问题：
When I have a loader configuration with multiple tests matching a file, I would expect only the first matching loader to be used but that doesn't seem to be the case.当我有一个加载器配置与多个测试匹配一个文件时，我希望只使用第一个匹配的加载器，但情况似乎并非如此。
I tried reading the source but even when I found the bit that I think implements the loading I can't understand how it behaves.我尝试阅读 源代码，但即使发现我认为实现加载的位，我也无法理解它的行为方式。
The documentation doesn't mention how that situation should behave either.文档也没有提到这种情况应该如何表现。