[FNDEVVE]

Problem

no-manual-tagged-construction incorrectly flags literal _tag objects in Match patterns as value construction when nested inside objects/arrays or used with multi-predicate helpers like Match.whenAnd:

Match.whenAnd(
  HttpClientError.isHttpClientError,
  { reason: { _tag: "StatusCodeError", response: { status: 429 } } },
  () => true,
)

Previously, isMatchPatternObject only checked node.parent directly for Match.when or Match.not, which failed for nested containers and missed whenAnd / whenOr.

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Solution

Walk outward from the _tag ObjectExpression through nested pattern containers (properties within ObjectExpression, ArrayExpression, and parentheses) to the enclosing Match call, ensuring the containing argument is a pattern/predicate and not a handler:

flowchart TD
    Node["ObjectExpression with _tag"] --> Loop{"Walk Up Containers"}
    Loop -->|"Property.value in Object"| Obj["Parent ObjectExpression"]
    Loop -->|"Element in Array"| Arr["Parent ArrayExpression"]
    Loop -->|"Expression in Parentheses"| Paren["Parent ParenthesizedExpression"]
    Obj --> Loop
    Arr --> Loop
    Paren --> Loop
    Loop -->|"Boundary / Enclosing Call"| Call{"Enclosing Call"}
    Call -->|"Match.when / not / whenAnd / whenOr"| CheckArg{"Argument Position"}
    Call -->|"Other function or boundary"| Flag["❌ Flag as manualConstruction"]
    CheckArg -->|"Pattern argument (index < last)"| Pass["✅ Allowed pattern"]
    CheckArg -->|"Handler argument (last argument)"| Flag

Loading

- node.parent === Match.when | Match.not (direct only)
+ while (parent in [Property.value, ArrayExpression, ParenthesizedExpression])
+   current = parent
+ if (current.parent in [Match.when, Match.not, Match.whenAnd, Match.whenOr])
+   allow only if current is a pattern argument (not the handler)

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Changes

• Updated isMatchPatternObject in src/effect/shared/tagged-values.ts to support outward container traversal.
• Covered Match.when, Match.not, Match.whenAnd, and Match.whenOr (supporting both Match.* and Effect.Match.*).
• Verified handlers (arrow returns, block returns, arrays, handler objects) and helper calls inside patterns remain strictly rejected.
• Added exhaustive RuleTester test coverage in src/effect/rules/no-manual-tagged-construction.test.ts.
• Synced skill assets with pnpm sync:skill-assets.