Run doctests inside `.ex` files

I’m using VSCode, and syntax highlighting doesn’t work with .exs files.

Confoundingly, it seems that mix test will only include .exs files.

Is it possible to have both syntax highlighting and doctests in a .ex file?

You can enable doctests by adding doctest MyModule to the test module as seen here

Syntax highlighting is a completely different thing.

I never had any issues with *.exs back when I used vscode.

If in doubt, just select “elixir” from the list of languages for the file. As a mouse user it’s somewhere in the bottom right, IIRC.

I should have said compiler error syntax highlighting, which isn’t supported:

And this definitely works in a .ex (not .exs file)? This and my previous experience seemed show it didn’t work with .ex` files.

Yes, that is referring to test files (that end with _test.exs). But these are doctests within a module .ex. Here is another example of how to set it up and use it.