lint!: upgrade perfectionist

[KSXGitHub]

Upgrades perfectionist from 0.0.0-rc.7 to commit 3ca7f01 (current master). The branch went through several rounds of upstream churn, including a major redesign of macro_argument_binding in KSXGitHub/perfectionist#52, a split of single_letter_names into per-rule config keys, and the addition of derive_ordering, arc_rc_clone, prefer_raw_string, and non_exhaustive_error. Final state below; commit history records the intermediate stops.

derive_ordering (enabled)

Configured for prefix_then_alphabetical with an explicit prefix that encodes the project convention: Debug, formatting/error derives, defaults (Default, SmartDefault), Clone/Copy, comparison and Hash, reference wrappers, conversions, iteration, arithmetic operator pairs and folds, integer-format derives. Anything not in the prefix (Setters, Parser, …) falls alphabetically after. 20 derive lists reordered to satisfy it.

macro_argument_binding (enabled, configured)

The AllowAndDeny default plus two config knobs:

• deny_extra = ["debug_assert_op", "debug_assert_op_expr"] enrolls the assert-cmp family alongside debug_assert*.
• allow_extra = ["bump", "link", "make_const", "symlink", "test_case", "visualize"] catalogues the project's user-defined macros, all of which expand each top-level argument exactly once.

single_letter_* family (enabled)

• Renamed Api::starts_with's a / b params to path / prefix; closure param r → range in usage_md.
• extra_trivial_callback_methods = ["sort_reflection_by"] for the project-private comparator helper.

arc_rc_clone, prefer_raw_string (enabled)

• progress.clone() → Arc::clone(&progress) in reporter::progress_and_error_reporter.
• Four string literals containing escaped quotes rewritten as raw strings in reporter::error_report::text_report and tests::cli_errors.

non_exhaustive_error (not enabled)

Briefly enabled mid-PR. The experiment caught a real bug — bytes_format::parsed_value::ParsedValue was deriving derive_more::Error despite not being an error type — which is fixed by dropping that derive. The rule also asked for #[non_exhaustive] on args::fraction::ConversionError and args::fraction::FromStrError, but both are explicitly exhaustive (their constructor and parser each have a closed set of failure modes), so adding #[non_exhaustive] would have been a misstatement. Retired the rule and reverted the two annotations. The ParsedValue cleanup remains.

Plumbing

• #![cfg_attr(dylint_lib = "perfectionist", feature(register_tool), register_tool(perfectionist))] at the crate root so non-dylint builds stay clean.
• [lints.rust] unexpected_cfgs.check-cfg in Cargo.toml declares the dylint_lib cfg.

Filed upstream issues

Tracked here because my GitHub scope did not include the perfectionist repo:

• perfectionist::single_letter_let_binding fires inside clap_derive's default_value_t expansion #410
• perfectionist::single_letter_closure_param's "trivial wrapper" classifier ignores macro-call bodies #411
• perfectionist::single_letter_closure_param default comparison_methods omits common third-party comparators like into_sorted_by #413
• perfectionist::macro_argument_binding's suggested fix breaks the debug-only contract of the debug_assert_* family #415
• perfectionist::macro_argument_binding flags name = value / name += value DSL matchers as non-trivial expressions #416
• perfectionist::macro_argument_binding treats the unit literal () as a non-trivial expression #417
• perfectionist::macro_argument_binding treats bare operator tokens (==, >, …) as non-trivial expressions #418
• perfectionist::macro_argument_binding late-pass anchors item-position macro violations at the crate root, breaking scoped #[expect] #419, closed as not reproducible on the current toolchain

Test plan

• TEST_SKIP='fs_errors cross_device_excludes_mount' FMT=true LINT=true BUILD=true TEST=true DOC=true DYLINT=true ./test.sh (the two skipped tests require root and FUSE/squashfs-tools respectively, per the harness's own skip hints).

https://claude.ai/code/session_01CoRidYHvni9nKNgxMPXmfQ

[github-actions]

Performance Regression Reports

commit: c54849b

There are no regressions.

[KSXGitHub]

Addressed in f792aa0. Per-comment status:

Thread	Status
r3230968898 — Display after Debug, drop "Standard traits" label	Done. Prefix reordered; all in-array labels dropped.
r3230984853 — labelled groupings not codebase-accurate	Done. Labels dropped along with the prefatory comment block.
r3230991752 — AsRef, Deref, Into desired order in fraction.rs	Done. New prefix puts reference wrappers before conversions, so the rule now produces this order automatically.
r3230999172 — #[expect] on ConversionError	Done. #[non_exhaustive] replaced with #[cfg_attr(dylint_lib = "perfectionist", expect(perfectionist::non_exhaustive_error, reason = "…"))].
r3231002016 — same for FromStrError	Done.
r3231007395 — Debug, Display, Error, Clone, Copy, PartialEq, Eq for hardlink_list::reflection::ConversionError	Done. New prefix produces this order automatically.
r3231012477 — SmartDefault next to Default	Done. SmartDefault added to the prefix immediately after Default.
r3231018048 — revert tests/_utils.rs since 50f4965 allows it	Done. link! / symlink! macros restored; link and symlink added to allow_extra.
r3231025988 — old CONTRIBUTING.md was inaccurate	Acknowledged. The derive-ordering paragraph and example are rewritten to match the new prefix.
r3231027513 — remove dylint.toml rambling (line 16)	Done.
r3231030637 / r3231032551	Skipped per your "Never mind".
r3231033714 — remove dylint.toml rambling (line 52)	Done.
r3231034889 — collapse allow_extra to one line	Done. Also collapsed comparison_methods for consistency.
r3231035935 — empty suggestion at line 67	Done.

