fixturify-project

What is fixturify-project?

The fixturify-project npm package is a utility for creating and managing file system fixtures in a programmatic way. It is particularly useful for testing and development purposes, allowing you to easily set up and tear down file system states.

What are fixturify-project's main functionalities?

Creating a new project

This feature allows you to create a new project with a specified structure. In this example, a new project named 'my-app' is created with a single file 'index.js' containing a simple console log statement.

const { Project } = require('fixturify-project');
const project = new Project('my-app', {
  files: {
    'index.js': 'console.log("Hello, world!");'
  }
});
project.writeSync();

Adding files to an existing project

This feature allows you to add new files to an existing project. In this example, a new file 'new-file.js' is added to the 'my-app' project with a console log statement.

const { Project } = require('fixturify-project');
const project = new Project('my-app');
project.files['new-file.js'] = 'console.log("New file");';
project.writeSync();

Reading project files

This feature allows you to read the files of an existing project. In this example, the files of the 'my-app' project are read and logged to the console.

const { Project } = require('fixturify-project');
const project = new Project('my-app');
project.readSync();
console.log(project.files);

Deleting files from a project

This feature allows you to delete files from an existing project. In this example, the 'index.js' file is deleted from the 'my-app' project.

const { Project } = require('fixturify-project');
const project = new Project('my-app');
delete project.files['index.js'];
project.writeSync();

Other packages similar to fixturify-project

mock-fs

The mock-fs package allows you to mock the file system in Node.js. It is useful for testing purposes, as it lets you create, read, and manipulate a virtual file system without affecting the real file system. Compared to fixturify-project, mock-fs focuses more on mocking the file system for testing rather than creating and managing project structures.

memfs

The memfs package provides an in-memory file system that can be used for testing and development. It allows you to create, read, and manipulate files and directories in memory. Compared to fixturify-project, memfs is more focused on providing an in-memory file system rather than managing project structures.

fs-extra

The fs-extra package extends the native Node.js file system module with additional methods for easier file and directory manipulation. It includes methods for copying, moving, and removing files and directories. Compared to fixturify-project, fs-extra provides more general file system utilities rather than focusing on project structure management.

README

node-fixturify-project

When implementing JS build tooling it is common to have complete projects as fixture data. Unfortunately fixtures committed to disk can be somewhat to maintain and augment.

Basic Usage

yarn add fixturify-project

const { Project } = require('fixturify-project');
const project = new Project('rsvp', '3.1.4', {
  files: {
    'index.js': 'module.exports = "Hello, World!"',
  },
});

project.addDependency('mocha', '5.2.0');
project.addDependency('chai', '5.2.0');

project.pkg; // => the contents of package.json for the given project
project.files; // => read or write the set of files further

// if you don't set this, a new temp dir will be made for you when you writeSync()
project.baseDir = 'some/root/';

project.writeSync();

// after writeSync(), you can read project.baseDir even if you didn't set it
expect(fs.existsSync(join(project.baseDir, 'index.js'))).to.eql(true);

The above example produces the following files (and most importantly the appropriate file contents:

some/root/package.json
some/root/index.js
some/root/node_modules/mocha/package.json
some/root/node_modules/chai/package.json

Nesting Dependencies

addDependency returns another Project instance, so you can nest arbitrarily deep:

const { Project } = require('fixturify-project');

let project = new Project('rsvp');
let a = project.addDependency('a');
let b = a.addDependency('b');
let c = b.addDependency('c');

project.writeSync();

Which produces:

$TMPDIR/xxx/package.json
$TMPDIR/xxx/index.js
$TMPDIR/xxx/node_modules/a/package.json
$TMPDIR/xxx/node_modules/a/node_modules/b/package.json
$TMPDIR/xxx/node_modules/b/node_modules/b/node_modules/c/package.json

Linking to real dependencies

Instead of creating all packages from scratch, you can link to real preexisting packages. This lets you take a real working package and modify it and its dependencies and watch how it behaves.

const { Project } = require('fixturify-project');

let project = new Project();
let a = project.addDependency('a');

// explicit target
project.linkDependency('b', { target: '/example/b' });

// this will follow node resolution rules to lookup "c" from "../elsewhere"
project.linkDependency('c', { baseDir: '/example' });

// this will follow node resolution rules to lookup "my-aliased-name" from "../elsewhere"
project.linkDependency('d', { baseDir: '/example', resolveName: 'my-aliased-name' });

project.writeSync();

Produces:

$TMPDIR/xxx/package.json
$TMPDIR/xxx/index.js
$TMPDIR/xxx/node_modules/a/package.json
$TMPDIR/xxx/node_modules/a/node_modules/b -> /example/b
$TMPDIR/xxx/node_modules/b/node_modules/c -> /example/node_modules/c
$TMPDIR/xxx/node_modules/b/node_modules/d -> /example/node_modules/my-aliased-name

When constructing a whole Project from a directory, you can choose to link all dependencies instead of copying them in as Projects:

let project = Project.fromDir('./sample-project', { linkDeps: true });
project.files['extra.js'] = '// stuff';
project.write();

This will generate a new copy of sample-project, with symlinks to all its original dependencies, but with "extra.js" added.

By default, linkDeps will only link up dependencies (which is appropriate for libraries). If you want to also include devDependencies (which is appropriate for apps) you can use linkDevDeps instead.