incomplete_input?

        # Encoding::InvalidByteSequenceError.incomplete_input?

(from ruby core)
### Implementation from InvalidByteSequenceError
---
    ecerr.incomplete_input?         -> true or false

---

Returns true if the invalid byte sequence error is caused by premature
end of string.

    ec = Encoding::Converter.new("EUC-JP", "ISO-8859-1")

    begin
      ec.convert("abc\xA1z")
    rescue Encoding::InvalidByteSequenceError
      p $!      #=> #<Encoding::InvalidByteSequenceError: "\xA1" followed by "z" on EUC-JP>
      p $!.incomplete_input?    #=> false
    end

    begin
      ec.convert("abc\xA1")
      ec.finish
    rescue Encoding::InvalidByteSequenceError
      p $!      #=> #<Encoding::InvalidByteSequenceError: incomplete "\xA1" on EUC-JP>
      p $!.incomplete_input?    #=> true
    end