File.open w/ File::RDWR should write \r\n but gets should read as \n after rewind on windows

[enebo]

Environment

Note: duplicated issue from #3738. This is broken differently than 1.7's version of this bug so I made a new issue to track it on 9k.

Broken on 9.0.5.0.

Expected Behavior

For the following script:

file = "temptemp"

File.open(file, "w") {}
File.open(file, File::RDWR) do |f|
  f.puts("writing")  # writes "writing\r\n"
  f.flush            # force to disk
  gets               # do not continue until you can verify it was written right
  f.rewind           # backup
  p f.gets           # read it but it should be "writing\n"
end
File.unlink(file)

The comments dictate how it should behave.

Actual Behavior

On JRuby 9.0.5.0 it wil write "writing\n" instead of "writing\r\n" but it will read "writing\n".

[enebo]

Bumping discovered windows issues from 1.7 windows work to 9.1.1.0 because we have not CI-greened 9k on appveyor yet. Next release we will have greenness.

[headius]

Next release, and the one after it, still don't have greenness on Appveyor...and this is an internal report, so I guess we bump it again.

[ahorek]

file = "temptemp"
File.open(file, "wb") { |f| f.puts("\r\n") }
File.open(file, "r") { |f| p f.gets }
File.unlink(file)

on windows it should print "\n" but it prints "\r\n"

[headius]

Based on @ahorek example this is still broken on Windows. It writes crlf to the file and reads it back in as crlf. Seems like binary mode is not working properly for this case but I am confirming CRuby behavior now.

[headius]

CRuby also writes CRLF to the file. The read is where it normalizes back to just LF, due to the mode not being b.

On JRuby:

• mode wb with a write of CRLF writes CRLF
• mode w with a write of CRLF writes CRLF
• mode w with a write of LF writes CRLF
• more rb with a file containing CRLF reads CRLF
• mode r with a file containing CRLF reads CRLF

On CRuby:

• mode wb with a write of CRLF writes CRLF
• mode w with a write of CRLF writes CRLF
• mode w with a write of LF writes CRLF
• mode r with a file containing CRLF reads LF
• mode rb with a file containing CRLF reads CRLF

Only the non-binary read mode seems to be in error here.

[headius]

It appears at a glance that we are setting up the right newline conversions in the IO transcoding pipeline, so this one will take more stepping to see why it is not normalizing CRLF to LF on a non-binary read.

Not a critical item so punting to 9.3.1.