Proper way to apply a unique template to only one page in the root folder of content

[jinkuhu]

I have multiple files in the root folder of content, like about us.en.md, advertising.en.md and etc.
But I need to apply a unique post template to only one file, let’s say test.en.md.

It applies \_default\single.html to all single pages but not test.en.md, and it should apply test.html template to test.en.md only.

How should I define the rule that test.en.md will be rendered by test.html template?
If possible, where should I put test.html?

Thanks.

[alexandros]

The simplest way would be to assign a type = "test" parameter in the front matter of the relevant content file for example test.en.md and then under /layouts/ create the relevant template under/layouts/test/single.html.

[jinkuhu]

Great. I works properly.
Thanks.