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Improved `assert_compile_time_raise` based on this comment by Andrea Leopardi: http://andrealeopardi.com/posts/compile-time-work-with-elixir-macros/#comment-2347206739
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| ExUnit.start() | |
| defmodule CompileTimeAssertions do | |
| defmacro assert_compile_time_raise(expected_exception, expected_message, fun) do | |
| # At compile-time, the fun is in AST form and thus cannot raise. | |
| # At run-time, we will evaluate this AST, and it may raise. | |
| fun_quoted_at_runtime = Macro.escape(fun) | |
| quote do | |
| assert_raise unquote(expected_exception), unquote(expected_message), fn -> | |
| Code.eval_quoted(unquote(fun_quoted_at_runtime)) | |
| end | |
| end | |
| end | |
| end |
This works:
assert_raise SomethingError, fn ->
quote do
# something
end
|> Code.eval_quoted()
end
This is much later, but this discussion has been very helpful, thanks!
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Since we're looking for a compile-time raise, just evaluating the function like this (as opposed to evaluating the function body, or evaluating a function call) should be enough.