Feature Envy

Symptom

A method on class A reaches deeply into class B's data via getters, then computes something B should compute.

Goal

Methods live with the data they care about — B owns the logic over B's fields.

Smellier version

class Order {
  totalWeight() {
    return this.items.reduce((s, i) => s + i.unitWeight * i.qty, 0);
  }
}

Fresher version

class Item  { weight()      { return this.unitWeight * this.qty; } }
class Order { totalWeight() { return this.items.reduce((s, i) => s + i.weight(), 0); } }

Savings

Encapsulation tightens, getters can shrink or disappear, and the method's name clarifies once it's on the right class.

Note

Domain logic lives where it's least expected; B's internals leak through public surfaces just to support A's method.