auto parameters disables autorendering causing a blank page

[TankTheFrank]

Please answer these questions before submitting your issue. Thanks!

1. What version of Go and beego are you using (bee version)?

go 1.9.2
beego 1.9.0

2. What operating system and processor architecture are you using (go env)?
   darwin/amd64

3. What did you do?
   If possible, provide a recipe for reproducing the error.
   A complete runnable program is good.

Added an auto-parameter method to a controller instead of an empty method/Ctx.Input.Param way.

Using this:

// @router /:id [get]
func (c *MyController) Show(id int64) {
}

outputs nothing - auto template rendering is ignored. Adding c.Render() shows the expected output.

Changing it to "old way" also renders the template.

// @router /:id [get]
func (c *MyController) Show() {
id := c.Ctx.Input.Param(":id")
}

4. What did you expect to see?

The template rendered

5. What did you see instead?

Nothing, 0 bytes

[TankTheFrank]

I believe the issue is here, correct me if I'm wrong:

https://github.com/astaxie/beego/blob/bf5c5626ab429e66d88602e1ab1ab5fbf4629a01/router.go#L951-L963

The idea is to disable the render if we have some kind of 'result' from a custom HandlerFunc (not a post, get, put, etc method). But there is no check if there is actually output a custom method before setting the status to 200 which in turn blocks the renderer. So the fix should be changing

if !context.ResponseWriter.Started && context.Output.Status == 0 { context.Output.SetStatus(200) }

with
if !context.ResponseWriter.Started && len(results) > 0 && context.Output.Status == 0 { context.Output.SetStatus(200) }

I'll open a pull request unless I'm missing something about the logic.