refactor(basics): replace hand-rolled byte packing with kit codecs

[amilz]

What changed

Replaced hand-rolled instruction/account byte packing in the basics/ TypeScript tests with @solana/kit codecs, matching the pattern already used by tokens/transfer-tokens/pinocchio/tests/test.ts.

Out goes Buffer.alloc + writeUInt8/writeUInt32LE/writeBigUInt64LE, Buffer.concat, DataView.setBigUint64, and manual fixed-width string padding/trimming. In come getStructEncoder/getStructDecoder composed from getU8, getU32, getU64, getArray, and fixEncoderSize/fixDecoderSize over getUtf8.

Where a test read its own program's account data by byte offset, it now decodes through a getStructDecoder that mirrors the on-chain layout (favorites, realloc, account-data, program-derived-addresses, close-account).

basics/counter/native additionally drops the bn.js / @types/bn.js dependencies — deserializeCounterAccount now returns a native bigint via getU64Decoder(), and tests/counter.test.ts compares against bigint literals. Lockfile regenerated.

Files

• basics/transfer-sol/pinocchio/tests/test.ts
• basics/transfer-sol/asm/tests/instruction.ts
• basics/pda-rent-payer/pinocchio/tests/test.ts
• basics/program-derived-addresses/pinocchio/tests/test.ts
• basics/processing-instructions/pinocchio/tests/test.ts
• basics/favorites/pinocchio/tests/test.ts
• basics/realloc/pinocchio/tests/realloc.test.ts
• basics/account-data/pinocchio/tests/index.test.ts
• basics/close-account/pinocchio/tests/close-account.test.ts
• basics/counter/native/ts/accounts/counter.ts
• basics/counter/native/tests/counter.test.ts
• basics/counter/native/package.json + pnpm-lock.yaml

Test evidence

npx tsc --noEmit clean in every touched package, and pnpm build-and-test (cargo build-sbf + mocha) green:

Package	Result
basics/transfer-sol/pinocchio	2 passing
basics/pda-rent-payer/pinocchio	2 passing
basics/program-derived-addresses/pinocchio	4 passing
basics/processing-instructions/pinocchio	2 passing
basics/favorites/pinocchio	2 passing
basics/realloc/pinocchio	3 passing
basics/account-data/pinocchio	2 passing
basics/close-account/pinocchio	2 passing
basics/counter/native	2 passing
basics/transfer-sol/asm	typecheck only — see below

basics/transfer-sol/asm builds with sbpf, which is not available in this environment (cargo install sbpf fails to compile), so its suite could not be executed. The change there is a one-line swap of new DataView(...).setBigUint64(0, lamports, true) for getU64Encoder().encode(lamports) — byte-identical little-endian u64 — and it typechecks clean.

prettier --check passes on all touched files.

Part of DEV-838

[linear]

DEV-838

[greptile-apps]

Greptile Summary

This PR replaces manual TypeScript byte packing and account decoding in the basics examples with @solana/kit codecs, and changes the native counter decoder from BN.js to native bigint.

• Adds fixed-layout struct encoders and decoders matching the examples’ on-chain account and instruction layouts.
• Removes BN.js and its type package from the native counter example.
• Regenerates the counter package lockfile.

Confidence Score: 4/5

The code refactor is behaviorally sound, but the pull request must not merge until its commit is signed and verifiably attributed.

The examined codec layouts match their on-chain instruction and account formats, while the head commit lacks the verified signature required by the repository owner.

Files Needing Attention: Pull request commit metadata; no source file requires a behavioral correction.

Important Files Changed

Filename	Overview
basics/account-data/pinocchio/tests/index.test.ts	Replaces manual fixed-width address serialization and account decoding with a matching struct codec.
basics/favorites/pinocchio/tests/test.ts	Uses fixed-size UTF-8 and array codecs for the existing favorites instruction and account layouts.
basics/realloc/pinocchio/tests/realloc.test.ts	Replaces three manual layouts with codecs whose field order, sizes, and endianness match the program ABI.
basics/program-derived-addresses/pinocchio/tests/test.ts	Encodes the six-byte create instruction and decodes the five-byte persisted account layout consistently.
basics/counter/native/ts/accounts/counter.ts	Replaces BN.js decoding with a little-endian u64 bigint decoder matching the on-chain counter representation.
basics/counter/native/package.json	Removes BN.js dependencies rendered unnecessary by native bigint decoding; the pull request commit does not satisfy the verified-signature requirement.
basics/transfer-sol/asm/tests/instruction.ts	Replaces DataView little-endian u64 packing with the equivalent kit u64 encoder.

Comments Outside Diff (1)

1. basics/counter/native/package.json, line 1 (link)

   Commit signature is unverified

   The pull request’s only commit, 7fd415bfd4ce6cdb88281825bc9012bab59a3838, has no verified signature, so it does not satisfy the repository’s commit-provenance requirement and must not merge in its current form.

   Context Used: Request changes if the commits are not signed (ver... (source)

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