# Feature Envy

> A defect in which one module mostly works on another module's data instead of its own.

Record: `architecture:feature-envy`
Kind: anti-pattern
Layer: [Enforcement Core](https://banes-lab.com/records/layer/enforcement-core.md)
Severity: discouraged
Scope: modularity, contract_compatibility
Canonical: https://banes-lab.com/ontology#architecture-feature-envy

Listed in [Architecture principles](https://banes-lab.com/api/records/architecture.md), after [Divergent Change](https://banes-lab.com/records/architecture/divergent-change.md) and before [Inappropriate Intimacy](https://banes-lab.com/records/architecture/inappropriate-intimacy.md).

## Repair

- Refactored by: move_method, encapsulate_state, add_domain_behavior, introduce_service_boundary
- Detected by: many_getters_from_other_object, logic_using_foreign_fields, domain_rule_outside_owner
- Violated by: Let one module repeatedly inspect or manipulate another module’s data instead of moving behavior to the data owner.
- Measured by: foreign field accesses per method
- Enforced by: coupling analysis in lint, [design review](https://banes-lab.com/records/architecture/design-review.md)

## Severity

- [discouraged](https://banes-lab.com/records/vocabulary/severity-discouraged.md)

## Category

- [Anti-patterns](https://banes-lab.com/records/architecture-category/anti-patterns.md)

## Force

- [Contract compatibility](https://banes-lab.com/records/force/contract-compatibility.md)
- [Modularity](https://banes-lab.com/records/force/modularity.md)

## Negated by

- [Encapsulation](https://banes-lab.com/records/architecture/encapsulation.md)

## Linked from

- [Anti-patterns](https://banes-lab.com/ontology/principles/architecture-category-anti-patterns.md)
- [Core Modular Design](https://banes-lab.com/ontology/principles/architecture-category-core-modular-design.md)
- [Core Modular Design](https://banes-lab.com/ontology/lexicon/lexicon-category-core-modular-design.md)
- [Severity levels](https://banes-lab.com/ontology/schema/the-vocabulary-severity.md)
- [The forces](https://banes-lab.com/ontology/schema/the-forces.md)