fix(runtime): preserve byte-view toString with short encodings

[jdalton]

Refs #11519. This partial repair covers the ArrayBuffer-family toString residual left open by #11627. When ArrayBuffer, SharedArrayBuffer, or DataView reaches the shared Buffer dispatcher, its inherited Object.prototype.toString behavior must ignore every argument. The dispatcher now sends these non-indexed byte views through the canonical object-tag path before Buffer encoding and range handling. Buffer's own encoding behavior remains unchanged.

The regressions cover no argument, runtime-built short and literal encodings, extra range arguments, throwing coercion, and Buffer controls. A direct dispatcher test checks byte-view brands with short and heap encoding values and keeps the Buffer hex path as a control.

At final fragment head 6f2f622f228f93ce6d56026b5041c7b456ca2195, a fresh locked build of all three packages passed, the numbered-fragment self-test and live PR gate passed, and the freshly compiled 18-case no-auto fixture again matched pinned Node 26.5.1. The sole change from 5e41d1d is changelog.d/12456-byte-view-tostring.md; source, tests and build inputs are identical. Focused unit, genuine auto-optimization and full-lint evidence below are reused from 5e41d1d, with their original provenance; they were not rerun at the fragment head. Linux validation cannot prove macOS behavior.

At 5e41d1d8b19c030754975afeca52a9c277eda739, the coherent dev build of perry, perry-runtime-static, and perry-stdlib-static passed. The focused direct runtime test passed (1 passed, 5,797 filtered out). The 18-case fixture compiled with --no-auto-optimize and with the default auto-optimization path; both outputs matched pinned Node 26.5.1. The auto-optimization run rebuilt the matching runtime and stdlib archives with the async-bridge feature, without fallback; an initial 180-second build timeout is retained in the evidence, and the longer retry passed.

Validation was performed on Linux. Full scripts/run_lint_gates.sh completed with exit 1: 30 of 137 commands failed and two CI-only commands were skipped. Twenty-eight failures reproduce the saved baseline (25 static/release checks and three warning/Clippy commands). The Windows xwin gate is blocked by proxy HTTP 403. The docs wrapper misses the external target directory; direct generation matches the earlier baseline-attributed outputs, including markdown drift against the tracked empty reference. Full lint is not claimed green. Custom Symbol.toStringTag overrides on registered byte-view receivers and typed-string Symbol.iterator identity remain outside this partial fix.

[coderabbitai]

Note

Currently processing new changes in this PR. This may take a few minutes, please wait...

⚙️ Run configuration

• Configuration used: defaults
• Review profile: CHILL
• Plan: Advanced
• Run ID: b2aff9d3-f27e-480f-b84e-bb244a1a9764

---

📥 Commits

Reviewing files that changed from the base of the PR and between ccbd617 and 6f2f622.

---

📒 Files selected for processing (4)

• changelog.d/12456-byte-view-tostring.md
• crates/perry-runtime/src/object/buffer_dispatch.rs
• crates/perry-runtime/src/value/to_string_buffer_tests.rs
• test-files/test_gap_11519_arraybuffer_to_string_short_encoding.ts

---

 ___________________________________________________________________________
< What can I say except 'You're welcome' for the bugs I found in your code? >
 ---------------------------------------------------------------------------
  \
   \   \
        \ /\
        ( )
      .( o ).

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create a new PR

---

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

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

---

_{Comment @coderabbitai help to get the list of available commands.}