Conflict with net/http?

[hallerm]

With ruby 2.6.10 and mail 2.8.0 installed, requiring 'mail' followed by 'net/http' shows a conflict with the built-in net/protocol. I have not yet observed any functional problems, but it seems problematic that the net-protocol gem code is being overwritten with the built-in library code.

$ irb
irb(main):001:0> require 'mail'
=> true
irb(main):002:0> require 'net/http'
/opt/homebrew/Cellar/ruby@2.6/2.6.10/lib/ruby/2.6.0/net/protocol.rb:66: warning: already initialized constant Net::ProtocRetryError
/opt/homebrew/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.0/lib/net/protocol.rb:68: warning: previous definition of ProtocRetryError was here
/opt/homebrew/Cellar/ruby@2.6/2.6.10/lib/ruby/2.6.0/net/protocol.rb:206: warning: already initialized constant Net::BufferedIO::BUFSIZE
/opt/homebrew/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.0/lib/net/protocol.rb:213: warning: previous definition of BUFSIZE was here
/opt/homebrew/Cellar/ruby@2.6/2.6.10/lib/ruby/2.6.0/net/protocol.rb:503: warning: already initialized constant Net::NetPrivate::Socket
/opt/homebrew/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.0/lib/net/protocol.rb:550: warning: previous definition of Socket was here
=> true

Version 2.7.1 does not have this problem.

[dgm]

Also a problem on ruby 2.7.7 and mail 2.8.0

[lovitt]

This problem is described well here.

It sounds like the right solution is for mail to declare net-http as a dependency.

[masonlouchart]

I encountered this conflict when trying to update Rails (to 6.1.7.2) for fixing security issue CVE-2023-22794.
As (temporary?) solution I locked mail version strictly under 2.8.
Other solution applied: #1523 (comment)

[crivotz]

As temporary solution you can also add gem "net-http" to your Gemfile as suggested in reference by @lovitt

[masonlouchart]

@crivotz Actually during PR review we decided to do as you suggested (add net-http to the Gemfile).
It introduced an issue with CircleCI default gem uri but it's another story (we fixed it too).

[crivotz]

@crivotz Actually during PR review we decided to do as you suggested (add net-http to the Gemfile). It introduced an issue with CircleCI default gem uri but it's another story (we fixed it too).

I just had trouble deploying because of the uri issue if I pass the net-http gem in the Gemfile in production I get:

You have already activated uri 0.10.1, but your Gemfile requires uri 0.12.0. Since uri is a default gem, you can either remove your dependency on it or try updating to a newer version of bundler that supports uri as a default gem

So for the moment I rollback to 2.7.1 version of mail

[masonlouchart]

You have already activated uri 0.10.1, but your Gemfile requires uri 0.12.0. Since uri is a default gem, you can either remove your dependency on it or try updating to a newer version of bundler that supports uri as a default gem

We ran through this error too.
The solution we applied is to change the Ruby default gem version.
We added a step to the CI configuration that deploy the application before the dependencies installation.

- run: sudo gem install uri -v0.12.0 --default

[evolve2k]

I've been pairing on this with a few folk at RubyRetreat AU 2024 in an attempt to get to the bottom of this. Thanks crew! @KJTsanaktsidis @moxvallix @layerssss

The impact of this issue extends beyond the mail gem and is likley affecting most apps attempting to upgrade from Rails 5.1 to Rails 6.x on their journey through a rails upgrade path. Rails relies on this mail gem which in turn is relying on net-http, which is where the conflicts lie.

net/http is only gemified from ruby 3.0 BUT all versions of the net-http gem (v0.1.0 up to latest 0.4.1) list an incorrect minimum support ruby as being >= 2.6.0, but it should be listed as >=3.0

A few compounding issues:

• net-http gem on rubygems lists incorrect minimum ruby
• ruby standard library doesnt set clear version dependancies on net-http amplifying this issue.
• mail brings in net-http, net-imap, net-smpt they all have the same problem, but this adds further confusion

WORKAROUND PROCESS:
Review Gemfile.lock and look for dependancies on net-http, in this case the mail gem.
Pin each of the dependant gems to a version circa ruby 2.6, eg around 2018.

