error[internal]: left behind trailing whitespace

[hellow554]

Describe the bug

rustfmt fails with an internal error:

error[internal]: left behind trailing whitespace
 --> stdin:3:3:0
  |
3 |
  | ^^^^^^^^
  |

warning: rustfmt has failed to format. See previous 1 errors.

To Reproduce

echo 'Zm4gdHJpbUdvb2QoKSB7CiAgICBpZiBsZXQgU29tZShxKSA9IGxhc3QgJiYgaSAhPSAwIHsKICAgICAgICAKICAgICAgICB9Cn0K' | base64 -d | rustfmt

Meta

• rustfmt 1.4.36-stable (7de6968 2021-02-07)
• From where did you install rustfmt?: rustup
• How do you run rustfmt: rustfmt

[hellow554]

This is probably due to the new if let chain feature

[calebcartwright]

Thanks for the report!

[hellow554]

Also occurs on rustfmt 2.0.0-rc.2-nightly (94035f91 2021-04-07)