├── .editorconfig
├── .gitattributes
├── .github
    ├── funding.yml
    ├── security.md
    └── workflows
    │   └── main.yml
├── .gitignore
├── .npmrc
├── index.d.ts
├── index.js
├── index.test-d.ts
├── license
├── package.json
├── readme.md
└── test.js


/.editorconfig:
--------------------------------------------------------------------------------
 1 | root = true
 2 | 
 3 | [*]
 4 | indent_style = tab
 5 | end_of_line = lf
 6 | charset = utf-8
 7 | trim_trailing_whitespace = true
 8 | insert_final_newline = true
 9 | 
10 | [*.yml]
11 | indent_style = space
12 | indent_size = 2
13 | 


--------------------------------------------------------------------------------
/.gitattributes:
--------------------------------------------------------------------------------
1 | * text=auto eol=lf
2 | 


--------------------------------------------------------------------------------
/.github/funding.yml:
--------------------------------------------------------------------------------
1 | github: sindresorhus
2 | tidelift: npm/p-waterfall
3 | 


--------------------------------------------------------------------------------
/.github/security.md:
--------------------------------------------------------------------------------
1 | # Security Policy
2 | 
3 | To report a security vulnerability, please use the [Tidelift security contact](https://tidelift.com/security). Tidelift will coordinate the fix and disclosure.
4 | 


--------------------------------------------------------------------------------
/.github/workflows/main.yml:
--------------------------------------------------------------------------------
 1 | name: CI
 2 | on:
 3 |   - push
 4 |   - pull_request
 5 | jobs:
 6 |   test:
 7 |     name: Node.js ${{ matrix.node-version }}
 8 |     runs-on: ubuntu-latest
 9 |     strategy:
10 |       fail-fast: false
11 |       matrix:
12 |         node-version:
13 |           - 14
14 |           - 12
15 |     steps:
16 |       - uses: actions/checkout@v2
17 |       - uses: actions/setup-node@v2
18 |         with:
19 |           node-version: ${{ matrix.node-version }}
20 |       - run: npm install
21 |       - run: npm test
22 | 


--------------------------------------------------------------------------------
/.gitignore:
--------------------------------------------------------------------------------
1 | node_modules
2 | yarn.lock
3 | 


--------------------------------------------------------------------------------
/.npmrc:
--------------------------------------------------------------------------------
1 | package-lock=false
2 | 


