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//// [privateNameInInExpression.ts]
class Foo {
#field = 1;
static #staticField = 2;
#method() {}
static #staticMethod() {}
goodRhs(v: any) {
const a = #field in v;
const b = #field in v.p1.p2;
const c = #field in (v as {});
const d = #field in (v as Foo);
const e = #field in (v as never);
for (let f in #field in v as any) { /**/ } // unlikely but valid
}
badRhs(v: any) {
const a = #field in (v as unknown); // Bad - RHS of in must be object type or any
const b = #fiel in v; // Bad - typo in privateID
const c = (#field) in v; // Bad - privateID is not an expression on its own
for (#field in v) { /**/ } // Bad - 'in' not allowed
for (let d in #field in v) { /**/ } // Bad - rhs of in should be a object/any
}
whitespace(v: any) {
const a = v && /*0*/#field/*1*/
/*2*/in/*3*/
/*4*/v/*5*/
}
flow(u: unknown, n: never, fb: Foo | Bar, fs: FooSub, b: Bar, fsb: FooSub | Bar, fsfb: Foo | FooSub | Bar) {
if (typeof u === 'object') {
if (#field in n) {
n; // good n is never
}
if (#field in u) {
u; // good u is Foo
} else {
u; // good u is object | null
}
if (u !== null) {
if (#field in u) {
u; // good u is Foo
} else {
u; // good u is object
}
if (#method in u) {
u; // good u is Foo
}
if (#staticField in u) {
u; // good u is typeof Foo
}
if (#staticMethod in u) {
u; // good u is typeof Foo
}
}
}
if (#field in fb) {
fb; // good fb is Foo
} else {
fb; // good fb is Bar
}
if (#field in fs) {
fs; // good fs is FooSub
} else {
fs; // good fs is never
}
if (#field in b) {
b; // good b is 'Bar & Foo'
} else {
b; // good b is Bar
}
if (#field in fsb) {
fsb; // good fsb is FooSub
} else {
fsb; // good fsb is Bar
}
if (#field in fsfb) {
fsfb; // good fsfb is 'Foo | FooSub'
} else {
fsfb; // good fsfb is Bar
}
class Nested {
m(v: any) {
if (#field in v) {
v; // good v is Foo
}
}
}
}
}
class FooSub extends Foo { subTypeOfFoo = true }
class Bar { notFoo = true }
function badSyntax(v: Foo) {
return #field in v; // Bad - outside of class
}
//// [privateNameInInExpression.js]
"use strict";
class Foo {
#field = 1;
static #staticField = 2;
#method() { }
static #staticMethod() { }
goodRhs(v) {
const a = #field in v;
const b = #field in v.p1.p2;
const c = #field in v;
const d = #field in v;
const e = #field in v;
for (let f in #field in v) { /**/ } // unlikely but valid
}
badRhs(v) {
const a = #field in v; // Bad - RHS of in must be object type or any
const b = #fiel in v; // Bad - typo in privateID
const c = (#field) in v; // Bad - privateID is not an expression on its own
for (#field in v) { /**/ } // Bad - 'in' not allowed
for (let d in #field in v) { /**/ } // Bad - rhs of in should be a object/any
}
whitespace(v) {
const a = v && /*0*/ #field /*1*/
/*2*/ in /*3*/
/*4*/ v; /*5*/
}
flow(u, n, fb, fs, b, fsb, fsfb) {
if (typeof u === 'object') {
if (#field in n) {
n; // good n is never
}
if (#field in u) {
u; // good u is Foo
}
else {
u; // good u is object | null
}
if (u !== null) {
if (#field in u) {
u; // good u is Foo
}
else {
u; // good u is object
}
if (#method in u) {
u; // good u is Foo
}
if (#staticField in u) {
u; // good u is typeof Foo
}
if (#staticMethod in u) {
u; // good u is typeof Foo
}
}
}
if (#field in fb) {
fb; // good fb is Foo
}
else {
fb; // good fb is Bar
}
if (#field in fs) {
fs; // good fs is FooSub
}
else {
fs; // good fs is never
}
if (#field in b) {
b; // good b is 'Bar & Foo'
}
else {
b; // good b is Bar
}
if (#field in fsb) {
fsb; // good fsb is FooSub
}
else {
fsb; // good fsb is Bar
}
if (#field in fsfb) {
fsfb; // good fsfb is 'Foo | FooSub'
}
else {
fsfb; // good fsfb is Bar
}
class Nested {
m(v) {
if (#field in v) {
v; // good v is Foo
}
}
}
}
}
class FooSub extends Foo {
subTypeOfFoo = true;
}
class Bar {
notFoo = true;
}
function badSyntax(v) {
return #field in v; // Bad - outside of class
}
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