SOLVE WITH:
gem "mail", "~> 2.7.0". # a release of the gem that references earlier dependancies

[radar]

@evolve2k great to see you participating here mate :)

I've just got commit rights to this project and I think we could work on a proper fix for this for the next mail gem version.

Would anyone here like to take a stab at:

1. A small script to reproduce the issue (ideally with Ruby + gem versions specified)?
2. A patch to fix the issue?

I ask for #1 here as I've just tried to reproduce this myself but I think I might be using the wrong version of Ruby (3.4.1 is what I'm using), but looking again at OP perhaps I should be trying the (EOL'd) 2.6.

[radar]

I can indeed reproduce this with Ruby 2.6:

 irb -W
irb(main):001:0> require 'mail'
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/mail-2.8.1/lib/mail/parsers/date_time_parser.rb:837: warning: statement not reached
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/mail-2.8.1/lib/mail/parsers/date_time_parser.rb:691: warning: assigned but unused variable - testEof
=> true
irb(main):002:0> require 'net/http'
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:30: warning: method redefined; discarding old protocol_param
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:32: warning: previous definition of protocol_param was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:38: warning: method redefined; discarding old ssl_socket_connect
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:40: warning: previous definition of ssl_socket_connect was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:66: warning: already initialized constant Net::ProtocRetryError
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:68: warning: previous definition of ProtocRetryError was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:79: warning: method redefined; discarding old initialize
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:81: warning: previous definition of initialize was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:82: warning: method redefined; discarding old io
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:84: warning: method redefined; discarding old message
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:86: warning: previous definition of message was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:98: warning: method redefined; discarding old initialize
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:100: warning: previous definition of initialize was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:101: warning: method redefined; discarding old io
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:103: warning: method redefined; discarding old message
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:105: warning: previous definition of message was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:114: warning: method redefined; discarding old initialize
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:116: warning: previous definition of initialize was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:123: warning: method redefined; discarding old io
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:124: warning: method redefined; discarding old read_timeout
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:124: warning: method redefined; discarding old read_timeout=
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:125: warning: method redefined; discarding old write_timeout
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:125: warning: method redefined; discarding old write_timeout=
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:126: warning: method redefined; discarding old continue_timeout
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:126: warning: method redefined; discarding old continue_timeout=
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:127: warning: method redefined; discarding old debug_output
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:127: warning: method redefined; discarding old debug_output=
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:129: warning: method redefined; discarding old inspect
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:133: warning: previous definition of inspect was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:133: warning: method redefined; discarding old eof?
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:137: warning: previous definition of eof? was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:137: warning: method redefined; discarding old closed?
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:141: warning: previous definition of closed? was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:141: warning: method redefined; discarding old close
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:145: warning: previous definition of close was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:151: warning: method redefined; discarding old read
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:155: warning: previous definition of read was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:171: warning: method redefined; discarding old read_all
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:176: warning: previous definition of read_all was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:188: warning: method redefined; discarding old readuntil
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:194: warning: previous definition of readuntil was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:200: warning: method redefined; discarding old readline
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:208: warning: previous definition of readline was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:206: warning: already initialized constant Net::BufferedIO::BUFSIZE
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:214: warning: previous definition of BUFSIZE was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:208: warning: method redefined; discarding old rbuf_fill
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:216: warning: previous definition of rbuf_fill was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:229: warning: method redefined; discarding old rbuf_consume
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:257: warning: previous definition of rbuf_consume was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:254: warning: method redefined; discarding old writeline
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:293: warning: previous definition of writeline was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:262: warning: method redefined; discarding old writing
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:301: warning: previous definition of writing was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:272: warning: method redefined; discarding old write0
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:311: warning: previous definition of write0 was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:308: warning: method redefined; discarding old LOG_off
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:347: warning: previous definition of LOG_off was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:313: warning: method redefined; discarding old LOG_on
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:352: warning: previous definition of LOG_on was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:317: warning: method redefined; discarding old LOG
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:356: warning: previous definition of LOG was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:325: warning: method redefined; discarding old initialize
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:364: warning: previous definition of initialize was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:334: warning: method redefined; discarding old each_message_chunk
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:373: warning: previous definition of each_message_chunk was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:347: warning: method redefined; discarding old each_list_item
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:386: warning: previous definition of each_list_item was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:353: warning: method redefined; discarding old write_message_0
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:392: warning: previous definition of write_message_0 was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:365: warning: method redefined; discarding old write_message
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:404: warning: previous definition of write_message was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:378: warning: method redefined; discarding old write_message_by_block
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:417: warning: previous definition of write_message_by_block was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:397: warning: method redefined; discarding old dot_stuff
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:436: warning: previous definition of dot_stuff was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:401: warning: method redefined; discarding old using_each_crlf_line
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:440: warning: previous definition of using_each_crlf_line was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:413: warning: method redefined; discarding old each_crlf_line
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:452: warning: previous definition of each_crlf_line was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:421: warning: method redefined; discarding old buffer_filling
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:460: warning: previous definition of buffer_filling was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:448: warning: method redefined; discarding old initialize
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:487: warning: previous definition of initialize was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:453: warning: method redefined; discarding old inspect
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:491: warning: previous definition of inspect was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:463: warning: method redefined; discarding old <<
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:501: warning: previous definition of << was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:468: warning: method redefined; discarding old puts
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:506: warning: previous definition of puts was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:472: warning: method redefined; discarding old printf
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:510: warning: previous definition of printf was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:479: warning: method redefined; discarding old initialize
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:517: warning: previous definition of initialize was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:483: warning: method redefined; discarding old inspect
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:521: warning: previous definition of inspect was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:487: warning: method redefined; discarding old <<
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:525: warning: previous definition of << was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:496: warning: method redefined; discarding old call_block
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:534: warning: previous definition of call_block was here
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/2.6.0/net/protocol.rb:503: warning: already initialized constant Net::NetPrivate::Socket
/Users/ryan.bigg/.local/share/mise/installs/ruby/2.6.10/lib/ruby/gems/2.6.0/gems/net-protocol-0.2.2/lib/net/protocol.rb:541: warning: previous definition of Socket was here
=> true

