inp

Inp Rules (inp)

The inp category contains static analysis rules for code quality, architectural constraints, and design system governance.

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Category Rule Index

Rule ID	Severity	Summary	Full Specification	Status
inp.context-re-render-cascade	WARN	Passing an unmemoized inline object literal to Context.Provider value triggers cascading re-renders across all consumers	inp.context-re-render-cascade	enabled
inp.expensive-render-computation	WARN	Expensive data transformations (chained .filter() and .sort()) execute synchronously in the render path without useMemo	inp.expensive-render-computation	enabled
inp.expensive-style-mutation	WARN	Continuous interaction handler imperatively mutates high-cost paint-sensitive style properties (boxShadow, filter, etc.)	inp.expensive-style-mutation	enabled
inp.heavy-event-handler	WARN	Interactive event handler executes heavy synchronous operations (JSON.parse, Array.sort) without cooperative yields	inp.heavy-event-handler	enabled
inp.hydration-contention	WARN	Concurrently hydrating multiple Astro client:load islands saturates the main thread and spikes input delay	inp.hydration-contention	enabled
inp.hydration-heavy-island	WARN	Client island wraps excessive static DOM subtree forcing heavy virtual DOM reconciliation on the client	inp.hydration-heavy-island	enabled
inp.large-interaction-layout-scope	WARN	Interactive overlay or drawer element lacks layout containment or native dialog isolation, triggering document-wide reflow on toggle	inp.large-interaction-layout-scope	enabled
inp.layout-thrashing	ERROR	Sequential DOM style mutation followed by layout geometry reading triggers forced synchronous reflow	inp.layout-thrashing	enabled
inp.missing-start-transition	INFO	Secondary non-urgent state update inside interactive handler should be wrapped in startTransition to prevent input lag	inp.missing-start-transition	enabled
inp.missing-touch-action	WARN	Interactive element with custom pointer or touch gesture handlers lacks an explicit touch-action CSS policy	inp.missing-touch-action	enabled
inp.render-blocking-script	WARN	External script element without defer, async, or type="module" synchronously blocks rendering and input responsiveness	inp.render-blocking-script	enabled
inp.repeated-state-update	WARN	Repeated state updater calls inside loops breaking automatic batching trigger cascading re-renders	inp.repeated-state-update	enabled
inp.sync-layout-effect	WARN	Synchronous non-geometrical computation in useLayoutEffect blocks browser paint and inflates presentation delay	inp.sync-layout-effect	enabled
inp.unbounded-collection-render	WARN	Scrollable collection container renders unbounded dynamic data via .map() without window virtualization or pagination limits	inp.unbounded-collection-render	enabled
inp.unbounded-effect-deps	ERROR	Lifecycle hook useEffect/useLayoutEffect is missing a dependency array, triggering unbounded re-executions on every render	inp.unbounded-effect-deps	enabled
inp.unyielded-long-task	WARN	Long task processing large arrays without cooperative scheduling yields stalls main-thread responsiveness	inp.unyielded-long-task	enabled

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How the Inp Analysis Pipeline Works

The inp engine applies static analysis checks against component source code:

flowchart LR
    TargetFiles["Target Files (*.astro, *.tsx)"] --> Parser["Leaf IR AST Parser"]
    Parser --> Engine["Rule Evaluator Engine"]
    Engine --> Check{"Evaluate Invariant"}
    Check -- "Compliant" --> Safe["Pass"]
    Check -- "Violation" --> Diag["Diagnostic: inp.*"]

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Pipeline Flow:

1. AST Node Traversal: Scans target template files into normalized intermediate representation.
2. Invariant Assertion: Validates structural and semantic invariants.
3. Diagnostic Reporting: Emits structured diagnostics for non-compliant patterns.

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How Inp Tests Work (Verification Harness)

All rules in inp are verified using the canonical 1-SSOT Tri-Corpus (tests/correctness/inp.*/) encompassing Positive (P1-P5), Negative (N1-N5), and Adversarial (A1-A7) fixture matrices.