fix(typia): validate intersected object unions

[samchon]

Intent

Fix #1590 by making the native transform validate intersected object unions without selecting an overlapping branch from one side of the intersection as if it proved the other side.

Changes

• Tighten object-union specialization so shared or overlapping structural fields are not used as unsafe discriminators.
• Keep safe shared literal discriminators usable with the Neighbor flag.
• Make metadata containment/intersection checks handle Map keys/values, tuple elements, tuple rest wrappers and rest tails, empty tuple targets, nested collection entries, template literals, wrapper/native names, and overlapping collection buckets precisely enough for union specialization.
• Share the runtime atomic-like native decision between metadata containment and native predicate generation, with BigInt explicitly excluded from that runtime-wrapper set.
• Add transform/runtime coverage for the original Party & PartyRoleInfo case across is, validate, assert, and direct typia.validate paths.
• Add focused Go regression tests for primitive-wrapper natives, collection buckets, native names, templates, tuple entries, tuple rest/empty targets, nested collection entries, map entries, object-valued shared fields, repeated tuple coverage, and neighbor discriminator behavior.
• Bump typia to 13.0.0-dev.20260605.11 because this PR changes native source shipped in the npm package.

Validation

• pnpm format
• git diff --check
• go test ./metadata/schema -run 'TestMetadataSchema(CoversNestedCollectionEntries|CoversTupleEntries|CoversMapEntries|CoversAtomicLikeNatives|IntersectsAtomicLikeNatives)$' -count=1 -v from packages/typia/test
• go test ./metadata/schema -run 'TestMetadataSchema(CoversTupleEntries|Covers|Intersects)' -count=1 -v from packages/typia/test
• go test ./helpers/predicator -run 'TestAtomicPredicator(RejectsNativeOverlaps|RecognizesPrimitiveNativeNames)$' -count=1 -v from packages/typia/test
• go test ./core/programmers/internal ./core/programmers/json ./core/programmers/iterate -count=1 from packages/typia/native
• go test ./core/schemas/metadata ./core/programmers/iterate -count=1 from packages/typia/native
• go test ./core/programmers/helpers -run 'TestUnionPredicator(SkipsAtomicLikeNativeFields|ChecksNeighborFlag|SkipsSharedTemplateFields)$' -count=1 -v from packages/typia/native
• go test ./core/programmers/helpers -run 'TestUnionPredicator(SkipsSharedObjectFields|SkipsSharedNativeNames|SkipsCollectionBucketFields|ChecksNeighborFlag)$' -count=1 -v from packages/typia/native
• go test ./cmd/ttsc-typia -run TestIntersectionUnionValidationTransform -count=1 -v from packages/typia/native
• pnpm test:go

Local Limitations

• Local pnpm test is blocked on Node v22.15.0 before this PR's tests run because local ttsc resolves typia/lib/transform to packages/typia/src/transform.ts, which this Node version cannot require directly. GitHub CI uses Node 24.x.
• Direct go test -tags typia_native_internal ./... from packages/typia/test is still blocked by existing package-layout/internal-import constraints outside this PR.

Remaining Gates

• Research Review Round 13 after commit 27cb467cf.
• GitHub CI after the latest push.

Fixes #1590.

[samchon]

Research Review Round 1 produced surviving proposals. Applied follow-up commit b805844 to split native-name metadata tests, add direct UnionPredicator coverage for shared native fields, harden the transform runtime fixture/import guards, and expand the valid/invalid intersection matrix. Local Go validation has been rerun after the follow-up.

[samchon]

Research Review Round 2 produced surviving proposals. Applied follow-up commit 19e4042 to mirror reserved-word handling in the shared transform runtime stub and remove #1590 from .wiki before final issue closure. Local validation was rerun after the follow-up: pnpm format, focused transform/metadata/UnionPredicator tests, pnpm test:go, diff checks, and .wiki no-match search.

