Syntax cleanup: for in => each

activerecord/lib/active_record/base.rb

@@ -2018,7 +2018,7 @@ MSG
       def extract_callstack_for_multiparameter_attributes(pairs)
         attributes = { }
 
-        for pair in pairs
+        pairs.each do |pair|
           multiparameter_name, value = pair
           attribute_name = multiparameter_name.split("(").first
           attributes[attribute_name] = {} unless attributes.include?(attribute_name)

activerecord/lib/active_record/relation/finder_methods.rb

@@ -226,7 +226,7 @@ module ActiveRecord
     end
 
     def apply_join_dependency(relation, join_dependency)
-      for association in join_dependency.join_associations
+      join_dependency.join_associations.each do |association|
         relation = association.join_relation(relation)
       end
 

activerecord/lib/active_record/serialization.rb

@@ -37,7 +37,7 @@ module ActiveRecord #:nodoc:
         include_has_options = include_associations.is_a?(Hash)
         associations = include_has_options ? include_associations.keys : Array.wrap(include_associations)
 
-        for association in associations
+        associations.each do |association|
           records = case self.class.reflect_on_association(association).macro
           when :has_many, :has_and_belongs_to_many
             send(association).to_a