sliceHex bug

[drortirosh]

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• I checked there isn't already an issue for the bug I encountered.

Viem Version

2.37

Current Behavior

sliceHex("0x12345678",1,0) = "0x" // ok, supports zero length hex values

sliceHex("0x12345678",4,0)  // reverts on "out of bounds"

This should not revert, but return an empty hex string (e.g. given calldata, I want to extract the params block)

Expected Behavior

No response

Steps To Reproduce

No response

Link to Minimal Reproducible Example

No response

Anything else?

No response

[jxom]

I don't think this is really a "bug", but more of a behavior. This will be a breaking change if we change the behavior, but we can consider it for Viem v3.

[drortirosh]

Do you have another way to extract the parameters block from calldata ? the method sig is 4 bytes, followed by a parameters block which is zero or more bytes.

also, consider

a = '0xaaaa'
b = '0xbbbb'

c = hexConcat( [a,b] )
extractB = hexSlice(c, size(a))

This would concatenate a and b, and then extract b again.
it works for any size of a and b - except when size(b)=0 - when it reverts.