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Add a method to generate tightly packed encodings

See original GitHub issue

Is there a way to replicate the non-standard pack mode used by Solidity in Ethers.js?

My use case is I want to sign an EtherDelta order. This is later validated in the trade function with the following code

bytes32 hash = sha256(tokenGet, amountGet, tokenGive, amountGive, expires, nonce);
if (!(ecrecover(hash,v,r,s) == user ...

So in JavaScript I want to be able to get the non-standard pack mode of the parameters tokenGet, amountGet, tokenGive, amountGive, expires and nonce which can then be passed into a sha256 function. Is that possible?

Issue Analytics

State:
Created 6 years ago
Reactions:2
Comments:12 (5 by maintainers)

Top GitHub Comments

6reactions

ricmoocommented, Nov 23, 2017

Added in https://github.com/ethers-io/ethers.js/commit/8129f0cb8b932662561d8aa799e4963f44d90c75.

ethers.utils.soliditySha256(types, values)
ethers.utils.solidityKeccak256(types, values)

Both types and values should be arrays of the values you wish to work with.

Give it a try and let me know if you have any issues. There are ~2000 test cases for it procedurally generated in the make-contract-events.js file if curious about coverage.

3reactions

ricmoocommented, Jan 23, 2019

@PhABC I think what you are looking for is ethers.utils.solidityPack? It does not support structs though. Do you need struct support?

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