tests: #806 — systematic harness for class-extends-factory / mixin patterns#822
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proggeramlug wants to merge 2 commits into
Open
tests: #806 — systematic harness for class-extends-factory / mixin patterns#822proggeramlug wants to merge 2 commits into
proggeramlug wants to merge 2 commits into
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…tterns
`class X extends Fn(...)<...>` had zero systematic coverage. This harness
covers eight independent sub-cases, each printing a stable `section:
result` line so parity diffs pin exactly which sub-case regressed:
1. Bare factory — `class X extends makeBare()`.
2. Parameterized factory — `class X extends tagged("name", schema)`.
3. Captured-factory generic — `class X extends makeNamed<T>("...")`.
4. Chained mixins — `class X extends WithA(WithB(WithC(Base)))`.
5. Mixin with super-arg forwarding.
6. Factory with static method.
7. Effect-shape double-call — `class X extends TaggedError<X>()("tag", schema)`.
8. Parameterized mixin factory — `ParamMixin<T>(seed)(Base)`.
Verified against `node --experimental-strip-types` on macOS; baseline
prints 22 stable lines. Perry currently passes sub-cases 2, 3, and the
captured Effect shape (post-#740) but surfaces two real gaps:
- **Bare factory** — `bare.kind: undefined` instead of `bare.kind: bare`.
The base class's field initializer is dropped when the parent is a
factory-returned class expression.
- **Chained mixins** — `TypeError: value is not a function` thrown
before construction; the layered `WithA(WithB(WithC(...)))` shape
doesn't resolve through the mixin chain.
Both are linked to the #321 Effect umbrella and added to
`known_failures.json` so this PR doesn't break the parity gate. Each
sub-case flips to PASS independently as the underlying lowering work
lands.
This was referenced May 16, 2026
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Summary
New
test-files/test_harness_class_mixins.tscovers eight independent sub-cases ofclass X extends Fn(...)<...>, each emitting a stablesection: resultline so parity diffs pin exactly which sub-case regressed:class X extends makeBare()class X extends tagged(\"name\", schema)class X extends makeNamed<T>(\"...\")class X extends WithA(WithB(WithC(Base)))class X extends TaggedError<X>()(\"tag\", schema)What the harness surfaces today
Verified against
node --experimental-strip-typeson macOS (baseline prints 22 stable lines). Perry passes the parameterized-factory, captured-factory generic, and Effect double-call (post-#740) sub-cases — but the harness exposes two real gaps:bare.kind: undefinedvs Node'sbare.kind: bare. Base class's field initializer dropped when the parent is a factory-returned class expression.TypeError: value is not a functionat construction; the layeredWithA(WithB(WithC(Base)))shape doesn't resolve.Both are linked to the #321 Effect umbrella. The harness is added to
known_failures.jsonso this PR doesn't trip the parity gate; each sub-case flips to PASS independently as the underlying work lands.Test plan
node --experimental-strip-types test-files/test_harness_class_mixins.tsprints 22 lines, all sub-cases../target/release/perry test-files/test_harness_class_mixins.ts -o /tmp/harness && /tmp/harnessexits non-zero on the chained-mixin TypeError — diff vs Node pins the two gap locations cleanly.known_failures.jsonentry references tests: harness for dynamic class extension / mixins #806 + Tracking: Effect framework end-to-end compat (post-#309 / #310) #321 so the parity gate stays green.Closes #806.