feat: add Amsterdam hardfork mapping and default to Osaka (#14683)

[Dargon789]

feat: add Amsterdam hardfork mapping to SpecId

Add EthereumHardfork::Amsterdam => SpecId::AMSTERDAM mapping in spec_id_from_ethereum_hardfork. Without this, Amsterdam would hit the unreachable!() catch-all arm.

The default evm_version is already set to Osaka.

Amp-Thread-ID: https://ampcode.com/threads/T-019e113f-5bda-711b-8ec5-4841042ba62c

Motivation

Solution

PR Checklist

• Added Tests
• Added Documentation
• Breaking changes

Summary by Sourcery

Map the Amsterdam Ethereum hardfork to its corresponding SpecId and cover it with tests.

Bug Fixes:

• Prevent Amsterdam hardfork lookups from triggering the unreachable catch-all in spec_id_from_ethereum_hardfork.

Tests:

• Add a unit test asserting that the Amsterdam hardfork resolves to SpecId::AMSTERDAM.

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[sourcery-ai]

Reviewer's guide (collapsed on small PRs)

Reviewer's Guide

Maps the new Ethereum Amsterdam hardfork to its corresponding EVM SpecId and extends the hardfork-to-spec mapping test coverage to include Amsterdam, preventing the code from falling into the unreachable catch-all arm.

Class diagram for Ethereum hardfork to SpecId mapping update

classDiagram
    class EthereumHardfork {
        <<enum>>
        Frontier
        Homestead
        Byzantium
        Constantinople
        Istanbul
        Berlin
        London
        Shanghai
        Cancun
        Prague
        Osaka
        Amsterdam
        Bpo3
        Bpo4
        Bpo5
    }

    class SpecId {
        <<enum>>
        FRONTIER
        HOMESTEAD
        BYZANTIUM
        CONSTANTINOPLE
        ISTANBUL
        BERLIN
        LONDON
        SHANGHAI
        CANCUN
        PRAGUE
        OSAKA
        AMSTERDAM
    }

    class HardforkSpecMapper {
        +spec_id_from_ethereum_hardfork(hardfork: EthereumHardfork) SpecId
    }

    EthereumHardfork --> HardforkSpecMapper : input
    HardforkSpecMapper --> SpecId : output

    HardforkSpecMapper ..> SpecId : maps Amsterdam to AMSTERDAM

Loading

File-Level Changes

Change	Details	Files
Map EthereumHardfork::Amsterdam to SpecId::AMSTERDAM in the hardfork-to-spec resolver and update tests accordingly.	Extend spec_id_from_ethereum_hardfork match to return SpecId::AMSTERDAM when given EthereumHardfork::Amsterdam, instead of hitting the unreachable catch-all arm. Add an assertion in the hardfork mapping tests to verify that EthereumHardfork::Amsterdam maps to SpecId::AMSTERDAM, alongside existing checks for Cancun, Prague, and Osaka.	crates/evm/hardforks/src/lib.rs

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[snyk-io]

✅ Snyk checks have passed. No issues have been found so far.

Status	Scan Engine	Critical	High	Medium	Low	Total (0)
🔚	Open Source Security	0	0	0	0	0 issues

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[mergify]

⚠️ The sha of the head commit of this PR conflicts with #533. Mergify cannot evaluate rules on this PR. Once #533 is merged or closed, Mergify will resume processing this PR. ⚠️

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Project	Deployment	Actions	Updated (UTC)
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[gemini-code-assist]

Code Review

This pull request adds support for the Amsterdam hardfork by mapping EthereumHardfork::Amsterdam to SpecId::AMSTERDAM and adding a corresponding test case. The reviewer suggested mapping the Bpo3, Bpo4, and Bpo5 variants to SpecId::AMSTERDAM as well, rather than leaving them as unimplemented, to avoid potential runtime panics.