Twenty derive lists across the codebase were reordered to match the new prefix. CI is green locally with TEST_SKIP='fs_errors cross_device_excludes_mount' FMT=true LINT=true BUILD=true TEST=true DOC=true DYLINT=true ./test.sh. Feel free to resolve the threads.

---

Generated by Claude Code

[Copilot]

Pull request overview

This pull request updates the repository’s Dylint setup to track the current perfectionist master (via a pinned revision) and applies collateral code/doc changes so the codebase complies with the newer lint set (derive ordering, single-letter name rules, and related cleanup).

Changes:

• Upgrade perfectionist in dylint.toml and add explicit lint configuration (derive_ordering, macro_argument_binding, single_letter_closure_param).
• Adjust Rust code to satisfy the new/stricter linting rules (derive ordering, identifier renames, Arc::clone, and removing an inappropriate derive_more::Error derive).
• Add build “plumbing” for Dylint-only cfg/tool registration and declare the dylint_lib cfg in Cargo.toml to avoid unexpected_cfgs noise.

Reviewed changes

Copilot reviewed 29 out of 29 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/cli_errors.rs	Updates expected stderr strings to raw string literals (escaping cleanup).
tests/_utils.rs	Renames a single-letter closure param to satisfy single-letter naming lint.
template/ai-instructions/shared.md	Removes a derive-order bullet from shared AI instructions template.
src/visualizer/tree.rs	Reorders derives to match configured derive_ordering.
src/visualizer/proportion_bar.rs	Reorders derives to match configured derive_ordering.
src/usage_md.rs	Renames a closure param to avoid single-letter naming lint.
src/reporter/progress_report.rs	Reorders derives (incl. Setters) per lint configuration.
src/reporter/progress_and_error_reporter.rs	Uses Arc::clone(&...) instead of .clone() for clarity.
src/reporter/error_report/text_report.rs	Switches expected string to raw literal (escaping cleanup).
src/os_string_display.rs	Reorders derive list to match configured derive_ordering.
src/lib.rs	Adds Dylint-only register_tool(perfectionist)/feature gating.
src/json_data/binary_version.rs	Reorders derives to match configured derive_ordering.
src/inode.rs	Reorders derives to match configured derive_ordering.
src/hardlink/hardlink_list/summary.rs	Reorders derives (incl. Setters) per lint configuration.
src/hardlink/hardlink_list.rs	Reorders derives to match configured derive_ordering.
src/device.rs	Reorders derives to match configured derive_ordering.
src/bytes_format/parsed_value.rs	Drops derive_more::Error from a non-error return value type.
src/args/threads.rs	Reorders derives to match configured derive_ordering.
src/args/fraction.rs	Reorders derives to match configured derive_ordering.
src/args/depth.rs	Reorders derives to match configured derive_ordering.
src/args.rs	Adds Dylint-only module-level allow for a proc-macro false positive; reorders derives.
src/app/overlapping_arguments/test_remove_overlapping_paths.rs	Renames trait method params to descriptive identifiers.
src/app/overlapping_arguments.rs	Renames trait method params to descriptive identifiers.
dylint.toml	Pins perfectionist by rev and adds lint configuration blocks.
CONTRIBUTING.md	Updates derive-ordering documentation to reflect lint enforcement/config.
CLAUDE.md	Removes derive-order bullet from instructions.
AGENTS.md	Removes derive-order bullet from instructions.
.github/copilot-instructions.md	Removes derive-order bullet from instructions.
Cargo.toml	Declares dylint_lib cfg in unexpected_cfgs check-cfg list.

Comments suppressed due to low confidence (2)

src/args/fraction.rs:21

• The PR description mentions adding #[non_exhaustive] to ConversionError to satisfy perfectionist::non_exhaustive_error, but this enum is still exhaustive. If you do enable that lint, annotate this enum (and update any exhaustive matches); otherwise update the PR description to match the actual behavior.

This issue also appears on line 44 of the same file.

/// Error that occurs when calling [`Fraction::new`].
#[derive(Debug, Display, Error, Clone, Copy, PartialEq, Eq)]
pub enum ConversionError {
    /// Provided value is greater than or equal to 1.
    #[display("greater than or equal to 1")]
    UpperBound,
    /// Provided value is less than 0.
    #[display("less than 0")]
    LowerBound,
}

src/args/fraction.rs:49

• The PR description mentions adding #[non_exhaustive] to FromStrError to satisfy perfectionist::non_exhaustive_error, but this enum is still exhaustive. If you do enable that lint, annotate this enum (and update any exhaustive matches); otherwise update the PR description to match the actual behavior.

/// Error that occurs when parsing a string as [`Fraction`].
#[derive(Debug, Display, Error, Clone, PartialEq, Eq)]
pub enum FromStrError {
    ParseFloatError(ParseFloatError),
    Conversion(ConversionError),
}