refactor(oxfmt): Resolve options on each path, preparing for .editorconfig support

[leaysgur]

Refactoring for #15850

Before this PR

• The config file and its option values were resolved only once at the beginning
• They were kept for OxcFormatter and also being cached via setupConfig() for ExternalFormatter
• When calling SourceFormatter.format(), it always referenced those values

After this PR

• The config file and its option values are resolved only once at the beginning
• Those values are still kept as before
  • But, this is for a fast path when there are no per-path overrides in .editorconfig
• When calling SourceFormatter.format()
  • If .editorconfig exists and has per-path overrides, they are re-resolved per path
  • Otherwise, it continues to reference the initially cached values

We only support the root .editorconfig, but since glob-based per-path overrides can be written there, we have to resolve options on each path. Some performance impact is unavoidable.

However, in scenarios where .editorconfig doesn't exist, or exists but has no per-path overrides, the cost is limited to just cloning the cached values per path.

[leaysgur]

• test(oxfmt): Add tests for .editorconfig support #17044
• feat(oxfmt): Respect single nearest .editorconfig #17043
• refactor(oxfmt): Clean up src-js files and directories #17040
• fix(oxfmt): Update api FormatOptions type with & Record<string, unknown> #17036
• refactor(oxfmt): Resolve options on each path, preparing for .editorconfig support #16991 👈 (View in Graphite)
• main

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[Copilot]

Pull request overview

This PR refactors the configuration resolution system in oxfmt to prepare for .editorconfig support. The key change is moving from resolving configuration once at the start to resolving it per-file, enabling future per-path overrides from .editorconfig.

Key Changes

• Introduced ConfigResolver and ResolvedOptions types to handle configuration resolution per file path
• Refactored external formatter callbacks to accept options on each call rather than during initialization
• Updated all formatting entry points to resolve options per-file instead of using cached global options

Reviewed changes

Copilot reviewed 12 out of 13 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
apps/oxfmt/src/core/config.rs	Introduced ConfigResolver and ResolvedOptions for per-file configuration resolution; moved from single load_config() to resolver pattern
apps/oxfmt/src/core/format.rs	Updated SourceFormatter::format() to accept ResolvedOptions parameter; formatting methods now receive options per call
apps/oxfmt/src/core/external_formatter.rs	Renamed callback from setup_config to init; formatter methods now accept options parameter on each call
apps/oxfmt/src/stdin/mod.rs	Updated to use ConfigResolver and resolve options per stdin file entry
apps/oxfmt/src/main_napi.rs	Updated NAPI API to use ConfigResolver and resolve options before formatting
apps/oxfmt/src/cli/format.rs	Updated CLI runner to create ConfigResolver and pass to FormatService
apps/oxfmt/src/cli/service.rs	Updated service to accept ConfigResolver and resolve options per file in parallel formatting
apps/oxfmt/src-js/prettier-proxy.ts	Removed config setup from pool initialization; options now passed on each format call
apps/oxfmt/src-js/prettier-worker.ts	Removed workerData config; workers now receive options with each task
apps/oxfmt/src-js/index.ts	Updated to use initExternalFormatter instead of setupConfig
apps/oxfmt/src-js/cli.ts	Updated callback reference to initExternalFormatter
apps/oxfmt/src-js/bindings.d.ts	Updated TypeScript type definitions for new callback signatures

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[Dunqing]

Need to take a look at the Copilot review

[leaysgur]

@Dunqing Oh, sorry, I missed that and resolved!

• options mutation: It's safe and updated comment in the later PR
• clone() perf: I locally tested Arc before, but it was not so effective, but I will check again later

[graphite-app]

Merge activity

• Dec 18, 10:40 AM UTC: Dunqing added this pull request to the Graphite merge queue.
• Dec 18, 10:50 AM UTC: Merged by the Graphite merge queue.