classLooksLike Available since v0.9

Determines if a target class "looks like" the provided class "blueprint".

• Arguments
• Class Blueprint
• Recursive

Arguments

classLooksLike() accepts the following arguments:

• target: object - the target class object.
• blueprint: ClassBlueprint - a blueprint that defines the expected members of a class (see Class Blueprint for details.).

import { classLooksLike } from '@aedart/support/reflections';

class A {}

class B {
    foo() {}
}

const blueprint = { members: [ 'foo' ] };

classLooksLike(A, blueprint); // false
classLooksLike(B, blueprint); // true

Class Blueprint

The class "blueprint" is an object that defines the expected members (property keys) of a target class. All defined members must exist in target class' prototype, before the classLooksLike() returns true.

You can specify either or both of the following properties in a class blueprint object:

• members: PropertyKey[] - (optional) Properties or methods expected to exist in class' prototype.
• staticMembers: PropertyKey[] - (optional) Properties or methods expected to exist in class as static members.

Note: If you do not specify either members or staticMembers, then a TypeError is thrown.

class A {
    foo() {}

    bar() {}
}

class B {
    foo() {}
    
    static bar() {}
}

const blueprint = { members: [ 'foo' ], staticMembers: [ 'bar' ] };

classLooksLike(A, blueprint); // false
classLooksLike(B, blueprint); // true

Recursive

classLooksLike() traverses target class' prototype chain. This means that you can compare a subclass against a blueprint and inherited members will automatically be included in the check.

class A {
    foo() {}
}

class B extends A {
    bar() {}
}

const blueprint = { members: [ 'foo', 'bar' ]};

classLooksLike(A, blueprint); // false
classLooksLike(B, blueprint); // true