"rustup self uninstall" causes data loss, leaves behind only cargo binaries

I just had a bizzare experience with rustup - unfortunately, one that lost me quite a few hours of work (which would have been many times more, without a backup).

Here's a rough sketch of what happened, as far as I can tell:

1. Install "stable" and "nightly" using rustup

2. rustup self update, to ensure newest

3. Update "stable" and "nightly" again, to ensure newest

4. I had a problem where ~/.cargo/bin was added to my ~/.zshrc, which gave me $PATH inclusion for the commands in interactive shells. However, I have some build scripts for various things that like to call cargo or rust as well, and these fail, since they're not running under interactive shells.

5. On my workstation, I have ~/bin in the default path, to allow users to install local binaries. This solves the problem, as long as cargo and rustc are symlinked to ~/bin.

6. To make it "just work", I symlinked ~/.cargo/bin to ~/bin, so rustup would effectively install in ~/bin.

Since I had some more problems, I finally decided to try the following commands:

$ rustup toolchain uninstall stable
$ rustup toolchain uninstall nightly
$ rustup self uninstall

To my shock, I see that my ~/bin folder has been all but completely destroyed. To provide some salt for the wound, the only files NOT removed, are the rustup ones:

$ ls -l ~/bin
total 67740
-rwxrwxr-x 1 chrivers chrivers 10649744 Apr 17 22:41 cargo
-rwxr-xr-x 6 chrivers chrivers  9785208 Apr 17 22:13 rls
-rwxr-xr-x 6 chrivers chrivers  9785208 Apr 17 22:13 rustc
-rwxr-xr-x 6 chrivers chrivers  9785208 Apr 17 22:13 rustdoc
-rwxr-xr-x 6 chrivers chrivers  9785208 Apr 17 22:13 rust-gdb
-rwxr-xr-x 6 chrivers chrivers  9785208 Apr 17 22:13 rust-lldb
-rwxr-xr-x 6 chrivers chrivers  9785208 Apr 17 22:13 rustup

Whiskey Tango Foxtrot.

The dirs .cargo and .rustup are gone, as are all my binaries and shell scripts. This is a pretty catastrophic result.

Start at the rustup self uninstall entry point and reproduce the reported sequence with a symlinked ~/.cargo/bin. Trace which paths the uninstall operation removes, then add coverage for preserving files outside rustup's managed installation; done means the command no longer deletes unrelated files in ~/bin.