RubyZip successfully opens a completely blank "zip file" #539
Description
> Zip::File.open_buffer('')
=> #<Zip::File:0x00007f5e6803de50 @entry_set=#<Zip::EntrySet:0x00007f5e6803dcc0 @entry_set={}>, @comment="", @name=#<StringIO:0x00007f5e6803de78>, .......
The expectation would be that such attempt fails with an "invalid ZIP format" error, as the "file" doesn't even have the ZIP signature ('PK') at the start.