--------------------------------------------------------------------------------
/index.d.ts:
--------------------------------------------------------------------------------
  1 | /* eslint-disable import/export */
  2 | export type Task<ValueType, ReturnType> = (
  3 | 	previousValue: ValueType
  4 | ) => ReturnType | PromiseLike<ReturnType>;
  5 | 
  6 | export type InitialTask<ReturnType> = () => ReturnType | PromiseLike<ReturnType>;
  7 | 
  8 | /**
  9 | Run promise-returning & async functions in series, each passing its result to the next.
 10 | 
 11 | @param tasks - Functions are expected to return a value. If a `Promise` is returned, it's awaited before continuing with the next task.
 12 | @param initialValue - Value to use as `previousValue` in the first task.
 13 | @returns Resolves when all promises returned from calling the functions in `tasks` are fulfilled, or rejects if any of the promises reject. The fulfilled value is the value returned from the last task.
 14 | 
 15 | @example
 16 | ```
 17 | import pWaterfall from 'p-waterfall';
 18 | 
 19 | const tasks = [
 20 | 	initialValue => getEmoji(initialValue),
 21 | 	previousValue => `I ❤️ ${previousValue}`
 22 | ];
 23 | 
 24 | console.log(await pWaterfall(tasks, 'unicorn'));
 25 | //=> 'I ❤️ 🦄'
 26 | ```
 27 | */
 28 | export default function pWaterfall<ReturnType>(
 29 | 	tasks: readonly [
 30 | 		InitialTask<ReturnType>
 31 | 	]
 32 | ): Promise<ReturnType>;
 33 | export default function pWaterfall<ValueType1, ReturnType>(
 34 | 	tasks: readonly [
 35 | 		InitialTask<ValueType1>,
 36 | 		Task<ValueType1, ReturnType>
 37 | 	]
 38 | ): Promise<ReturnType>;
 39 | export default function pWaterfall<ValueType1, ValueType2, ReturnType>(
 40 | 	tasks: readonly [
 41 | 		InitialTask<ValueType1>,
 42 | 		Task<ValueType1, ValueType2>,
 43 | 		Task<ValueType2, ReturnType>
 44 | 	]
 45 | ): Promise<ReturnType>;
 46 | export default function pWaterfall<ValueType1, ValueType2, ValueType3, ReturnType>(
 47 | 	tasks: readonly [
 48 | 		InitialTask<ValueType1>,
 49 | 		Task<ValueType1, ValueType2>,
 50 | 		Task<ValueType2, ValueType3>,
 51 | 		Task<ValueType3, ReturnType>
 52 | 	]
 53 | ): Promise<ReturnType>;
 54 | export default function pWaterfall<ValueType1, ValueType2, ValueType3, ValueType4, ReturnType>(
 55 | 	tasks: readonly [
 56 | 		InitialTask<ValueType1>,
 57 | 		Task<ValueType1, ValueType2>,
 58 | 		Task<ValueType2, ValueType3>,
 59 | 		Task<ValueType3, ValueType4>,
 60 | 		Task<ValueType4, ReturnType>
 61 | 	]
 62 | ): Promise<ReturnType>;
 63 | export default function pWaterfall<ValueType1, ValueType2, ValueType3, ValueType4, ValueType5, ReturnType>(
 64 | 	tasks: readonly [
 65 | 		InitialTask<ValueType1>,
 66 | 		Task<ValueType1, ValueType2>,
 67 | 		Task<ValueType2, ValueType3>,
 68 | 		Task<ValueType3, ValueType4>,
 69 | 		Task<ValueType4, ValueType5>,
 70 | 		Task<ValueType5, ReturnType>
 71 | 	]
 72 | ): Promise<ReturnType>;
 73 | export default function pWaterfall<
 74 | 	ValueType1,
 75 | 	ValueType2,
 76 | 	ValueType3,
 77 | 	ValueType4,
 78 | 	ValueType5,
 79 | 	ValueType6,
 80 | 	ReturnType
 81 | >(
 82 | 	tasks: readonly [
 83 | 		InitialTask<ValueType1>,
 84 | 		Task<ValueType1, ValueType2>,
 85 | 		Task<ValueType2, ValueType3>,
 86 | 		Task<ValueType3, ValueType4>,
 87 | 		Task<ValueType4, ValueType5>,
 88 | 		Task<ValueType5, ValueType6>,
 89 | 		Task<ValueType6, ReturnType>
 90 | 	]
 91 | ): Promise<ReturnType>;
 92 | export default function pWaterfall<
 93 | 	ValueType1,
 94 | 	ValueType2,
 95 | 	ValueType3,
 96 | 	ValueType4,
 97 | 	ValueType5,
 98 | 	ValueType6,
 99 | 	ValueType7,
100 | 	ReturnType
101 | >(
102 | 	tasks: readonly [
