javascript - Jasmine .toThrow 错误

Question

我有以下功能:

function checkforLandP(n){
if(n[0]=== '£' && n[n.length-1] === 'p'){
    // remove the p 
    n =n.slice(0, -1);
    // remove the £
    n = n.substr(1);

    // take the value  and multiply by 100
    n =Math.round(n*100);
    if(isNaN(n)){
        window.alert('Please enter a valid number');
        throw ('Please enter a valid number');
    }
}
return n;
};

和以下测试:

describe("check for £ and p", function(){
  it("checks the array for £ and p together", function(){
    expect(checkforLandP('£234p')).toBe(23400);
    expect(checkforLandP(234)).toBe(234);
    expect(checkforLandP('asdfsdf')).toBe('asdfsdf');
    expect(checkforLandP('£asdfsdfp')).toThrow("Please enter a valid number");
    });
});

测试失败返回:Please enter a valid number thrown

我一直在研究语法，几乎一切似乎都没有问题。

Answer 1

你应该传递一个将被执行的函数而不是结果，你可以用匿名函数试试这个。

expect(function() {checkforLandP('£asdfsdfp'); } ).toThrow("Please enter a valid number");

另请参阅此答案:

https://stackoverflow.com/a/4144803/2419919