Eslint to biome migration

[gregnazario]

Description

Migrates the project from ESLint + Prettier to Biome to significantly speed up the development process by using a single, fast tool for linting, formatting, and import sorting.

This change:

• Replaces ESLint (9.x) with its plugins and Prettier with Biome (2.4.4).
• Removes 7 dependencies (eslint, @typescript-eslint/eslint-plugin, @typescript-eslint/parser, eslint-config-prettier, eslint-plugin-import, globals, prettier) and adds @biomejs/biome.
• Deletes eslint.config.cjs, .prettierrc, .prettierignore, and introduces biome.json.
• Updates package.json scripts for lint, fmt, _fmt, and adds a new check script for comprehensive Biome checks.
• Applies codebase auto-fixes including adding import type annotations, organizing imports, applying node: protocol, and removing obsolete eslint-disable comments.
• Improves performance dramatically: Biome checks 240 files (lint + format + import sorting) in ~200ms, compared to multi-second runs with the previous ESLint + Prettier setup.

Test Plan

1. Run pnpm install to ensure all dependencies are correctly installed.
2. Run pnpm check to verify linting, formatting, and import sorting.
3. Run pnpm lint to verify linting.
4. Run pnpm fmt to apply formatting changes and pnpm _fmt to check formatting.
5. Run pnpm build to ensure the project builds successfully after the changes.
6. Run pnpm test to ensure all tests pass.

Differences

• Lint and Format speedup: 44x faster
• Build output: No change
• Dependency footprint: 26 less transitive dependencies

Related Links

N/A

Checklist

• Have you ran pnpm fmt?
• Have you updated the CHANGELOG.md?

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Pull request overview

Migrates the repo’s JavaScript/TypeScript linting + formatting workflow from ESLint + Prettier to Biome, updating CI scripts and applying large-scale autofixes (imports, Node node: protocol, and lint-disable cleanup) across source and test files.

Changes:

• Replace ESLint/Prettier configuration and dependencies with a Biome configuration (biome.json) and updated pnpm scripts (lint, fmt, check, _fmt).
• Apply mechanical code changes driven by Biome rules (e.g., node: imports, import organization, removal of eslint-disable comments).
• Update CI composite actions and contributor docs (CLAUDE.md / AGENTS.md) to reference Biome-based commands.

Reviewed changes

Copilot reviewed 45 out of 49 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tests/unit/serializer.test.ts	Replace @ts-ignore with @ts-expect-error; remove ESLint suppression comments.
tests/unit/hdKey.test.ts	Replace ESLint suppression with Biome suppression for bracket notation used in tests.
tests/unit/bcsHelper.test.ts	Remove obsolete ESLint suppression comment.
tests/step-definitions/crypto_private_keys.steps.mts	Switch assert import to node:assert; remove ESLint disables.
tests/step-definitions/bcs.steps.mts	Switch assert import to node:assert; formatting updates and switch-case scoping tweaks.
tests/postTest.cjs	Formatting-only change (arrow function style).
tests/move/arguments/publish.json	Formatting-only change.
tests/e2e/transactionManagement/transactionWorker.test.ts	Update Array construction to satisfy new lint/style rules.
tests/e2e/transaction/transactionSubmission.test.ts	Switch assert import to node:assert.
tests/e2e/client/aptosRequest.test.ts	Remove obsolete ESLint suppression comments.
tests/e2e/api/transactionResponse.test.ts	Rename unused variables to satisfy linting without ESLint disables.
tests/e2e/api/digitalAsset.test.ts	Small non-null assertion/style adjustment in test helper.
tests/e2e/ans/publishANSContracts.ts	Switch execSync import to node:child_process; remove ESLint disables.
src/utils/helpers.ts	Remove obsolete ESLint suppression comment.
src/transactions/typeTag/parser.ts	Switch-case scoping adjustment and ESLint suppression cleanup.
src/transactions/typeTag/index.ts	Remove obsolete ESLint disables at top of file.
src/transactions/transactionBuilder/transactionBuilder.ts	Update Array construction style to satisfy lint/style rules.
src/transactions/management/accountSequenceNumber.ts	Remove obsolete ESLint disables around console usage.
src/transactions/instances/transactionPayload.ts	Remove obsolete ESLint disable for unused parameter.
src/transactions/authenticator/account.ts	Remove obsolete ESLint disable for unused parameter.
src/internal/transaction.ts	Replace new Date().getTime() with Date.now(); minor style cleanup.
src/internal/queries/getTableItemsMetadata.graphql	Formatting updates.
src/internal/queries/getTableItemsData.graphql	Formatting updates.
src/internal/queries/getAuthKeysForPublicKey.graphql	Formatting updates (multi-line query signature).
src/internal/queries/getAccountAddressesForAuthKey.graphql	Formatting updates (multi-line query signature).
src/internal/keyless.ts	Replace throw Error(...) with throw new Error(...).
src/internal/account.ts	Replace throw Error(...) with throw new Error(...).
src/core/crypto/privateKey.ts	Remove obsolete ESLint suppression comment.
src/core/crypto/keyless.ts	Remove obsolete ESLint suppression comment.
src/core/crypto/abstraction.ts	Remove obsolete ESLint suppressions for unused parameters.
src/cli/move.ts	Switch Node built-in imports to node: protocol.
src/cli/localNode.ts	Switch Node built-in imports to node: protocol; remove ESLint disables.
src/bcs/serializable/movePrimitives.ts	Remove obsolete ESLint disable at top of file.
src/api/transactionSubmission/helpers.ts	Remove obsolete ESLint suppression comment.
src/api/aptosConfig.ts	Remove obsolete ESLint suppression comments; normalize throw new Error.
src/api/aptos.ts	Formatting-only change in interface extends list.
src/account/EphemeralKeyPair.ts	Remove redundant switch case (Ed25519 handled by default).
src/account/Account.ts	Adjust deprecated helper to call Account.fromPrivateKey directly.
pnpm-lock.yaml	Remove ESLint/Prettier-related packages; add Biome packages.
package.json	Update scripts to Biome; replace devDependencies (ESLint/Prettier → Biome).
eslint.config.cjs	Delete ESLint configuration.
biome.json	Add Biome configuration.
CLAUDE.md	Update developer workflow docs to reference Biome scripts.
CHANGELOG.md	Document migration to Biome and related behavioral changes.
AGENTS.md	Update developer workflow docs to reference Biome scripts.
.prettierrc	Delete Prettier configuration.
.prettierignore	Delete Prettier ignore file.
.github/actions/run-lint/action.yaml	Update lint CI action to run Biome lint.
.github/actions/run-fmt/action.yaml	Update format CI action to run Biome-based formatting check.

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

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[Copilot]

assist.actions.source.organizeImports is set to "off", but the PR description/CHANGELOG mention import sorting via Biome. If import sorting is intended to be part of pnpm check, consider enabling organize-imports in Biome (or adjusting the docs/CHANGELOG to match the actual configuration).