103 | 		InitialTask<ValueType1>,
104 | 		Task<ValueType1, ValueType2>,
105 | 		Task<ValueType2, ValueType3>,
106 | 		Task<ValueType3, ValueType4>,
107 | 		Task<ValueType4, ValueType5>,
108 | 		Task<ValueType5, ValueType6>,
109 | 		Task<ValueType6, ValueType7>,
110 | 		Task<ValueType7, ReturnType>
111 | 	]
112 | ): Promise<ReturnType>;
113 | export default function pWaterfall<ValueType1, ReturnType>(
114 | 	tasks: readonly [
115 | 		Task<ValueType1, ReturnType>
116 | 	],
117 | 	initialValue: ValueType1
118 | ): Promise<ReturnType>;
119 | export default function pWaterfall<ValueType1, ValueType2, ReturnType>(
120 | 	tasks: readonly [
121 | 		Task<ValueType1, ValueType2>,
122 | 		Task<ValueType2, ReturnType>
123 | 	],
124 | 	initialValue: ValueType1
125 | ): Promise<ReturnType>;
126 | export default function pWaterfall<ValueType1, ValueType2, ValueType3, ReturnType>(
127 | 	tasks: readonly [
128 | 		Task<ValueType1, ValueType2>,
129 | 		Task<ValueType2, ValueType3>,
130 | 		Task<ValueType3, ReturnType>
131 | 	],
132 | 	initialValue: ValueType1
133 | ): Promise<ReturnType>;
134 | export default function pWaterfall<ValueType1, ValueType2, ValueType3, ValueType4, ReturnType>(
135 | 	tasks: readonly [
136 | 		Task<ValueType1, ValueType2>,
137 | 		Task<ValueType2, ValueType3>,
138 | 		Task<ValueType3, ValueType4>,
139 | 		Task<ValueType4, ReturnType>
140 | 	],
141 | 	initialValue: ValueType1
142 | ): Promise<ReturnType>;
143 | export default function pWaterfall<ValueType1, ValueType2, ValueType3, ValueType4, ValueType5, ReturnType>(
144 | 	tasks: readonly [
145 | 		Task<ValueType1, ValueType2>,
146 | 		Task<ValueType2, ValueType3>,
147 | 		Task<ValueType3, ValueType4>,
148 | 		Task<ValueType4, ValueType5>,
149 | 		Task<ValueType5, ReturnType>
150 | 	],
151 | 	initialValue: ValueType1
152 | ): Promise<ReturnType>;
153 | export default function pWaterfall<
154 | 	ValueType1,
155 | 	ValueType2,
156 | 	ValueType3,
157 | 	ValueType4,
158 | 	ValueType5,
159 | 	ValueType6,
160 | 	ReturnType
161 | >(
162 | 	tasks: readonly [
163 | 		Task<ValueType1, ValueType2>,
164 | 		Task<ValueType2, ValueType3>,
165 | 		Task<ValueType3, ValueType4>,
166 | 		Task<ValueType4, ValueType5>,
167 | 		Task<ValueType5, ValueType6>,
168 | 		Task<ValueType6, ReturnType>
169 | 	],
170 | 	initialValue: ValueType1
171 | ): Promise<ReturnType>;
172 | export default function pWaterfall<
173 | 	ValueType1,
174 | 	ValueType2,
175 | 	ValueType3,
176 | 	ValueType4,
177 | 	ValueType5,
178 | 	ValueType6,
179 | 	ValueType7,
180 | 	ReturnType
181 | >(
182 | 	tasks: readonly [
183 | 		Task<ValueType1, ValueType2>,
184 | 		Task<ValueType2, ValueType3>,
185 | 		Task<ValueType3, ValueType4>,
186 | 		Task<ValueType4, ValueType5>,
187 | 		Task<ValueType5, ValueType6>,
188 | 		Task<ValueType6, ValueType7>,
189 | 		Task<ValueType7, ReturnType>
190 | 	],
191 | 	initialValue: ValueType1
192 | ): Promise<ReturnType>;
193 | export default function pWaterfall<
194 | 	ValueType1,
195 | 	ValueType2,
196 | 	ValueType3,
197 | 	ValueType4,
198 | 	ValueType5,
199 | 	ValueType6,
200 | 	ValueType7,
201 | 	ValueType8,
202 | 	ReturnType
203 | >(
204 | 	tasks: readonly [
205 | 		Task<ValueType1, ValueType2>,
206 | 		Task<ValueType2, ValueType3>,
207 | 		Task<ValueType3, ValueType4>,
208 | 		Task<ValueType4, ValueType5>,
209 | 		Task<ValueType5, ValueType6>,
210 | 		Task<ValueType6, ValueType7>,
211 | 		Task<ValueType7, ValueType8>,
212 | 		Task<ValueType8, ReturnType>
213 | 	],
214 | 	initialValue: ValueType1
215 | ): Promise<ReturnType>;
216 | export default function pWaterfall(
217 | 	tasks: Iterable<Task<unknown, unknown>>,
218 | 	initialValue?: unknown
219 | ): Promise<unknown>;
220 | 


