Last letter in derive statement gets removed by rustfmt nightly

[cdbrkfxrpt]

Describe the bug

On the nightly toolchain, rustfmt removes the last letter from any derive statement, i.e.

#[derive(Debug)]

becomes

#[derive(Debu)]

In my rustfmt.toml, I have the following line:

# "Block" | "Visual"
indent_style = "Visual"

If I comment this line (or change it to "Block", which is the default) the issue goes away (but formatting happens completely differently, of course, so this is not a viable fix).

To Reproduce

Heads up: I'm only able to reproduce this on my laptop. It does not reproduce on my workstation. However I have no clue what the difference between the systems may be; they're both Debian sid on latest updates, both have Rust installed and updated via rustup, both have the exact same setup in terms of terminal emulator, shell, environment,etc.

To reproduce - if you can - simple throw the following into a file (let's call it test.rs):

#[derive(Debug)]
struct Foo {
  some:   usize,
  member: String,
}

Put the file in a directory together with a rustfmt.toml file containing:

# "Block" | "Visual"
indent_style = "Visual"

Finally, run rustfmt test.rs.

Expected behavior

I expect rustfmt not to remove letters from my code in this fashion.

Meta

• rustfmt version: rustfmt 1.4.29-nightly (70ce182 2020-12-04)
• From where did you install rustfmt?: rustup
• How do you run rustfmt: normally via vim but this issue shows up regardless (i.e. I can reproduce using rustfmt or cargo fmt)

[calebcartwright]

Closing as duplicate of #4584, already fixed in the latest 1.4.30 version which I believe will be in the next published nightly (otherwise the following one)

[cdbrkfxrpt]

i'm sorry, i actually searched "derive" in the issues but #4584 didn't pop up for some reason.

thanks for the info though.

[calebcartwright]

No worries!