GSoC project: dialyzer story for the Elixir ecosystem

[dimitarvp]

How to make Dialyzer more strict?

If we have function with typespec that always returns value with incorrect type @spec hello(integer()) :: map() def hello(int) do case int do 1 -> :foo _ -> :wtf end end then Dialyzer generates warning, good. It is as expected. done in 0m1.08s lib/hello.ex:16: Invalid type specification for function 'Elixir.Hello':hello/1. The success typing is (_) -> 'foo' | 'wtf' done (warnings were emitted) But if @spec hello(integer()) :: map() def hello(int) do case int …

This is one of the threads that gives good bits of info.