Task of error handler with Koa 2 cannot pass

[xie-qianyue]

In the task of error handler, the response cannot be set with ctx.body = 'internal server error'. Here is my error handler :

function errorHandler(ctx, next) {
    try {
       return next();
    }
    catch(err) {
      ctx.status = err.status || 500;     
      ctx.body = 'internal server error';   
      // emit can't help
      // ctx.app.emit('error', err, ctx);      
    }
}

When I verify my codes, the third test always fails :
3. ACTUAL: "responds "Internal Server Error" when requesting /error"
3. EXPECTED: "responds "internal server error" when requesting /error"

[dead-horse]

this project is only test in koa@1 now. :(

[xie-qianyue]

@dead-horse Thanks for your reply. I've created a pull request which modifies the README to figure out that.

[scorbiclife]

Two things of note, possibly spoilers (click to expand)

About the solution criteria

It seems a passing solution only needs a matching response body, not the response status.
I guess the author intended a response 200 with different message bodies,
while some readers (including myself) think the status code has to match the route.
(So that /500 returns HTTP 500 etc.)

About setting the response body with HTTP status >= 500

As per the http-errors docs,
it seems one needs to set err.expose = true in order to set a custom response body.
That certainly doesn't seem like the author's intention, but is one way to solve the problem.

To summarize I think elaborating the solution criteria might be a good idea.