--------------------------------------------------------------------------------
/index.js:
--------------------------------------------------------------------------------
1 | import pReduce from 'p-reduce';
2 | 
3 | export default async function pWaterfall(iterable, initialValue) {
4 | 	return pReduce(iterable, (previousValue, function_) => function_(previousValue), initialValue);
5 | }
6 | 


--------------------------------------------------------------------------------
/index.test-d.ts:
--------------------------------------------------------------------------------
  1 | /* eslint-disable symbol-description */
  2 | import {expectType} from 'tsd';
  3 | import pWaterfall from './index.js';
  4 | 
  5 | expectType<Promise<string>>(pWaterfall([() => 'I ❤️ unicorn']));
  6 | expectType<Promise<boolean>>(
  7 | 	pWaterfall([() => 'I ❤️ unicorn', (string: string) => true])
  8 | );
  9 | expectType<Promise<number>>(
 10 | 	pWaterfall([
 11 | 		() => 'I ❤️ unicorn',
 12 | 		(string: string) => true,
 13 | 		(boolean: boolean) => 1
 14 | 	])
 15 | );
 16 | expectType<Promise<null>>(
 17 | 	pWaterfall([
 18 | 		() => 'I ❤️ unicorn',
 19 | 		(string: string) => true,
 20 | 		(boolean: boolean) => 1,
 21 | 		(number: number) => null
 22 | 	])
 23 | );
 24 | expectType<Promise<{}>>( // eslint-disable-line @typescript-eslint/ban-types
 25 | 	pWaterfall([
 26 | 		() => 'I ❤️ unicorn',
 27 | 		(string: string) => true,
 28 | 		(boolean: boolean) => 1,
 29 | 		(number: number) => Symbol(),
 30 | 		(symbol: symbol) => ({})
 31 | 	])
 32 | );
 33 | expectType<Promise<string>>(
 34 | 	pWaterfall([
 35 | 		() => 'I ❤️ unicorn',
 36 | 		(string: string) => true,
 37 | 		(boolean: boolean) => 1,
 38 | 		(number: number) => Symbol(),
 39 | 		(symbol: symbol) => ({}),
 40 | 		(object: Record<string, unknown>) => 'foo'
 41 | 	])
 42 | );
 43 | expectType<Promise<number>>(
 44 | 	pWaterfall([
 45 | 		() => 'I ❤️ unicorn',
 46 | 		(string: string) => true,
 47 | 		(boolean: boolean) => 1,
 48 | 		(number: number) => Symbol(),
 49 | 		(symbol: symbol) => ({}),
 50 | 		(object: Record<string, unknown>) => 'foo',
 51 | 		(string: string) => 1
 52 | 	])
 53 | );
 54 | expectType<Promise<symbol>>(
 55 | 	pWaterfall([
 56 | 		() => 'I ❤️ unicorn',
 57 | 		(string: string) => true,
 58 | 		(boolean: boolean) => 1,
 59 | 		(number: number) => Symbol(),
 60 | 		(symbol: symbol) => ({}),
 61 | 		(object: Record<string, unknown>) => 'foo',
 62 | 		(string: string) => 1,
 63 | 		(number: number) => Symbol()
 64 | 	])
 65 | );
 66 | 
 67 | expectType<Promise<string>>(
 68 | 	pWaterfall([previousValue => `I ❤️ ${previousValue}`], 'unicorn')
 69 | );
 70 | expectType<Promise<true>>(
 71 | 	pWaterfall(
 72 | 		[previousValue => `I ❤️ ${previousValue}`, (string: string) => true],
 73 | 		'unicorn'
 74 | 	)
 75 | );
 76 | expectType<Promise<number>>(
 77 | 	pWaterfall(
 78 | 		[
 79 | 			previousValue => `I ❤️ ${previousValue}`,
 80 | 			(string: string) => true,
