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//// [literalFreshnessPropagationOnNarrowing.ts]
function f1() {
let b = true;
let obj = { b };
// Desired: OK
// 3.0: OK
// 3.1 as-is: OK
// 3.1 minus widening propagation: error
obj.b = false;
}
function f2() {
type Element = (string | false);
type ElementOrArray = Element | Element[];
let el: Element = null as any;
let arr: Element[] = null as any;
let elOrA: ElementOrArray = null as any;
// Desired/actual: All OK
let a1: ElementOrArray = el;
let a2: ElementOrArray = arr;
let a3: ElementOrArray = [el];
let a4: ElementOrArray = Array.isArray(elOrA) ? elOrA : [elOrA];
// Desired: OK
// 3.0: Error
// 3.1: OK
let a5: ElementOrArray = [...Array.isArray(elOrA) ? elOrA : [elOrA]];
}
function f3() {
type XY = 'x' | 'y';
const x: XY = 'x';
let x2 = x;
// Desired: OK (up for debate?)
// 3.0: Error
// 3.1 as-is: OK
x2 = 'y';
// Desired/actual: All OK
let x3: XY = x;
x3 = 'y';
}
function f4() {
const x: boolean = true;
let x1 = x;
// Desired: OK
// 3.0: OK
// 3.1: OK
// 3.1 minus widening propagation: error
x1 = false;
}
function f5() {
type XY = 'x' | 'y';
let arr: XY[] = ['x'];
arr = ['y'];
// Desired: OK
// Error in all extant branches
arr = [...['y']];
}
//// [literalFreshnessPropagationOnNarrowing.js]
function f1() {
var b = true;
var obj = { b: b };
// Desired: OK
// 3.0: OK
// 3.1 as-is: OK
// 3.1 minus widening propagation: error
obj.b = false;
}
function f2() {
var el = null;
var arr = null;
var elOrA = null;
// Desired/actual: All OK
var a1 = el;
var a2 = arr;
var a3 = [el];
var a4 = Array.isArray(elOrA) ? elOrA : [elOrA];
// Desired: OK
// 3.0: Error
// 3.1: OK
var a5 = (Array.isArray(elOrA) ? elOrA : [elOrA]).slice();
}
function f3() {
var x = 'x';
var x2 = x;
// Desired: OK (up for debate?)
// 3.0: Error
// 3.1 as-is: OK
x2 = 'y';
// Desired/actual: All OK
var x3 = x;
x3 = 'y';
}
function f4() {
var x = true;
var x1 = x;
// Desired: OK
// 3.0: OK
// 3.1: OK
// 3.1 minus widening propagation: error
x1 = false;
}
function f5() {
var arr = ['x'];
arr = ['y'];
// Desired: OK
// Error in all extant branches
arr = ['y'];
}
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