e1c8dc2768
* Remove the narrow-to-fresh rule added with boolean literals
* Revert "Remove the narrow-to-fresh rule added with boolean literals"
This reverts commit 9f96fe5da3.
* Only apply freshness to booleans for now
* Add largeish example from issue
* Should be AND not OR
* Add minor improvements suggested by @ahejelsberg
* Reorder conditional a bit
61 lines
1.3 KiB
TypeScript
61 lines
1.3 KiB
TypeScript
function f1() {
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let b = true;
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let obj = { b };
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// Desired: OK
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// 3.0: OK
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// 3.1 as-is: OK
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// 3.1 minus widening propagation: error
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obj.b = false;
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}
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function f2() {
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type Element = (string | false);
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type ElementOrArray = Element | Element[];
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let el: Element = null as any;
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let arr: Element[] = null as any;
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let elOrA: ElementOrArray = null as any;
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// Desired/actual: All OK
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let a1: ElementOrArray = el;
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let a2: ElementOrArray = arr;
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let a3: ElementOrArray = [el];
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let a4: ElementOrArray = Array.isArray(elOrA) ? elOrA : [elOrA];
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// Desired: OK
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// 3.0: Error
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// 3.1: OK
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let a5: ElementOrArray = [...Array.isArray(elOrA) ? elOrA : [elOrA]];
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}
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function f3() {
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type XY = 'x' | 'y';
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const x: XY = 'x';
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let x2 = x;
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// Desired: OK (up for debate?)
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// 3.0: Error
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// 3.1 as-is: OK
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x2 = 'y';
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// Desired/actual: All OK
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let x3: XY = x;
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x3 = 'y';
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}
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function f4() {
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const x: boolean = true;
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let x1 = x;
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// Desired: OK
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// 3.0: OK
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// 3.1: OK
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// 3.1 minus widening propagation: error
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x1 = false;
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}
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function f5() {
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type XY = 'x' | 'y';
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let arr: XY[] = ['x'];
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arr = ['y'];
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// Desired: OK
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// Error in all extant branches
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arr = [...['y']];
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} |