Factorio Forums

I found that if the mod name is "_test"

The directory structure is

_test/
├── data.lua
├── info.json
└── test.png

In this case

icon = "__test__/test.png"
error:Path __test__/test.png does not match anyenabled mod.

and

icon = "___test__/test.png"
error:Path ___test__/test.png not matching the resource path pattern:__source__/path

But without the path, the mod performs the other functions normally, no errors.

Don't create mods with underscores in it. This just causes confusion.
Underscores in the folder name for the mod should only be used to separate the name from the version of the mod.