tests/cases/compiler/errorMessageOnObjectLiteralType.ts(5,3): error TS2339: Property 'getOwnPropertyNamess' does not exist on type '{ a: string; b: number; }'. tests/cases/compiler/errorMessageOnObjectLiteralType.ts(6,8): error TS2551: Property 'getOwnPropertyNamess' does not exist on type 'ObjectConstructor'. Did you mean 'getOwnPropertyNames'? ==== tests/cases/compiler/errorMessageOnObjectLiteralType.ts (2 errors) ==== var x: { a: string; b: number; }; x.getOwnPropertyNamess(); ~~~~~~~~~~~~~~~~~~~~ !!! error TS2339: Property 'getOwnPropertyNamess' does not exist on type '{ a: string; b: number; }'. Object.getOwnPropertyNamess(null); ~~~~~~~~~~~~~~~~~~~~ !!! error TS2551: Property 'getOwnPropertyNamess' does not exist on type 'ObjectConstructor'. Did you mean 'getOwnPropertyNames'? !!! related TS2728 /.ts/lib.es5.d.ts:181:5: 'getOwnPropertyNames' is declared here.