 81 | 			(boolean: boolean) => 1
 82 | 		],
 83 | 		'unicorn'
 84 | 	)
 85 | );
 86 | expectType<Promise<null>>(
 87 | 	pWaterfall(
 88 | 		[
 89 | 			previousValue => `I ❤️ ${previousValue}`,
 90 | 			(string: string) => true,
 91 | 			(boolean: boolean) => 1,
 92 | 			(number: number) => null
 93 | 		],
 94 | 		'unicorn'
 95 | 	)
 96 | );
 97 | expectType<Promise<{}>>( // eslint-disable-line @typescript-eslint/ban-types
 98 | 	pWaterfall(
 99 | 		[
100 | 			previousValue => `I ❤️ ${previousValue}`,
101 | 			(string: string) => true,
102 | 			(boolean: boolean) => 1,
103 | 			(number: number) => Symbol(),
104 | 			(symbol: symbol) => ({})
105 | 		],
106 | 		'unicorn'
107 | 	)
108 | );
109 | expectType<Promise<string>>(
110 | 	pWaterfall(
111 | 		[
112 | 			previousValue => `I ❤️ ${previousValue}`,
113 | 			(string: string) => true,
114 | 			(boolean: boolean) => 1,
115 | 			(number: number) => Symbol(),
116 | 			(symbol: symbol) => ({}),
117 | 			(object: Record<string, unknown>) => 'foo'
118 | 		],
119 | 		'unicorn'
120 | 	)
121 | );
122 | expectType<Promise<number>>(
123 | 	pWaterfall(
124 | 		[
125 | 			previousValue => `I ❤️ ${previousValue}`,
126 | 			(string: string) => true,
127 | 			(boolean: boolean) => 1,
128 | 			(number: number) => Symbol(),
129 | 			(symbol: symbol) => ({}),
130 | 			(object: Record<string, unknown>) => 'foo',
131 | 			(string: string) => 1
132 | 		],
133 | 		'unicorn'
134 | 	)
135 | );
136 | expectType<Promise<symbol>>(
137 | 	pWaterfall(
138 | 		[
139 | 			previousValue => `I ❤️ ${previousValue}`,
140 | 			(string: string) => true,
141 | 			(boolean: boolean) => 1,
142 | 			(number: number) => Symbol(),
143 | 			(symbol: symbol) => ({}),
144 | 			(object: Record<string, unknown>) => 'foo',
145 | 			(string: string) => 1,
146 | 			(number: number) => Symbol()
147 | 		],
148 | 		'unicorn'
149 | 	)
150 | );
151 | 
152 | expectType<Promise<unknown>>(
153 | 	pWaterfall(
154 | 		new Set([
155 | 			(previousValue: unknown) => {
156 | 				if (typeof previousValue === 'string') {
157 | 					return `I ❤️ ${previousValue}`;
158 | 				}
159 | 			},
160 | 			(string: unknown) => {
161 | 				if (typeof string === 'string') {
162 | 					return true;
163 | 				}
164 | 			},
165 | 			(boolean: unknown) => {
166 | 				if (typeof boolean === 'boolean') {
167 | 					return 1;
168 | 				}
169 | 			},
170 | 			(number: unknown) => {
171 | 				if (typeof number === 'number') {
172 | 					return null;
173 | 				}
174 | 			},
175 | 			(nullValue: unknown) => {
176 | 				if (nullValue === null) {
177 | 					return undefined;
178 | 				}
179 | 			}
180 | 		]),
181 | 		'unicorn'
182 | 	)
183 | );
184 | 
185 | const tasks1 = [() => 'I ❤️ unicorn'] as const;
186 | expectType<Promise<string>>(pWaterfall(tasks1));
187 | 
188 | const tasks2 = [
189 | 	() => 'I ❤️ unicorn',
190 | 	(string: string) => true,
191 | 	(boolean: boolean) => 1,
192 | 	(number: number) => null
193 | ] as const;
194 | expectType<Promise<null>>(pWaterfall(tasks2));
195 | 


