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1.0.4 • Public • Published

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The package allows you to calculate moon phase by date.


There are three methods of phase calculation like Simple, Conway and Sinnot:

const { Simple, Conway, Sinnot } = require("@lab-code/moonphase");

console.log(Simple(10, 2, 2021)); // 28
console.log(Conway(15, 2, 2021)); // 3
console.log(Sinnot(20, 2, 2021)); // 9

The methods return integer value from 0 to 29

Declaration of the methods looks like so:

export declare const Simple: (day: number, month: number, year: number) => number;
export declare const Conway: (day: number, month: number, year: number) => number;
export declare const Sinnot: (day: number, month: number, year: number) => number;

Important note: We are not providing checking of input validation you have to do it by yourself. We can guarantee valid calculation for all methods since 1971 up to 2100 at the moment.


🏃🏽 Instant Value: All basic tools included and configured:

  • TypeScript 4.1
  • ESLint with some initial rules recommendation
  • Jest for fast unit testing and code coverage
  • Type definitions for Node.js and Jest
  • Prettier to enforce consistent code style
  • NPM scripts for common operations
  • Simple example of TypeScript code and unit test
  • .editorconfig for consistent file format
  • Reproducible environments thanks to Volta
  • Example configuration for GitHub Actions and Travis CI

🤲 Free as in speech: available under the APLv2 license.

Getting Started

This project is intended to be used with the latest Active LTS release of Node.js.

Clone repository

To clone the repository use the following commands:

git clone https://github.com/NikitaSmithTheOne/moonphase
cd moonphase
npm install

Available Dev Scripts

  • clean - remove coverage data, Jest cache and transpiled files,
  • build - transpile TypeScript to ES6,
  • build:watch - interactive watch mode to automatically transpile source files,
  • lint - lint source files and tests,
  • test - run tests,
  • test:watch - interactive watch mode to automatically re-run tests

Additional Informations

Why include Volta

Volta’s toolchain always keeps track of where you are, it makes sure the tools you use always respect the settings of the project you’re working on. This means you don’t have to worry about changing the state of your installed software when switching between projects. For example, it's used by engineers at LinkedIn to standarize tools and have reproducible development environments.

I recommend to install Volta and use it to manage your project's toolchain.

Writing tests in JavaScript

Writing unit tests in TypeScript can sometimes be troublesome and confusing. Especially when mocking dependencies and using spies.

This is optional, but if you want to learn how to write JavaScript tests for TypeScript modules.

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npm i @lab-code/moonphase

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  • nikitasmiththeone