% python repro.py
x, y=(1, 2)

% ruff --version
ruff 0.0.285

% ruff --isolated repro.py 
warning: Linting panicked repro.py: 

panicked at 'byte index 18446744073709551615 is out of bounds of `x, y=`', crates/ruff_python_parser/src/string.rs:321:30
Backtrace:    0: _rust_eh_personality
   1: _main
   2: _rust_eh_personality
   3: _rust_eh_personality
   4: _rust_eh_personality
   5: _rust_eh_personality
   6: __rjem_je_witnesses_cleanup
   7: _main
   8: __rjem_je_witnesses_cleanup
   9: _main
  10: _main
  11: _main
  12: _main
  13: _main
  14: _main
  15: _main
  16: _main
  17: _main
  18: _main
  19: _main
  20: _main
  21: __mh_execute_header
  22: __mh_execute_header
  23: _main