Maciek Rząsa

1. The documentation of `Float#to_d` still mentions the old default value of `precision` (`Float::DIG`). I've updated it and described what does the `precision=0` mean. 2. The description of `ndigits=0` disappeared...

Fixes https://github.com/ruby/bigdecimal/issues/78 by describing behaviour for positive and negative zero in the docs.

Fix #20919: clear ungetc buffer on IO#seek with encoding

1

Changes: * When `IO#seek` is called, it clears `cbuf` (the `ungetc` buffer, not only the `rbuf` (the read buffer` When we call `IO#ungetc` on a file that not requires encoding,...