feature-envy doesn't take destructuring of own data into account.

[Nimelrian]

When destructuring the data of an object inside one of its methods, the feature-envy rule does not realize that the newly created variables actually belong to the object.

Example:

const foreign = {
    constant1: 5,
    constant2: 5,
    constant3: 5
};

class Foo {
    private ownStuff = {
        num1: 42,
        num2: 1337,
        num3: 1024
    };

    // Method "doStuff" uses "foreign" more than its own class "Foo". Extract or Move Method from "doStuff" into "foreign". (no-feature-envy)
    public doStuff(num: number) {
        const { num1, num2, num3, num4, num5, num6 } = this.ownStuff;
        return foreign.constant1 + foreign.constant2 + foreign.constant3 + num1 + num2 + num3;
    }

    // No error
    public doOtherStuff(num: number) {
        return (
            foreign.constant1 +
            foreign.constant2 +
            foreign.constant3 +
            this.ownStuff.num1 +
            this.ownStuff.num2 +
            this.ownStuff.num3
        );
    }
}

[Glavin001]

Pull Requests welcome!

Applicable files:

• https://github.com/Glavin001/tslint-clean-code/blob/master/src/tests/NoFeatureEnvyRuleTests.ts
• https://github.com/Glavin001/tslint-clean-code/blob/master/src/noFeatureEnvyRule.ts

Please let me know if you have any questions. 😃