feat: ecAdd / ecMul

[obatirou]

Pull Request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no API changes)
• Build-related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Resolves: #856

What is the new behavior?

Wrap ecAdd / ecMul

Does this introduce a breaking change?

• Yes
• No

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This change is 

[obatirou]

blocked by foundry-rs/starknet-foundry#2397

[feltroidprime]

Some note : if ec_add or ec_mul returns None, it shouldn't be interpreted as (0,0) which is a valid way of encoding the point at inifinity. It should be a precompile error

See https://www.evm.codes/precompiled
If the input is not valid, all gas provided is consumed and there is no return data, indicating a precompile contract error. Also, if not enough gas was given, there is no return data.

The Option::None case is reflecting the input is not valid .

[obatirou]

Some note : if ec_add or ec_mul returns None, it shouldn't be interpreted as (0,0) which is a valid way of encoding the point at inifinity. It should be a precompile error

See https://www.evm.codes/precompiled If the input is not valid, all gas provided is consumed and there is no return data, indicating a precompile contract error. Also, if not enough gas was given, there is no return data.

The Option::None case is reflecting the input is not valid .

Thank you for spotting this !
Will make sure to take this into account when working on it again.
This draft PR is not ready as it does not compile due to the blocking issue.

[enitrat]

@obatirou https://github.com/foundry-rs/starknet-foundry/releases/tag/v0.30.0