[samchon]

Research Review Round 3 produced one surviving proposal. Applied follow-up commit 588e02f to rename the shared transform helper file to *_test.go so it is listed under TestGoFiles, not production GoFiles. Verified with go list, focused transform tests, UnionPredicator test, pnpm run format:go, pnpm test:go, diff checks, and .wiki no-match search.

[samchon]

Research Review Round 4 follow-up applied in ee7926abb:

• mirrored _validateReport path filtering/default-description behavior in the native transform test stub;
• kept transform_helpers_test.go test-only and verified it with go list -json ./cmd/ttsc-typia;
• added primitive-wrapper native overlap/coverage for String, Number, and Boolean against matching primitives/constants/template strings;
• added Set/Map bucket overlap and explicit Map key/value coverage;
• added focused metadata and UnionPredicator regression tests for those cases;
• corrected the PR body wording for the go test -tags typia_native_internal ./... limitation.

Local validation already passed before the push: pnpm format, pnpm run format:go, focused Go tests, pnpm test:go, full go test ./... -count=1 under both packages/typia/native and packages/typia/test, and .wiki grep for #1590.

[samchon]

Research Review Round 5 follow-up applied in 8a78fe660:

• added conservative template-vs-template intersection handling and metadata coverage;
• added array/tuple cross-bucket intersection handling and metadata/UnionPredicator coverage;
• added transform runtime cases for primitive-wrapper shared fields, empty Set, empty Map, and array/tuple branch selection;
• added negative template coverage checks for MetadataSchema_covers;
• corrected the PR body to remove the stale .wiki removal claim.

Focused validation after the patch passed: pnpm format, metadata schema tests, UnionPredicator tests, TestIntersectionUnionValidationTransform, and git diff --check.

[samchon]

Research Review Round 6 follow-up applied in 4f31af7fb:

• made template/string-literal intersections conservative so a literal like id-1 can no longer be selected as a discriminator against `id-${number}`;
• tightened the template intersection test to use an actually overlapping non-identical pair instead of pinning a disjoint pair;
• added direct template coverage tests for atomic string and exact template matches;
• strengthened UnionPredicator helper assertions to verify Index, Object, selected property ownership, and Neighbor flags.

Focused validation passed after the patch: pnpm format, metadata template tests, UnionPredicator shared-discriminator tests, TestIntersectionUnionValidationTransform, and git diff --check.

[samchon]

Round 7 follow-up pushed in 9a15ad5. I kept the transform runtime Date regression focused on rejection across is/validate/assert/direct validate, moved template-only negative coverage into the template containment test, added direct Neighbor=true discriminator coverage, added non-identical template overlap coverage, and fixed tuple element containment with tuple/map regression tests. Focused Go validations and pnpm format passed locally.

[samchon]

Round 8 follow-up pushed in 5e86978. I fixed nested collection coverage by removing the top-level-only array/tuple coverage gap with a visited-pair guard, added nested array/tuple regression tests, widened the transform test comment to match its runtime guard scope, and shared the runtime atomic-like native decision between metadata containment and Check_native while explicitly keeping BigInt out of that runtime-wrapper set. Validation passed locally: pnpm format, focused metadata/helper/transform Go tests, and pnpm test:go.

[samchon]

RRR 9 follow-up pushed as 2fff250d0.

Applied validated findings:

• Made MetadataSchema_covers keep strict root identity semantics while allowing nested same-pointer comparisons, and made the visited-pair guard path-local so one failed branch cannot leak into sibling candidates.
• Split runtime atomic/native filtering from schema primitive routing. Runtime validation/stringify now suppresses only actual Boolean/Number/String object-wrapper overlaps and leaves bigint behavior intact; schema-side routing still treats BigInt as an atomic-like native where needed.
• Reused the canonical MetadataSchema_atomicLikeNative mapping in native predicate generation instead of lowering arbitrary native names at the callsite.
• Added invalid right-branch runtime cases for shared Date, Uint8Array, primitive-wrapper, Set, Map, and array/tuple fields.
• Added focused regressions for duplicate nested array candidates, reused tuple element pointers, runtime BigInt preservation, and case-insensitive runtime predicate comparison.

