Cannot override method in subclass when superclass instance type is a mapped type

TypeScript Version: 3.1.1

Search Terms:
defines instance member property

Code

class A {
    foo(): void {};
    bar: number;
}

class B extends (A as { new(): Pick<A, Exclude<keyof A, "foo">> & Pick<A, "foo"> }) {
    // (1)
    foo(): void {
        super.foo();
    }
    baz: number;
}

Expected behavior:
Compiles successfully

Actual behavior:

Error at (1): [ts] Class 'Pick<A, "bar"> & Pick<A, "foo">' defines instance member property 'foo', but extended class 'B' defines it as instance member function.

Playground Link: http://www.typescriptlang.org/play/index.html#src=class%20A%20%7B%0D%0A%20%20%20%20foo()%3A%20void%20%7B%7D%3B%0D%0A%20%20%20%20bar%3A%20number%3B%0D%0A%7D%0D%0A%0D%0Aclass%20B%20extends%20(A%20as%20%7B%20new()%3A%20Pick%3CA%2C%20Exclude%3Ckeyof%20A%2C%20%22foo%22%3E%3E%20%26%20Pick%3CA%2C%20%22foo%22%3E%20%7D)%20%7B%0D%0A%20%20%20%20foo()%3A%20void%20%7B%0D%0A%20%20%20%20%20%20%20%20super.foo()%3B%0D%0A%20%20%20%20%7D%0D%0A%20%20%20%20baz%3A%20number%3B%0D%0A%7D

A more realistic example of this is when using https://github.com/bterlson/strict-event-emitter-types along with subclassing a superclass with overridable methods:

import StrictEventEmitter from "strict-event-emitter-types";
import * as inspector from "inspector";

interface SessionEvents {
  "Runtime.executionContextCreated": (message: inspector.InspectorNotification<Runtime.ExecutionContextCreatedEventDataType>) => void
}
type StrictSession = StrictEventEmitter<inspector.Session, SessionEvents>;
class CustomSession extends (inspector.Session as { new (): StrictSession }) {
  connect() { // error here
    super.connect();
  }
}

Start with the TypeScript code sample and Playground link to reproduce the diagnostic involving Pick, Exclude, and the subclass override. Trace how the compiler compares the mapped superclass member with B.foo, then add coverage for the example and confirm the valid override compiles without an error.