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tests/cases/conformance/types/thisType/thisTypeInFunctions.ts(118,29): error TS2339: Property 'n' does not exist on type 'typeof globalThis'.
tests/cases/conformance/types/thisType/thisTypeInFunctions.ts(119,32): error TS2339: Property 'n' does not exist on type 'typeof globalThis'.
tests/cases/conformance/types/thisType/thisTypeInFunctions.ts(120,36): error TS2339: Property 'n' does not exist on type 'typeof globalThis'.
==== tests/cases/conformance/types/thisType/thisTypeInFunctions.ts (3 errors) ====
// body checking
class B {
n: number;
}
class C {
n: number;
explicitThis(this: this, m: number): number {
return this.n + m;
}
explicitC(this: C, m: number): number {
return this.n + m;
}
explicitProperty(this: {n: number}, m: number): number {
return this.n + m;
}
explicitVoid(this: void, m: number): number {
return m + 1;
}
}
class D extends C { }
interface I {
a: number;
explicitVoid1(this: void): number;
explicitVoid2(this: void): number;
explicitStructural(this: {a: number}): number;
explicitInterface(this: I): number;
explicitThis(this: this): number;
}
function explicitStructural(this: { y: number }, x: number): number {
return x + this.y;
}
function justThis(this: { y: number }): number {
return this.y;
}
function implicitThis(n: number): number {
return this.m + n + 12;
}
let impl: I = {
a: 12,
explicitVoid2: () => this.a, // ok, this: any because it refers to some outer object (window?)
explicitVoid1() { return 12; },
explicitStructural() {
return this.a;
},
explicitInterface() {
return this.a;
},
explicitThis() {
return this.a;
},
}
impl.explicitVoid1 = function () { return 12; };
impl.explicitVoid2 = () => 12;
impl.explicitStructural = function() { return this.a; };
impl.explicitInterface = function() { return this.a; };
impl.explicitStructural = () => 12;
impl.explicitInterface = () => 12;
impl.explicitThis = function () { return this.a; };
// parameter checking
let ok: {y: number, f: (this: { y: number }, x: number) => number} = { y: 12, f: explicitStructural };
let implicitAnyOk: {notSpecified: number, f: (x: number) => number} = { notSpecified: 12, f: implicitThis };
ok.f(13);
implicitThis(12);
implicitAnyOk.f(12);
let c = new C();
let d = new D();
let ripped = c.explicitC;
c.explicitC(12);
c.explicitProperty(12);
c.explicitThis(12);
d.explicitC(12);
d.explicitProperty(12);
d.explicitThis(12);
let reconstructed: {
n: number,
explicitThis(this: C, m: number): number, // note: this: this is not allowed in an object literal type.
explicitC(this: C, m: number): number,
explicitProperty: (this: {n : number}, m: number) => number,
explicitVoid(this: void, m: number): number,
} = {
n: 12,
explicitThis: c.explicitThis,
explicitC: c.explicitC,
explicitProperty: c.explicitProperty,
explicitVoid: c.explicitVoid
};
reconstructed.explicitThis(10);
reconstructed.explicitProperty(11);
let explicitVoid = reconstructed.explicitVoid;
explicitVoid(12);
// assignment checking
let unboundToSpecified: (this: { y: number }, x: number) => number = x => x + this.y; // ok, this:any
let specifiedToSpecified: (this: {y: number}, x: number) => number = explicitStructural;
let anyToSpecified: (this: { y: number }, x: number) => number = function(x: number): number { return x + 12; };
let unspecifiedLambda: (x: number) => number = x => x + 12;
let specifiedLambda: (this: void, x: number) => number = x => x + 12;
let unspecifiedLambdaToSpecified: (this: {y: number}, x: number) => number = unspecifiedLambda;
let specifiedLambdaToSpecified: (this: {y: number}, x: number) => number = specifiedLambda;
let explicitCFunction: (this: C, m: number) => number;
let explicitPropertyFunction: (this: {n: number}, m: number) => number;
c.explicitC = explicitCFunction;
c.explicitC = function(this: C, m: number) { return this.n + m };
c.explicitProperty = explicitPropertyFunction;
c.explicitProperty = function(this: {n: number}, m: number) { return this.n + m };
c.explicitProperty = reconstructed.explicitProperty;
// lambdas are assignable to anything
c.explicitC = m => m;
c.explicitThis = m => m;
c.explicitProperty = m => m;
// this inside lambdas refer to outer scope
// the outer-scoped lambda at top-level is still just `any`
c.explicitC = m => m + this.n;
~
!!! error TS2339: Property 'n' does not exist on type 'typeof globalThis'.
c.explicitThis = m => m + this.n;
~
!!! error TS2339: Property 'n' does not exist on type 'typeof globalThis'.
c.explicitProperty = m => m + this.n;
~
!!! error TS2339: Property 'n' does not exist on type 'typeof globalThis'.
//NOTE: this=C here, I guess?
c.explicitThis = explicitCFunction;
c.explicitThis = function(this: C, m: number) { return this.n + m };
// this:any compatibility
c.explicitC = function(m) { return this.n + m };
c.explicitProperty = function(m) { return this.n + m };
c.explicitThis = function(m) { return this.n + m };
// this: contextual typing
c.explicitThis = function(this, m) { return this.n + m };
// this: superclass compatibility
c.explicitC = function(this: B, m: number) { return this.n + m };
// this:void compatibility
c.explicitVoid = n => n;
// class-based assignability
class Base1 {
x: number;
public polymorphic(this: this): number { return this.x; }
explicit(this: Base1): number { return this.x; }
static explicitStatic(this: typeof Base1): number { return this.y; }
static y: number;
}
class Derived1 extends Base1 {
y: number
}
class Base2 {
y: number
polymorphic(this: this): number { return this.y; }
explicit(this: Base1): number { return this.x; }
}
class Derived2 extends Base2 {
x: number
}
let b1 = new Base1();
let b2 = new Base2();
let d1 = new Derived1();
let d2 = new Derived2();
d2.polymorphic = d1.polymorphic // ok, 'x' and 'y' in { x, y }
d1.polymorphic = d2.polymorphic // ok, 'x' and 'y' in { x, y }
// bivariance-allowed cases
d1.polymorphic = b2.polymorphic // ok, 'y' in D: { x, y }
d2.polymorphic = d1.explicit // ok, 'y' in { x, y }
b1.polymorphic = d2.polymorphic // ok, 'x' and 'y' not in Base1: { x }
b1.explicit = d2.polymorphic // ok, 'x' and 'y' not in Base1: { x }
////// use this-type for construction with new ////
function InterfaceThis(this: I) {
this.a = 12;
}
function LiteralTypeThis(this: {x: string}) {
this.x = "ok";
}
function AnyThis(this: any) {
this.x = "ok";
}
let interfaceThis = new InterfaceThis();
let literalTypeThis = new LiteralTypeThis();
let anyThis = new AnyThis();
//// type parameter inference ////
declare var f: {
(this: void, x: number): number,
call<U>(this: (...argArray: any[]) => U, ...argArray: any[]): U;
};
let n: number = f.call(12);
function missingTypeIsImplicitAny(this, a: number) { return this.anything + a; }
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