Local validation after the push:

• pnpm format
• git diff --check
• go test ./cmd/ttsc-typia -run TestIntersectionUnionValidationTransform -count=1 -v
• go test ./helpers/predicator -run TestAtomicPredicator(RejectsNativeOverlaps|RecognizesPrimitiveNativeNames)$ -count=1 -v
• go test ./core/programmers/internal ./core/programmers/json ./core/programmers/iterate -count=1
• pnpm test:go

Next gate: RRR 10 on 2fff250d0, then latest GitHub CI.

[samchon]

RRR 10 follow-up pushed as 570def449.

Applied validated findings:

• Fixed repeated-extra tuple containment indexing in MetadataSchema_covers; the old i-len(target) index could panic when the source tuple had more than one repeated extra element.
• Added a tuple regression for multiple repeated extra elements.
• Added UnionPredicator coverage proving shared object-valued properties are not selected as discriminators.
• Tightened shared Set, Map, and array/tuple runtime invalid cases so the value is left-shaped while the right branch is selected, proving the right branch still validates the shared property.

Rejected finding:

• Plain gofmt -l is not the repository formatter gate here. pnpm format / pnpm run format:go intentionally run gofmt and then convert Go tabs to two spaces; this was rerun and passed.

Local validation after the push:

• pnpm format
• git diff --check
• go test ./metadata/schema -run TestMetadataSchemaCoversTupleEntries -count=1 -v
• go test ./core/programmers/helpers -run TestUnionPredicator(SkipsSharedObjectFields|SkipsSharedNativeNames|SkipsCollectionBucketFields|ChecksNeighborFlag)$ -count=1 -v
• go test ./cmd/ttsc-typia -run TestIntersectionUnionValidationTransform -count=1 -v
• pnpm test:go

Next gate: RRR 11 on 570def449, then latest GitHub CI.

[samchon]

RRR 11 follow-up pushed as 6c6545e03.

Applied validated findings:

• Added isParty(invalidOtherMissingDetail) negative coverage so the original invalid other branch is checked through createIs as well as validate, direct typia.validate, and assert.
• Closed MetadataSchema_covers fallthroughs for empty tuple targets and target Rest wrappers.
• Added tuple coverage for empty targets, rest-only source tuples, mismatched rest targets, compatible rest targets, and Rest targets that also carry another bucket.

Rejected finding:

• Plain gofmt -l remains rejected as a standalone gate because repo formatting is pnpm format / pnpm run format:go, which intentionally applies the local Go formatting convention after gofmt.

Local validation after the push:

• pnpm format
• git diff --check
• go test ./metadata/schema -run TestMetadataSchema(CoversTupleEntries|Covers|Intersects) -count=1 -v
• go test ./cmd/ttsc-typia -run TestIntersectionUnionValidationTransform -count=1 -v
• pnpm test:go

Next gate: RRR 12 on 6c6545e03, then latest GitHub CI.

[samchon]

RRR 12 follow-up pushed as 27cb467cf.

Applied validated findings:

• Added BigInt primitive coverage for createIs and createAssert, alongside the existing createValidate checks. The coverage intentionally asserts primitive 1n only, not Object(1n).
• Fixed source trailing-rest tuple coverage so tuples like [string, ...number[]] can cover fixed target tails such as [head, 1, 2].
• Added tuple coverage for source rest-only tuples covering non-empty fixed targets and for mismatched source rest tails.

Local validation after the push:

• pnpm format
• git diff --check
• go test ./metadata/schema -run TestMetadataSchema(CoversTupleEntries|Covers|Intersects) -count=1 -v
• go test ./cmd/ttsc-typia -run TestIntersectionUnionValidationTransform -count=1 -v
• go test ./core/programmers/internal ./core/programmers/json ./core/programmers/iterate -count=1
• go test ./helpers/predicator -run TestAtomicPredicator(RejectsNativeOverlaps|RecognizesPrimitiveNativeNames)$ -count=1 -v
• pnpm test:go

Next gate: RRR 13 on 27cb467cf, then latest GitHub CI.