[evolve2k]

Hey @radar, glad to have you looking at this.

I want to lay down the primary usecase of fixing work here as making it so that users can cleanly upgrade old Rails apps through to Rails 5 to Rails 6.1 stages. Currently this issue leads to a cluster of errors, that are so frustrating that anecdotally could be significant in abandonment of folks attempting to upgrade old Rails apps. This will help scope what work is worth and not worth doing.

Addressing the specific issue to fix here, consensus seems to be that if the mail gem explicitly declared these gem dependanices this would sovle a bunch of issues. Ruby 3.0 explicitly loads these gems as default gems whereas pre Ruby 3.0 these are loaded inconsistently (as explained below).

The fix I think is to explicitly load these gems, preferably where ruby < 3.0.
Seems that net-http, net-uri and net-http all have the same issue. So load all three.

There's also a related weird conflict when the 'uri' gem and the 'net-uri' gems are out of whack, so include that explicitly too.

gem "net-http"
gem "net-smtp"
gem "net-uri"
gem "uri"

Actual fix would be, to update the Gemfile/gemspec in the mail gem to:

1. Include the 'uri' gem with an explicit version that will work with 'net-uri' (dunno if this is already there).
2. Include 'net-http', 'net-smtp' and 'net-uri' conditionally if the ruby environment is less than ruby 3.

Below is more context:

This comment from @deivid-rodriguez seems to cover things pretty thoroughly, replace faraday-net_http with mail in your head:

"The proper fix here in my opinion would be that the faraday-net_http gem would declare the net-http gem as a dependency.
This is the explanation of what's happening:

When the faraday-net_http gem is required, it then requires net/http.
Then the stdlib version of net/http is loaded, since bundler doesn't know net-http is a gem dependency, so it doesn't add the gemified version to to the $LOAD_PATH.
Then the stdlib version of net/http requires net/protocol relatively, since that's what it used to happen before these gems were gemified. See ruby/net-http@6da598e. So the stdlib version of net/protocol is loaded.
Then when net-imap is required, it also uses net-protocol but this time the gemified version of net-protocol is used, because net-imap properly declares it as a dependency, so bundler knows about it and has put it in the $LOAD_PATH. This is what causes the double load of net/protocol.
If faraday-net_http explicitly declares net-http as a dependency, then the gemified version of all gems involved will be consistently loaded and there will be no redefinition warnings.
I suggest that you proposed this update to faraday-net_http and in the mean time, you can workaround this issue by adding gem "net-http" to your Gemfile."