--- The fozzie repo has now been moved to our fozzie-components mono-repo ---
SCSS Helper Library for Front-End projects that are implementing PIE across JET.
Fozzie is an SCSS Helper Library that's used to help ensure web projects across JET have access to a set of baseline SCSS variables, mixins and functions.
By including this helper library, the consuming web application will have access to our shared PIE Design tokens, as well as common SCSS helper mixins and functions for things like font-size, spacing and setting media queries.
Additionally, some parts of Fozzie are available as compiled CSS to use directly in a web application that may not be using SCSS.
To use the fozzie SCSS helper library, you'll need to ensure a couple of things:
-
That you use
dart-sassto compile your Sass. The sass module uses dart-sass by default now, so if you use the latest version of this module, you'll be good-to-go.node-sasssupport in Sass has been officially deprecated and as this library uses up-to-date Sass syntax (namely@useand@forward, rather than@import), it won't work when compiling withnode-sass. -
Your build tool supports importing via the
node_modulesfolder.Both Webpack and Parcel support this by setting
includePathsto point to thenode_modulesfolder. More info on setting this up in your project can be found in the FAQ's (TODO: Add Link to docs).
-
Install the fozzie module using NPM or Yarn:
yarn add @justeat/fozzie
-
Then within your Sass files, you will need to import this module.
@use 'fozzie' as f;
Once you have imported fozzie into your Sass, you'll have access to the fozzie variables, mixins and functions, which can be used as in the following example:
.myCoolComponent {
// Using PIE Variables
background: f.$color-background-default;
border-radius: f.$radius-rounded-b;
// Using helper mixins
@include f.font-size('body-l');
// Using helper functions
padding: f.spacing('b');
// Using media query helper
@include media('>mid') {
padding: f.spacing('c');
}
]Fozzie offers a few pre-compiled CSS files for web applications not using SCSS. These are:
fozzie-reset.css- our normalize and reset stylesfozzie-typography.css- our typographic stylesfozzie-utilities.css- trumps and utility classes to use
All of the CSS files come as regular or minified CSS and include sourcemaps.
Example of using them in a project (note: you can also pull these from dist/css if you have installed Fozzie in the project):
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>A JustEat Marketing Site</title>
<!-- use fozzie CSS files to provide base styles and utilities classes used by the cookie banner -->
<link rel="stylesheet" href="https://unpkg.com/@justeat/[email protected]/dist/css/fozzie-reset.css" />
<link rel="stylesheet" href="https://unpkg.com/@justeat/[email protected]/dist/css/fozzie-typography.css" />
<link rel="stylesheet" href="https://unpkg.com/@justeat/[email protected]/dist/css/fozzie-utilities.css" />
</head>
<body>
<h1>Hello World!</h1>
</body>
</html>We currently test our SCSS in two ways:
- Unit testing
- Snapshot testing
We use a library called sass-true to enable writing unit tests for sass functions and mixins. These tests live in src/test/scss/unit-tests. We should use these as a means of documentation for our functions and mixins, as well as ensuring that API regressions aren't introduced.
We use Jest to write snapshot tests of the compiled CSS for parts of Fozzie. These live in src/test/scss/snapshot-tests. Snapshot tests provide a means of ensuring that no unexpected styles will be introduced for consumers of the library. They can also be used to ensure that the compiled CSS is 100% valid, or to make sure there's simply nothing unexpected being rendered.
To write these tests, we can either import an SCSS file or write a line of SCSS we'd like to test and compile it using the compileToCss.js module. We can then use Jest to snapshot test the outputted string.