IEx.configure相当于混合测试？

Question

调试测试时，很容易将一些IO.inspect语句放在那里看看发生了什么。这很好，直到物体变得太大。

什么是mix相当于iex的IEx.configure [inspect: [limit: 1000]]运行时mix test？

Answer 1

IEx.configure [inspect: [limit: 1000]]只更改iex自动调用的inspect对于输入的每个表达式的选项，并且不会更改实际的IO.inspect函数的行为。你必须围绕IO.inspect和使用创造一个包装，而不是IO.inspect：

test "the truth" do 
    list = Enum.to_list(1..100) 
    IO.inspect list 
    i list 
end 

defp i(item, opts \\ []) do 
    IO.inspect(item, Keyword.put(opts, :limit, 1000)) 
end 

输出：

$ mix test 
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 
23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 
43, 44, 45, 46, 47, 48, 49, 50, ...] 
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 
23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 
43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 
63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 
83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100] 
. 

Finished in 0.03 seconds 
1 test, 0 failures