web3-utils types not compatible with current @types/bn.js

[sebastianst]

With web3-utils 1.0.0-beta.41 and the current @types/bn.js 4.11.4 tsc cannot transpile because the bn.js declaration doesn't have a default export. The following error is thrown

node_modules/web3-utils/types/index.d.ts:23:8 - error TS1192: Module '"/home/.../node_modules/@types/bn.js/index"' has no default export.

23 import BigNumber from 'bn.js';
          ~~~~~~~~~


Found 1 error.

[sebastianst]

It may be worth a try to use

/// <reference types="bn.js" />

instead, where BN is used in the web.js type declarations, and remove the definition of the BN class from web3-utils.

[joshstevens19]

Hey thanks for your issue!

This has been fixed in PR https://github.com/ethereum/web3.js/pull/2280/files

We have to require it else it doesn't work with strict mode (due to the bn.js typing's) so this was the best solution.

This will be released in the next release (should be early next week). A temp fix is to run a post-install script which replaces this line:

import BigNumber from 'bn.js'; > import BigNumber = require('bn.js');

and install @types/bn locally which you can remove once the release comes out.

Thanks