cargo add on a full disk results in Cargo.toml becoming empty

[rustrust]

I ran cargo add on a disk which was already full and this resulted in my Cargo.toml becoming an empty file.

$ rustc --version
rustc 1.72.0 (5680fa18f 2023-08-23)
$ cargo --version
cargo 1.72.0 (103a7ff2e 2023-08-15)

$ cargo add clap --features derive
    Updating crates.io index
      Adding clap v4.4.4 to dependencies.
             Features:
             + color
             + derive
             + error-context
             + help
             + std
             + suggestions
             + usage
             - cargo
             - debug
             - deprecated
             - env
             - string
             - unicode
             - unstable-doc
             - unstable-styles
             - unstable-v5
             - wrap_help
error: failed to write `/myproject/Cargo.toml`

Caused by:
  No space left on device (os error 28)

After this Cargo.toml is a blank file!

[epage]

The fix for this would have overlap with the fix for #11386 (atomic writes)

[calavera]

I believe #12744 fixed this problem. The new write_atomic operation will fail to create the temp file without deleting the content of the Cargo.toml file.

[weihanglo]

Nice catch. I believe so. Thank you :)