'arc diff' doesn't stop at lint failure

I ran arc diff --no-amend. There was a lint failure but the diff was created anyway. I pulled my Arcanist repo recently, so I’m wondering if it’s a recent regression?

$ arc diff --no-amend
Linting...
>>> Lint for REDACTED.tsx:


   Error  (S&RX) Lint
    'REDACTED' is defined but never used. Allowed unused
    vars must match /^(h|u)$/u. (@typescript-eslint/no-unused-vars)

               9 REDACTED
              10 REDACTED
              11 REDACTED
    >>>       12 import * as REDACTED from 'REDACTED';
                             ^
              13 REDACTED
              14 REDACTED
              15 REDACTED
 LINT ERRORS  Lint raised errors!
Running unit tests...
*** Checking if your local commits have been pushed to GitHub
*** Running command: 'git --no-pager log "@{upstream}..HEAD" 2>&1'
*** Exit code: 0
   PASS   <1ms★  REDACTED-unit-engine
 UNIT OKAY  No unit test failures.
 SKIP STAGING  No staging area is configured for this repository.
Created a new Differential revision:
        Revision URI: https://REDACTED/D19579

Included changes:
  M       REDACTED
  M       REDACTED
  M       REDACTED
  M       REDACTED
  D       REDACTED
  M       REDACTED
  D       REDACTED
  M       REDACTED
  M       REDACTED
  M       REDACTED
  M       REDACTED

This is a recent regression and should be fixed fairly soon.