--------------------------------------------------------------------------------
/license:
--------------------------------------------------------------------------------
 1 | MIT License
 2 | 
 3 | Copyright (c) Sindre Sorhus <sindresorhus@gmail.com> (https://sindresorhus.com)
 4 | 
 5 | Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
 6 | 
 7 | The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
 8 | 
 9 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
10 | 


--------------------------------------------------------------------------------
/package.json:
--------------------------------------------------------------------------------
 1 | {
 2 | 	"name": "p-waterfall",
 3 | 	"version": "3.0.0",
 4 | 	"description": "Run promise-returning & async functions in series, each passing its result to the next",
 5 | 	"license": "MIT",
 6 | 	"repository": "sindresorhus/p-waterfall",
 7 | 	"funding": "https://github.com/sponsors/sindresorhus",
 8 | 	"author": {
 9 | 		"name": "Sindre Sorhus",
10 | 		"email": "sindresorhus@gmail.com",
11 | 		"url": "https://sindresorhus.com"
12 | 	},
13 | 	"type": "module",
14 | 	"exports": "./index.js",
15 | 	"engines": {
16 | 		"node": ">=12"
17 | 	},
18 | 	"scripts": {
19 | 		"test": "xo && ava && tsd"
20 | 	},
21 | 	"files": [
22 | 		"index.js",
23 | 		"index.d.ts"
24 | 	],
25 | 	"keywords": [
26 | 		"promise",
27 | 		"waterfall",
28 | 		"series",
29 | 		"serial",
30 | 		"sequence",
31 | 		"sequential",
32 | 		"ordered",
33 | 		"task",
34 | 		"tasks",
35 | 		"array",
36 | 		"collection",
37 | 		"iterable",
38 | 		"iterator",
39 | 		"async",
40 | 		"await",
41 | 		"promises",
42 | 		"bluebird"
43 | 	],
44 | 	"dependencies": {
45 | 		"p-reduce": "^3.0.0"
46 | 	},
47 | 	"devDependencies": {
48 | 		"ava": "^3.15.0",
49 | 		"tsd": "^0.14.0",
50 | 		"xo": "^0.38.2"
51 | 	}
52 | }
53 | 


--------------------------------------------------------------------------------
/readme.md:
--------------------------------------------------------------------------------
 1 | # p-waterfall
 2 | 
 3 | > Run promise-returning & async functions in series, each passing its result to the next
 4 | 
 5 | ## Install
 6 | 
 7 | ```
 8 | $ npm install p-waterfall
 9 | ```
10 | 
11 | ## Usage
12 | 
13 | ```js
14 | import pWaterfall from 'p-waterfall';
15 | 
16 | const tasks = [
17 | 	initialValue => getEmoji(initialValue),
18 | 	previousValue => `I ❤️ ${previousValue}`
19 | ];
20 | 
21 | console.log(await pWaterfall(tasks, 'unicorn'));
22 | //=> 'I ❤️ 🦄'
23 | ```
24 | 
25 | ## API
26 | 
27 | ### pWaterfall(tasks, initialValue?)
28 | 
29 | Returns a `Promise` that is fulfilled when all promises returned from calling the functions in `tasks` are fulfilled, or rejects if any of the promises reject. The fulfilled value is the value returned from the last task.
30 | 
31 | #### tasks
32 | 
33 | Type: `Iterable<Function>`
34 | 
35 | Functions are expected to return a value. If a `Promise` is returned, it's awaited before continuing with the next task.
36 | 
37 | #### initialValue
38 | 
39 | Type: `unknown`
40 | 
41 | Value to use as `previousValue` in the first task.
42 | 
43 | ## Related
44 | 
45 | - [p-series](https://github.com/sindresorhus/p-series) - Run promise-returning & async functions in series
46 | - [p-each-series](https://github.com/sindresorhus/p-each-series) - Iterate over promises serially
47 | - [More…](https://github.com/sindresorhus/promise-fun)
48 | 
49 | ---
50 | 
51 | <div align="center">
52 | 	<b>
53 | 		<a href="https://tidelift.com/subscription/pkg/npm-p-waterfall?utm_source=npm-p-waterfall&utm_medium=referral&utm_campaign=readme">Get professional support for this package with a Tidelift subscription</a>
54 | 	</b>
55 | 	<br>
56 | 	<sub>
57 | 		Tidelift helps make open source sustainable for maintainers while giving companies<br>assurances about security, maintenance, and licensing for their dependencies.
58 | 	</sub>
59 | </div>
60 | 


--------------------------------------------------------------------------------
/test.js:
--------------------------------------------------------------------------------
 1 | import test from 'ava';
 2 | import pWaterfall from './index.js';
 3 | 
 4 | test('main', async t => {
 5 | 	const input = [
 6 | 		async previousValue => previousValue + 1,
 7 | 		previousValue => previousValue + 2,
 8 | 		async previousValue => previousValue + 3
 9 | 	];
10 | 
11 | 	t.is(await pWaterfall(input, 0), 6);
12 | });
13 | 
14 | test('throws when one of the input functions rejects', async t => {
15 | 	const fixtureError = new Error('fixture');
16 | 
17 | 	await t.throwsAsync(
18 | 		pWaterfall([() => Promise.reject(fixtureError)]),
19 | 		{message: fixtureError.message}
20 | 	);
21 | });
22 | 


--------------------------------------------------------------------------------