Member predicate CustomAbstractValueFromDefinition::getAPrototype

Gets an abstract value that represents a prototype object of this value.

We currently model three sources of prototypes:

• direct assignments to o.__proto__ are tracked;

• for an instance o of a function f, any value that can be shown to flow into f.prototype is considered a prototype object of o;

• for an instance of a class C, any instance of a function or class that can be shown to flow into the extends clause of C is considered a prototype object of o.

In all cases, purely local flow tracking is used to find prototype objects, so this predicate cannot be relied on to compute all possible prototype objects.