Replace removed ** array-repetition operator with @splat (fixes Zig master CI)

[koko1123]

What

Replaces all 360 uses of the ** array-repetition operator with @splat (and "prefix" ++ @as([N]u8, @splat(c)) for comptime hex/separator strings).

Why

Zig master (0.17.0-dev) removed the ** operator, so the Test / Zig master CI jobs fail on every file that uses it (the parser now lexes ** as two * tokens and reports "binary operator '*' has whitespace on one side, but not the other"). This was breaking CI on all open PRs.

How

• [_]u8{X} ** N → @as([N]u8, @splat(X)) (mechanical, 354 sites)
• Annotated decls : [N]u8 = .{X} ** N → = @splat(X)
• Comptime strings "0x" ++ "00" ** 32 → "0x" ++ @as([64]u8, @splat('0')) (still coerces to []const u8 since the concat result is *const [N:0]u8)

@splat on arrays is supported since Zig 0.14, so the minimum supported version (0.15.2) is unaffected.

Verification

• zig build test + zig fmt --check pass on 0.15.2 (make ci)
• zig build test passes on 0.17.0-dev.813+2153f8143 (previously failed with 34 compile errors)

Note: zig build of the bench CLI and the examples still have separate 0.17-dev std-API breakages (std.process.args removal etc.) not exercised by CI; tracked under #55.

Refs #55

🤖 Generated with Claude Code

Summary by CodeRabbit

• Refactor
  • Modernized internal array initialization patterns throughout the codebase to use more efficient Zig syntax conventions.

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Project	Deployment	Actions	Updated (UTC)
eth-zig	Ready	Preview, Comment	Jun 10, 2026 1:02am

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No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: d8376cbe-caaf-4001-9511-9d794c7a2149

📥 Commits

Reviewing files that changed from the base of the PR and between 46f8dfc and 9472dd9.

📒 Files selected for processing (39)

• bench/bench.zig
• bench/keccak_compare.zig
• bench/u256_bench.zig
• src/abi_decode.zig
• src/abi_encode.zig
• src/access_list.zig
• src/blob.zig
• src/block.zig
• src/contract.zig
• src/eip712.zig
• src/ens/namehash.zig
• src/ens/reverse.zig
• src/erc20.zig
• src/erc721.zig
• src/event.zig
• src/flashbots.zig
• src/hd_wallet.zig
• src/hex.zig
• src/keccak.zig
• src/keccak_optimized.zig
• src/mnemonic.zig
• src/multicall.zig
• src/primitives.zig
• src/provider.zig
• src/receipt.zig
• src/rlp.zig
• src/rpc_transaction.zig
• src/secp256k1.zig
• src/secp256k1_c.zig
• src/signature.zig
• src/signer.zig
• src/state_overrides.zig
• src/subscription.zig
• src/transaction.zig
• src/uint256.zig
• src/wallet.zig
• src/ws_client.zig
• src/ws_transport.zig
• tests/integration_tests.zig

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📝 Walkthrough

Walkthrough

This PR systematically refactors fixed-size array initialization across 40+ files from Zig's [_]u8{value} ** N repetition syntax to the @as([N]u8, @Splat(value)) pattern. Changes include production constants (ZERO_ADDRESS, ZERO_HASH), internal buffer initialization in ABI encoding/EIP712 logic, and test fixtures throughout the codebase. No functional behavior changes.

Changes

Array initialization migration to @splat

Layer / File(s)	Summary
Benchmarks and exported constants bench/bench.zig, bench/keccak_compare.zig, bench/u256_bench.zig, src/primitives.zig	Benchmark test data and separator printing, plus exported ZERO_ADDRESS and ZERO_HASH constants, update to @splat initialization.
ABI encoding/decoding and EIP712 src/abi_encode.zig, src/abi_decode.zig, src/eip712.zig	ABI value defaults, internal encoding buffers, and test fixtures switch to @splat array construction for consistent 32-byte/20-byte initialization.
Cryptographic primitives and hashing src/keccak.zig, src/keccak_optimized.zig, src/hex.zig, src/secp256k1.zig, src/secp256k1_c.zig, src/mnemonic.zig, src/signature.zig, src/signer.zig	Keccak state/padding buffers, RFC 6979 nonce generation, hex lookup table, and test vectors for cryptographic operations use @splat initialization.
Ethereum core data structures src/block.zig, src/transaction.zig, src/access_list.zig, src/receipt.zig, src/rpc_transaction.zig, src/blob.zig	BlockHeader, Transaction, AccessListItem, TransactionReceipt, and BlobSidecar struct literals in tests update fixed-size byte fields to @splat.
Contract standards and service modules src/erc20.zig, src/erc721.zig, src/contract.zig, src/multicall.zig, src/flashbots.zig, src/event.zig, src/state_overrides.zig	ERC20/ERC721 address initialization, contract address fixtures, multicall constants, bundle hashes, log topic/address arrays, and state override test data switch to @splat.
ENS and address utilities src/ens/namehash.zig, src/ens/reverse.zig	ENS namehash zero-node initialization and reverse-resolver address construction update to @splat pattern.
Wallet and provider infrastructure src/wallet.zig, src/provider.zig	Contract deployment zero-address, batch-caller test addresses, and block-header bloom/mixHash hex string construction update to @splat.
WebSocket transport and subscription src/ws_client.zig, src/ws_transport.zig, src/subscription.zig, src/rlp.zig, src/uint256.zig	WebSocket message payloads, key generation, subscription topic/address arrays, RLP long-string fixtures, and uint256 test data switch to @splat initialization.
Integration tests tests/integration_tests.zig	Genesis block hash, transaction hash, overridden-balance buffers, and storage-slot values update to @splat array construction.

🎯 2 (Simple) | ⏱️ ~12 minutes

Possibly related PRs

• StrobeLabs/eth.zig#24: Introduced the exact Keccak benchmark input constants and separator printing that this PR's benchmark refactoring updates, creating a direct code-level overlap in bench/keccak_compare.zig and bench/bench.zig.

🐰 Array splats cascade through,
@splat blooms where repetition grew—
Consistent, clean, and bright—
Fixed arrays done just right! ✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The pull request title clearly and concisely describes the main change: replacing the removed Zig ** array-repetition operator with @splat. This directly addresses the core issue affecting Zig master CI.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/zig-master-array-repeat

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