📦🔧：align validators with runtime checks

[DerekNonGeneric]

Requested by DerekNonGeneric · project thread

Review only. Do not merge. This replays the already-merged #106 (commit f9148e8 against its parent) so CodeRabbit can review it, because it hit its rate limit when #106 was open and it refuses to review closed PRs. Findings will be fixed in a separate PR against main, and this PR will be closed.

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Summary by CodeRabbit

• Breaking Changes
  • Equality checks no longer narrow values to the expected type. Array and array-like checks now narrow elements to unknown, and iterator checks return a boolean without narrowing.
  • Interface validation now requires validators that fully cover supported object properties, including optional properties.
• Type Improvements
  • Valid-date and well-formed-string checks now narrow to dedicated refined types.
  • map reports its one-level-flattened result type and omits nullish results.
• Tests
  • Added compile-time and runtime coverage for updated validation and mapping behavior.

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📝 Walkthrough

Walkthrough

Several packages update guard and validator types to avoid claiming types that runtime checks do not establish. The changes also add tagged types for valid dates and well-formed strings, tighten hasInterface constraints, and update array helper result types.

Changes

Validation type boundaries

Layer / File(s)	Summary
Equality validators packages/assert/src/guards/is-deep-equal-to.ts, packages/assert/src/guards/is-equal-to.ts, packages/assert/src/guards/is-identical-to.ts, packages/assert/test/guards/equality-types.ts	The three equality helpers now return Validator values instead of type predicates. Tests check that equality does not narrow values to the expected type.
Array checks and mapping packages/util-array/src/guards/is-array-like.ts, packages/util-array/src/helpers/map.ts, packages/util-array/test/guards/is-array-like.ts, packages/util-array/test/helpers/map.ts, packages/util-core/src/guards/is-array.ts, packages/util-core/test/guards/is-array.ts	isArrayLike and isArray narrow to containers with unknown elements. map declares one-level-flattened, non-nullish results. Tests check these types and the existing flattening behavior.
Interface validation constraints packages/util-core/src/guards/has-interface.ts, packages/util-core/test/guards/has-interface.ts	hasInterface accepts supported object types, requires validators for complete property types, and narrows successful values to Required<T> & object. Runtime checks include inherited and symbol-keyed validators.
Refined and shallow guard results packages/util-date/src/guards/is-valid-date.ts, packages/util-date/test/guards/is-valid-date.ts, packages/util-string/src/guards/is-well-formed-string.ts, packages/util-string/test/guards/is-well-formed-string.ts, packages/util-types/src/guards/is-iterator.ts, packages/util-types/test/guards/is-iterator.ts, .changeset/sound-validation-types.md	Date and string guards narrow successful checks to tagged types. isIterator returns a boolean without narrowing. Tests check the type and runtime behavior, and the changeset marks six packages for major releases.

Priority: ⬇️ Low

Estimated code review effort: 3 (Moderate) | ~25 minutes

Change: Bug fix

Merge Risk: 🟡 Moderate · up to f9148

A value can pass interface validation without satisfying a declared constructor property. Fix that validation gap before merging; this PR is also explicitly designated not to be merged.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 52.63% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 19 functions across 18 files. (1 skipped:…	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the main change: aligning validator type declarations with the behavior established by runtime checks. It is concise and related to the changeset.

Full details: Docstring Coverage

Explanation

Docstring coverage is 52.63% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 19 functions across 18 files. (1 skipped: 1 unsupported.)

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[DerekNonGeneric]

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Generated by Claude Code

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Actionable comments posted: 1

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Inline comments:
Review comments at @packages/util-core/src/guards/has-interface.ts:
- Line 98: Update the key filtering in hasInterface so it skips the prototype’s
default constructor but retains an explicitly declared constructor key when a
validator is supplied; add a regression test confirming `{}` does not pass for a
required numeric constructor property.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Essentials

Run ID: 2d5cfc41-51bc-4930-b023-834adc57f7e6

📥 Commits

Reviewing files that changed from the base of the PR and between 3fea509 and f9148e8.

📒 Files selected for processing (19)

• .changeset/sound-validation-types.md
• packages/assert/src/guards/is-deep-equal-to.ts
• packages/assert/src/guards/is-equal-to.ts
• packages/assert/src/guards/is-identical-to.ts
• packages/assert/test/guards/equality-types.ts
• packages/util-array/src/guards/is-array-like.ts
• packages/util-array/src/helpers/map.ts
• packages/util-array/test/guards/is-array-like.ts
• packages/util-array/test/helpers/map.ts
• packages/util-core/src/guards/has-interface.ts
• packages/util-core/src/guards/is-array.ts
• packages/util-core/test/guards/has-interface.ts
• packages/util-core/test/guards/is-array.ts
• packages/util-date/src/guards/is-valid-date.ts
• packages/util-date/test/guards/is-valid-date.ts
• packages/util-string/src/guards/is-well-formed-string.ts
• packages/util-string/test/guards/is-well-formed-string.ts
• packages/util-types/src/guards/is-iterator.ts
• packages/util-types/test/guards/is-iterator.ts

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