doiuse2

library6.0.0jsnpmunverified

Lint CSS for browser support against the caniuse database. Version 6.0.0 is current stable, released on npm. It integrates as a PostCSS plugin, CLI tool, and transform stream. Differentiators: uses actual caniuse data, supports ignore lists by feature or file globs, outputs human-readable or JSON messages, and works with Stylelint. Alternatives like Autoprefixer add prefixes rather than warn on unsupported features.

testing

npm install doiuse2

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · DOIUSE2

doiuse2

testingjavascriptv6.0.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

DoIUse

✓ import DoIUse from 'doiuse/lib/DoIUse.js'

✗ const DoIUse = require('doiuse').DoIUse

Module uses ESM exports. CommonJS require('doiuse') returns the PostCSS plugin function, not the class.

doiuse (stream)

✓ import doiuse from 'doiuse/stream'

✗ const doiuse = require('doiuse/stream')

Stream entry point available from 'doiuse/stream'. CommonJS require is also supported.

doiuse (CLI)

✓ npx doiuse --browsers "ie >= 9" main.css

✗ doiuse --browsers ie >= 9 main.css without quotes

CLI expects quoted browser string; unquoted may split on spaces.

Demonstrates using doiuse2 as a PostCSS plugin to check CSS against browser support, with ignore options and event handler.

import postcss from 'postcss'; import DoIUse from 'doiuse/lib/DoIUse.js'; const css = 'a { background-size: cover; }'; postcss([ new DoIUse({ browsers: ['ie >= 6', '> 1%'], ignore: ['rem'], ignoreFiles: ['**/normalize.css'], onFeatureUsage: (info) => { console.log(info.message); } }) ]).process(css).then(result => { console.log('Done'); });

Debug

Known issues

breakingMigration from v1 to v2 changed the API from a function to a class. 'browsers' option now accepts an array instead of string.

fix

Use new DoIUse({ browsers: ['ie >= 9'] }) instead of doiuse({ browsers: 'ie >= 9' }).

affects: >=2.0.0

breakingIn v5+, the package was renamed from 'doiuse' to 'doiuse2' on npm due to original maintainer conflict. Import paths changed to 'doiuse2/lib/DoIUse.js'.

fix

Install 'doiuse2' and update imports to 'doiuse2/...'.

affects: >=5.0.0

deprecatedThe CLI option --browsers is deprecated in favor of project .browserslistrc file.

fix

Create a .browserslistrc in your project root instead of passing --browsers.

affects: >=4.0.0

gotchaWhen using CommonJS, require('doiuse') returns the plugin function, not a constructor. Using new with require will throw.

fix

Use var doiuse = require('doiuse'); /* no new */

affects: >=1.0.0

gotchaThe ignore option only works with feature names from data/features.js (e.g., 'rem'), not CSS properties.

fix

Check the features list at https://github.com/clshortfuse/doiuse2/blob/master/data/features.js for valid ignore values.

affects: >=1.0.0

Errors

Common errors & fixes

Error: Cannot find module 'doiuse/lib/DoIUse.js'

Using old package name 'doiuse' instead of 'doiuse2' after version 5.

fix

npm install doiuse2 and import from 'doiuse2/lib/DoIUse.js'.

TypeError: doiuse is not a constructor

Using require('doiuse') then trying to instantiate with 'new' or as class.

fix

Use require('doiuse') directly as a function: postcss([doiuse(opts)]).

Cannot read property 'some' of undefined

Empty or missing browsers option.

fix

Supply browsers option (array of strings) or a .browserslistrc file.

No data found for feature: rem

The 'ignore' list contains an invalid feature name.

fix

Refer to the features list in data/features.js for valid names.

Upgrade

Version history

6.0.0latest on npm

Audit

Dependencies

postcssoptionalpeer dependency for PostCSS plugin usage

caniuse-literequiredprovides browser support data from caniuse

Agent activity

9 hits · last 30 days

node

Resources

githubhttps://github.com/clshortfuse/doiuse2 ↗

packagedoiuse2 ↗

homepagehttps://github.com/clshortfuse/doiuse2 ↗