Merge branch 'master' into adequaterecord

* master: (311 commits)
  Add a missing changelog entry for #13981 and #14035
  Revert "Fixed plugin_generator test"
  implements new option :month_format_string for date select helpers [Closes #13618]
  add factory methods for empty alias trackers
  guarantee a list in the alias tracker so we can remove a conditional
  stop exposing table_joins
  make most parameters to the AliasTracker required
  make a singleton for AssociationScope
  pass the association and connection to the scope method
  pass the tracker down the stack and construct it in the scope method
  clean up add_constraints signature
  remove the reflection delegate
  remove klass delegator
  remove railties changes. fixes #14054
  remove chain delegate
  remove scope_chain delegate
  Add verb to sanitization note
  fix path shown in mailer's templates
  updated Travis build status image url
  fix guide active_support_core_extensions. add Note to String#indent [ci skip]
  ...

Conflicts:
	activerecord/lib/active_record/associations/join_dependency.rb
	activerecord/test/cases/associations/association_scope_test.rb

1 files changed, 29 insertions, 2 deletions

diff --git a/activemodel/CHANGELOG.md b/activemodel/CHANGELOG.md
index 09fdd84844..500d8dc42f 100644
--- a/activemodel/CHANGELOG.md
+++ b/activemodel/CHANGELOG.md
@@ -1,6 +1,33 @@
-*   `attribute_changed?` now accepts parameters which check the old and new value of the attribute
+*   `#to_param` returns `nil` if `#to_key` returns `nil`. Fixes #11399.
 
-    `model.name_changed?(from: "Pete", to: "Ringo")`
+    *Yves Senn*
+
+*   Ability to specify multiple contexts when defining a validation.
+
+    Example:
+
+        class Person
+          include ActiveModel::Validations
+
+          attr_reader :name
+          validates_presence_of :name, on: [:verify, :approve]
+        end
+
+        person = Person.new
+        person.valid?                           # => true
+        person.valid?(:verify)                  # => false
+        person.errors.full_messages_for(:name)  # => ["Name can't be blank"]
+        person.valid?(:approve)                 # => false
+        person.errors.full_messages_for(:name)  # => ["Name can't be blank"]
+
+    *Vince Puzzella*
+
+*   `attribute_changed?` now accepts a hash to check if the attribute was
+    changed `:from` and/or `:to` a given value.
+
+    Example:
+
+        model.name_changed?(from: "Pete", to: "Ringo")
 
     *Tejas Dinkar*