Description

When you set up the Paket bootstrapper to run in "Magic mode" and then run paket init, it deletes the paket.exe file.

Repro steps

1. On Linux, create an empty folder to represent a brand-new project: mkdir $HOME/bugrepro
2. mkdir $HOME/bugrepro/.paket
3. Download the Paket bootstrapper and put it in $HOME/bugrepro/.paket/paket.exe
4. Run mono $HOME/bugrepro/.paket/paket.exe init
5. Result: the paket.exe file disappears from $HOME/bugrepro/.paket/ and you can't run any further Paket commands!
6. The only thing remaining in the .paket/ folder after these steps is the paket.targets file.

Expected behavior

The paket.exe file stays where the user put it.

Actual behavior

The paket.exe file disappears.

Known workarounds

After paket.exe disappears, if you look in the /tmp folder, you can find paket_(hash).exe and copy that into your .paket folder as paket.exe. But an F# beginner won't know to look there.

System information

OS: Linux Mint 18.1 Serena (based on Ubuntu 16.04 Xenial)
Paket version: 5.1.7