[hyperpolymath]

Summary

statIsFile and statIsDirectory throw ENOENT on a missing path, and host_profile pins that contract. That leaves a Bun-ESM program no way to ask "does this path exist?" without crashing on the answer "no". kyX (metadatastician/kyx) needs exactly that check before it reads inputs and writes outputs. Without it, a missing input gives an uncaught stack trace and the wrong exit status.

Changes

• lib/codegen_deno.ml: new Bun builtin pathExists → fs.existsSync(path). It is true for any existing path, false for a missing one, and never throws. The stat predicates are unchanged; I chose not to flip their pinned ENOENT contract.
• stdlib/Deno.affine: pub extern fn pathExists(path: String) -> Bool, declared beside the stat externs, which is what the builtins↔stdlib consistency test requires.
• tests/codegen-bun/host_profile.{affine,harness.mjs}: pathExists is false for the removed file and true for a directory.

Testing

• tools/run_codegen_bun_tests.sh: fails without the builtin, passes with it (2 harnesses).
• dune build @test/runtest: green, 570 tests.

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Generated by Claude Code

[coderabbitai]

No actionable comments were generated in the recent review.

Summary

Summary by CodeRabbit

• New Features
  • Added a path existence check that returns whether a file or directory exists, without throwing an error for missing paths.

The Deno standard-library bindings add pathExists(path), and Bun code generation lowers it to existsSync(path). The Bun host-profile fixture checks that the wrapper returns false for a missing file and true for an existing directory.

Changes: Bun path existence check

Layer / File(s)	Summary
Bind and test pathExists stdlib/Deno.affine, lib/codegen_deno.ml, tests/codegen-bun/host_profile.affine, tests/codegen-bun/host_profile.harness.mjs	Adds the public binding and Bun lowering. The test fixture exposes exists(path) and checks its results for a missing file and an existing directory.

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Feature

Suggested reviewers: metadatastician

Merge Risk: Minimal · up to ab5de

This adds a non-throwing path existence check for the Bun host profile. It is a small additive change with tests for missing and existing paths, and no merge-blocking risk remains.

Pre-merge checks: 4

Check name	Status	Explanation
Title check		The title names the main change: a new Bun host-profile builtin, pathExists, that checks path existence without throwing. The raw summary, objectives and description all describe this same change, so …
Description check		The description explains the motivation (stat predicates throw ENOENT, so a total existence check is needed), lists the changes to lib/codegen_deno.ml, stdlib/Deno.affine and the host_profile tests, a…
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

Full details: Title check

Explanation

The title names the main change: a new Bun host-profile builtin, pathExists, that checks path existence without throwing. The raw summary, objectives and description all describe this same change, so the title matches the changeset.

Full details: Description check

Explanation

The description explains the motivation (stat predicates throw ENOENT, so a total existence check is needed), lists the changes to lib/codegen_deno.ml, stdlib/Deno.affine and the host_profile tests, and reports test results. It is directly related to the changeset.

• Autofix · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

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Recent review info

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• Run ID: 1c61d630-716c-4e3f-97b5-a7f89de81fa7

Commits

Reviewing files that changed from the base of the PR and between 9799f1d and ab5ded0.

Files selected for processing: 4

• lib/codegen_deno.ml
• stdlib/Deno.affine
• tests/codegen-bun/host_profile.affine
• tests/codegen-bun/host_profile.harness.mjs

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• GitHub Check: CodeRabbit

Additional comments: 1

stdlib/Deno.affine: 1

83-83: Functional Correctness

The standalone mirror is not in this checkout, so there is no export to add.

The comment assumes that packages/affine-deno/mod.js exists and must export every binding in stdlib/Deno.affine. The file does not exist here, and the audit document records the package as not yet created. The new pathExists declaration therefore does not break a standalone consumer that the checkout can provide.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud