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Invalid TypeScript Type (Default Export)

See original GitHub issue

PostCSS exports default type as seen in the type file:

https://github.com/postcss/postcss/blob/master/lib/postcss.d.ts

However that is certainly not the case because a code calling default exported type will not run:

import postcss from 'postcss';

        const postcssResult = await postcss([autoprefixer])
            .process(sassResult.css, postcssOptions);

TypeError: postcss_1.default is not a function

Instead, shouldn’t the TypeScript declaration use export = ?

https://www.typescriptlang.org/docs/handbook/modules.html#export--and-import--require

Not to mention, calling import postcss = require('postcss'); from TypeScript will not compile anymore due to this type declaration change!

Workaround for those affected by this issue: revert back to PostCSS 7

Issue Analytics

State:
Created 3 years ago
Reactions:2
Comments:9 (7 by maintainers)

Top GitHub Comments

1reaction

Semigradskycommented, Oct 9, 2020

Yes, move from “commonjs .js and .mjs” to “esm .js and .cjs” should help. In this case typings will be correct.

1reaction

Semigradskycommented, Oct 8, 2020

TS doesn’t support .mjs files yet, so current typings lie. Typings should be rewritten to commonjs declare namespace ... and export = X style 😞

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