i18n documentation for required belongs_to message
i18n documentation for required belongs_to message

When you don't explicitly provide `optional: true` to a `belongs_to`
definition, rails adds a validation to ensure presence of the
`belongs_to` validation.

However, when the validation is added, it is added with a message key of
`:required`, which was not documented in the "Translations for Active
Record Models" section of the i18n guides.

Here are the lines that add the `:required` message:
https://github.com/rails/rails/blob/c3e3577f9d5058382504773bf0d32afa15cb131e/activerecord/lib/active_record/associations/builder/belongs_to.rb#L136-L138

This commit adds the "non-optional association" validation to the table,
so rails users know how to override the message for this validation. The
default message is "must exist".

baerjam/rails,illacceptanything/illacceptanything,eileencodes/rails,vipulnsward/rails,repinel/rails,untidy-hair/rails,coreyward/rails,MSP-Greg/rails,bolek/rails,mathieujobin/reduced-rails-for-travis,iainbeeston/rails,kachick/rails,felipecvo/rails,Stellenticket/rails,stefanmb/rails,mijoharas/rails,xlymian/rails,deraru/rails,aditya-kapoor/rails,flanger001/rails,iainbeeston/rails,deraru/rails,esparta/rails,mechanicles/rails,felipecvo/rails,travisofthenorth/rails,tjschuck/rails,brchristian/rails,palkan/rails,rails/rails,pvalena/rails,schuetzm/rails,kmcphillips/rails,Vasfed/rails,MSP-Greg/rails,utilum/rails,maicher/rails,illacceptanything/illacceptanything,rails/rails,riseshia/railsguides.kr,mtsmfm/railstest,maicher/rails,marklocklear/rails,odedniv/rails,georgeclaghorn/rails,sergey-alekseev/rails,rossta/rails,flanger001/rails,printercu/rails,prathamesh-sonpatki/rails,hanystudy/rails,bradleypriest/rails,travisofthenorth/rails,schuetzm/rails,illacceptanything/illacceptanything,rails/rails,yahonda/rails,arunagw/rails,yalab/rails,illacceptanything/illacceptanything,yawboakye/rails,koic/rails,kachick/rails,pvalena/rails,travisofthenorth/rails,mtsmfm/rails,palkan/rails,ttanimichi/rails,untidy-hair/rails,mathieujobin/reduced-rails-for-travis,jeremy/rails,sealocal/rails,untidy-hair/rails,betesh/rails,iainbeeston/rails,illacceptanything/illacceptanything,utilum/rails,Erol/rails,mechanicles/rails,richseviora/rails,matrinox/rails,palkan/rails,gcourtemanche/rails,maicher/rails,repinel/rails,coreyward/rails,esparta/rails,rafaelfranca/omg-rails,koic/rails,notapatch/rails,repinel/rails,eileencodes/rails,kenta-s/rails,shioyama/rails,fabianoleittes/rails,joonyou/rails,notapatch/rails,sealocal/rails,rossta/rails,lcreid/rails,gfvcastro/rails,coreyward/rails,joonyou/rails,illacceptanything/illacceptanything,gcourtemanche/rails,yahonda/rails,aditya-kapoor/rails,felipecvo/rails,yahonda/rails,palkan/rails,marklocklear/rails,pschambacher/rails,mohitnatoo/rails,tgxworld/rails,vipulnsward/rails,Spin42/rails,arjes/rails,yawboakye/rails,untidy-hair/rails,yawboakye/rails,joonyou/rails,baerjam/rails,yasslab/railsguides.jp,BlakeWilliams/rails,sergey-alekseev/rails,tijwelch/rails,Edouard-chin/rails,stefanmb/rails,yhirano55/rails,Sen-Zhang/rails,flanger001/rails,kachick/rails,richseviora/rails,ngpestelos/rails,mohitnatoo/rails,Sen-Zhang/rails,matrinox/rails,utilum/rails,odedniv/rails,mohitnatoo/rails,lcreid/rails,baerjam/rails,eileencodes/rails,utilum/rails,elfassy/rails,starknx/rails,tgxworld/rails,kirs/rails-1,schuetzm/rails,samphilipd/rails,mtsmfm/rails,lucasmazza/rails,ledestin/rails,Erol/rails,xlymian/rails,Stellenticket/rails,kddeisz/rails,arunagw/rails,bogdanvlviv/rails,Envek/rails,Vasfed/rails,pschambacher/rails,alecspopa/rails,kddeisz/rails,MichaelSp/rails,mijoharas/rails,yalab/rails,aditya-kapoor/rails,mathieujobin/reduced-rails-for-travis,mtsmfm/rails,deraru/rails,tjschuck/rails,arunagw/rails,georgeclaghorn/rails,illacceptanything/illacceptanything,ttanimichi/rails,tjschuck/rails,Edouard-chin/rails,travisofthenorth/rails,BlakeWilliams/rails,riseshia/railsguides.kr,Sen-Zhang/rails,betesh/rails,georgeclaghorn/rails,elfassy/rails,assain/rails,lucasmazza/rails,yasslab/railsguides.jp,ledestin/rails,MichaelSp/rails,gavingmiller/rails,koic/rails,prathamesh-sonpatki/rails,yhirano55/rails,arjes/rails,illacceptanything/illacceptanything,EmmaB/rails-1,alecspopa/rails,kaspth/rails,tijwelch/rails,rossta/rails,EmmaB/rails-1,EmmaB/rails-1,ngpestelos/rails,tijwelch/rails,lcreid/rails,MSP-Greg/rails,bradleypriest/rails,bolek/rails,Edouard-chin/rails,iainbeeston/rails,mtsmfm/railstest,tgxworld/rails,kaspth/rails,jeremy/rails,kenta-s/rails,Vasfed/rails,Edouard-chin/rails,yawboakye/rails,samphilipd/rails,notapatch/rails,marklocklear/rails,gfvcastro/rails,ttanimichi/rails,Erol/rails,Erol/rails,fabianoleittes/rails,Stellenticket/rails,illacceptanything/illacceptanything,flanger001/rails,mechanicles/rails,yahonda/rails,fabianoleittes/rails,brchristian/rails,gavingmiller/rails,sergey-alekseev/rails,printercu/rails,fabianoleittes/rails,BlakeWilliams/rails,stefanmb/rails,gauravtiwari/rails,deraru/rails,gcourtemanche/rails,rbhitchcock/rails,arunagw/rails,betesh/rails,starknx/rails,rafaelfranca/omg-rails,kmcphillips/rails,shioyama/rails,samphilipd/rails,richseviora/rails,prathamesh-sonpatki/rails,mechanicles/rails,assain/rails,lucasmazza/rails,illacceptanything/illacceptanything,xlymian/rails,shioyama/rails,kamipo/rails,sealocal/rails,MSP-Greg/rails,illacceptanything/illacceptanything,riseshia/railsguides.kr,voray/rails,bogdanvlviv/rails,voray/rails,betesh/rails,kmayer/rails,voray/rails,Vasfed/rails,kmayer/rails,pvalena/rails,prathamesh-sonpatki/rails,Spin42/rails,illacceptanything/illacceptanything,bogdanvlviv/rails,rbhitchcock/rails,kamipo/rails,esparta/rails,kaspth/rails,Stellenticket/rails,kirs/rails-1,kmcphillips/rails,BlakeWilliams/rails,kirs/rails-1,alecspopa/rails,Envek/rails,yalab/rails,pvalena/rails,mijoharas/rails,gauravtiwari/rails,yasslab/railsguid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