Not all executables are found in a shell command on Windows

[pawamoy]

Describe the bug
The first exec of a shell command on Windows is "whiched" to make sure it is found. However a shell command can run multiple executables (with pipes, etc.), so some exec might not be "whiched" and the process results in "exec is not recognized as a command...".

To Reproduce
On Windows, run:

from failprint.runners import run

run("poetry show | grep failprint")

There's a high chance grep is not found.

Expected behavior
Every executable is correctly "whiched". Or some other clever trick.

System:

• failprint version: 0.4.1
• Python version: 3.6
• OS: Windows

Additional context
Aditionally, the output often cannot be decoded as UTF-8 (see #7).

[pawamoy]

I don't see any robust method to prefetch absolute paths of all the executables used in a shell command.
Users will have to make sure they use the absolute path of those execs when they build the command they pass to failprint, if they want it to work on Windows. I can't stand Windows anymore and don't want to waste my time on it :O