HasProperty TypeScript utility for checking whether an object has a property

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hasProperty.ts

// actual type:
type HasProperty<
  T,
  Property,
  MappedT = AllDefinedAsTrue<T> & AllUndefinedAsFalse & Padding,
> = MappedT[keyof MappedT & Property];

// usage:
type TrueExample = HasProperty<{abc: number}, 'abc'>;
type TrueExample2 = HasProperty<{abc: number, def: number}, 'def'>;
type FalseExample = HasProperty<{}, 'abc'>;
type FalseExample2 = HasProperty<{xyz: number}, 'abc'>;
type TrueExample3 = HasProperty<Function, 'apply'>;

// tests:
const ex1: TrueExample = '1';
const ex2: TrueExample2 = '1';
const ex3: FalseExample = '0';
const ex4: FalseExample2 = '0';
const ex5: TrueExample3 = '1';

// helpers:
type AllDefinedAsTrue<T> = {
  [P in keyof T]: '1';
};
type AllUndefinedAsFalse = {
  [any: number]: '0';
};
// "padding" is needed,
// otherwise objects with one or zero props return 'any'
// for some reason
type Padding = {
  '____________': '0';
  '_____________': '0';
};