Idenfity if a package has a `sideEffects: false` field in package.json

[pastelsky]

Idenfity if a package has a `sideEffects: false` field in package.json

[pastelsky]

I've added supports for indexing the sideEffects field for all new package searches. Will add support for surfacing this in the UI when webpack@4 becomes stable.

[pastelsky]

Hi @TheLarkInn. Thanks for writing in. What kind of improvements in size does one generally see when using a sideEffects:true package versus otherwise? Also, which webpack versions support this at the moment?

[TheLarkInn]

Potentially could add the annotation here:

bundlephobia/index.js

Lines 316 to 324 in d8202a9

	const body = {
	error: {
	code: 'MissingDependencyError',
	message: `This package (or this version) uses ${missingModules}, ` +
	`but does not specify ${missingModules.length > 1 ? 'them' :
	'it' }<br /> either as a dependency or a peer dependency`,
	details: err,
	},
	}

[TheLarkInn]

Hi there! The sizes can be incredibly significant. With lodash-es, a single import with sideEffects: false now in their package.json takes a 60kb hit to 1-2kb. However not every library will exhibit this behavior. Also it will be as of webpack 4 and on.

[pastelsky]

With lodash-es, a single import with sideEffects: false now in their package.json takes a 60kb hit to 1-2kb

Does the difference hold in addition to the existing way of treeshaking using jsnext:main / module fields? i.e.

[machineloop]

I believe Wepback@4 has been released, is this available?

[pastelsky]

This is available in the quick info bar just below the search input. 🎊