TypeScript版本： v4.0.5
搜索词： destructuring assignment , Object literal may only specify known properties
代码

declare function foo<T extends { dataType: 'a' | 'b'; }>(template: T): [T, any, any]; //<-- there no error, when it is [any,any,any]
declare function bar<T extends { dataType: 'a' | 'b'; }>(template: T): [T, any];

function test_foo() {

  const [, ,] = foo({ dataType: 'a', day: 0 });
  const [x, y, z] = foo({ dataType: 'a', day: 0 });
  const [, , t] = foo({ dataType: 'a', day: 0 }); //<-- red line under the `day`
  console.log(x, y, z, t);
}

function test_bar() {

  const [,] = bar({ dataType: 'a', day: 0 });
  const [x, y] = bar({ dataType: 'a', day: 0 });
  const [, z] = bar({ dataType: 'a', day: 0 });//<-- red line under the `day`
  console.log(x, y, z);
}

预期行为：

无编译错误

实际行为：

Argument of type '{ dataType: "a"; day: number; }' is not assignable to parameter of type '{ dataType: "a" | "b"; }'. Object literal may only specify known properties, and 'day' does not exist in type '{ dataType: "a" | "b"; }'.

Playground链接：

link

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