream = text('hello');

console.log(stream.single());
// 'hello'

str()

Returns a StringStream that produces a string.

Parameter	Type	Default	Description
charset	String		included characters
length	Integer	10	target length

import { str } from '@fluentfixture/core';

const stream = str('abc', 10);

console.log(stream.single());
// 'abcca'

hex()

Returns a StringStream that produces a hex string.

Parameter	Type	Default	Description
length	Integer	10	target length

import { hex } from '@fluentfixture/core';

const stream = hex(10);

console.log(stream.single());
// '22c839cce0'

binary()

Returns a StringStream that produces a binary string.

Parameter	Type	Default	Description
length	Integer	10	target length

import { binary } from '@fluentfixture/core';

const stream = binary(10);

console.log(stream.single());
// '1100001110'

octal()

Returns a StringStream that produces an octal string.

Parameter	Type	Default	Description
length	Integer	10	target length

import { octal } from '@fluentfixture/core';

const stream = octal(10);

console.log(stream.single());
// '2025723760'

numeric()

Returns a StringStream that produces a numeric string.

Parameter	Type	Default	Description
length	Integer	10	target length

import { numeric } from '@fluentfixture/core';

const stream = numeric(10);

console.log(stream.single());
// '0843683947'

alphabetic()

Returns a StringStream that produces an alphabetic string.

Parameter	Type	Default	Description
length	Integer	10	target length

import { alphabetic } from '@fluentfixture/core';

const stream = alphabetic(10);

console.log(stream.single());
// 'KlmobUQbyt'

alphanumeric()

Returns a StringStream that produces an alphanumeric string.

Parameter	Type	Default	Description
length	Integer	10	target length

import { alphanumeric } from '@fluentfixture/core';

const stream = alphanumeric(10);

console.log(stream.single());
// 'iZvY8UtXxh'

Date

date()

Returns a DateStream that produces a date.

Parameter	Type	Default	Description
min	Date	yesterday	lower boundary
max	Date	tomorrow	upper boundary

import { date } from '@fluentfixture/core';

const stream = date();

console.log(stream.single());
// Tue Sep 06 2022 11:10:26 GMT+0300 (GMT+03:00)

now()

Returns a DateStream that produces the current date.

import { now } from '@fluentfixture/core';

const stream = now();

console.log(stream.single());
// Tue Sep 06 2022 11:10:26 GMT+0300 (GMT+03:00)

Object

obj()

Returns an ObjectStream that produces an object.

Parameter	Type	Default	Description
model	Object		object model

import { int, obj, pick } from '@fluentfixture/core';

const stream = obj({
    amount: int(1, 100),
    currency: pick(['USD', 'EUR']),
});

console.log(stream.single());
// {amount: 59, currency: 'EUR'}

Utilities

nil()

Returns a Stream that always produces null.

import { nil } from '@fluentfixture/core';

const stream = nil();

console.log(stream.single());
// null

undef()

Returns a Stream that always produces undefined.

import { undef } from '@fluentfixture/core';

const stream = undef();

console.log(stream.single());
// null

val()

Returns a Stream that always produces the given value.

Parameter	Type	Default	Description
value	Any		value

import { val } from '@fluentfixture/core';

const stream = val(5);

console.log(stream.single());
// 5

from()

Returns a Stream that produces the result of the given function.

Parameter	Type	Default	Description
fn	Function		function

import { from } from '@fluentfixture/core';

const stream = from(() => 5);

console.log(stream.single());
// 5

list()

Returns an ArrayStream that produces that contains the given list.

Parameter	Type	Default	Description
arr	Array		array

import { list } from '@fluentfixture/core';

const stream = list([1, 2, 3])
    .map(i => i * 2);

console.log(stream.single());
// [2, 4, 6]

pick()

Returns a Stream that picks an item from the given list.

import { pick } from '@fluentfixture/core';

const stream = pick([1, 2, 3]);

console.log(stream.single());
// 3

sample()

Returns an ArrayStream that takes items from the given list.

Parameter	Type	Default	Description
count	Integer		count

import { sample } from '@fluentfixture/core';

const stream = sample([1, 2, 3], 2);

console.log(stream.single());
// [2, 3]

shuffle()

Returns an ArrayStream that shuffles the given list.

import { shuffle } from '@fluentfixture/core';

const stream = shuffle([1, 2, 3]);

console.log(stream.single());
// [2, 3, 1]