50 lines
746 B
JavaScript
50 lines
746 B
JavaScript
var x = undefined;
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var sets = 0;
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var obj = {
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get x() {
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return x;
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},
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set x(value) {
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sets++;
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x = value;
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},
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};
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expect(obj.x ??= 1).toBe(1);
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expect(sets, 1);
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expect(obj.x ??= 2).toBe(1);
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expect(sets, 1);
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var gets = 0;
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var deep = {
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get obj() {
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gets++;
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return obj;
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},
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};
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obj.x = undefined;
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expect(deep.obj.x ??= 1).toBe(1);
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expect(gets, 1);
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expect(deep.obj.x ??= 2).toBe(1);
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expect(gets, 2);
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var key = 0;
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obj.x = undefined;
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expect(obj[++key] ??= 1).toBe(1);
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expect(key, 1);
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key = 0;
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expect(obj[++key] ??= 2).toBe(1);
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expect(key, 1);
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obj.x = undefined;
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key = 0;
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expect(deep.obj[++key] ??= 1).toBe(1);
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expect(gets, 3);
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expect(key, 1);
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key = 0;
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expect(deep.obj[++key] ??= 2).toBe(1);
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expect(gets, 4);
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expect(key, 1);
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