Merge branch 'master' into unlock-minitest

6 files changed, 54 insertions, 31 deletions

diff --git a/activerecord/lib/active_record/relation/batches.rb b/activerecord/lib/active_record/relation/batches.rb
index 76031515fd..13a2c3f511 100644
--- a/activerecord/lib/active_record/relation/batches.rb
+++ b/activerecord/lib/active_record/relation/batches.rb
@@ -30,14 +30,14 @@ module ActiveRecord
     #   end
     #
     # ==== Options
-    # * <tt>:batch_size</tt> - Specifies the size of the batch. Default to 1000.
+    # * <tt>:batch_size</tt> - Specifies the size of the batch. Defaults to 1000.
     # * <tt>:start</tt> - Specifies the primary key value to start from, inclusive of the value.
     # * <tt>:finish</tt> - Specifies the primary key value to end at, inclusive of the value.
     # * <tt>:error_on_ignore</tt> - Overrides the application config to specify if an error should be raised when
-    #                               an order is present in the relation.
+    #   an order is present in the relation.
     #
     # Limits are honored, and if present there is no requirement for the batch
-    # size, it can be less than, equal, or greater than the limit.
+    # size: it can be less than, equal to, or greater than the limit.
     #
     # The options +start+ and +finish+ are especially useful if you want
     # multiple workers dealing with the same processing queue. You can make
@@ -89,14 +89,14 @@ module ActiveRecord
     # To be yielded each record one by one, use #find_each instead.
     #
     # ==== Options
-    # * <tt>:batch_size</tt> - Specifies the size of the batch. Default to 1000.
+    # * <tt>:batch_size</tt> - Specifies the size of the batch. Defaults to 1000.
     # * <tt>:start</tt> - Specifies the primary key value to start from, inclusive of the value.
     # * <tt>:finish</tt> - Specifies the primary key value to end at, inclusive of the value.
     # * <tt>:error_on_ignore</tt> - Overrides the application config to specify if an error should be raised when
-    #                               an order is present in the relation.
+    #   an order is present in the relation.
     #
     # Limits are honored, and if present there is no requirement for the batch
-    # size, it can be less than, equal, or greater than the limit.
+    # size: it can be less than, equal to, or greater than the limit.
     #
     # The options +start+ and +finish+ are especially useful if you want
     # multiple workers dealing with the same processing queue. You can make
@@ -140,9 +140,9 @@ module ActiveRecord
     # If you do not provide a block to #in_batches, it will return a
     # BatchEnumerator which is enumerable.
     #
-    #   Person.in_batches.with_index do |relation, batch_index|
+    #   Person.in_batches.each_with_index do |relation, batch_index|
     #     puts "Processing relation ##{batch_index}"
-    #     relation.each { |relation| relation.delete_all }
+    #     relation.delete_all
     #   end
     #
     # Examples of calling methods on the returned BatchEnumerator object:
@@ -152,12 +152,12 @@ module ActiveRecord
     #   Person.in_batches.each_record(&:party_all_night!)
     #
     # ==== Options
-    # * <tt>:of</tt> - Specifies the size of the batch. Default to 1000.
-    # * <tt>:load</tt> - Specifies if the relation should be loaded. Default to false.
+    # * <tt>:of</tt> - Specifies the size of the batch. Defaults to 1000.
+    # * <tt>:load</tt> - Specifies if the relation should be loaded. Defaults to false.
     # * <tt>:start</tt> - Specifies the primary key value to start from, inclusive of the value.
     # * <tt>:finish</tt> - Specifies the primary key value to end at, inclusive of the value.
     # * <tt>:error_on_ignore</tt> - Overrides the application config to specify if an error should be raised when
-    #                               an order is present in the relation.
+    #   an order is present in the relation.
     #
     # Limits are honored, and if present there is no requirement for the batch
     # size, it can be less than, equal, or greater than the limit.
@@ -186,7 +186,7 @@ module ActiveRecord
     #
     # NOTE: It's not possible to set the order. That is automatically set to
     # ascending on the primary key ("id ASC") to make the batch ordering
-    # consistent. Therefore the primary key must be orderable, e.g an integer
+    # consistent. Therefore the primary key must be orderable, e.g. an integer
     # or a string.
     #
     # NOTE: By its nature, batch processing is subject to race conditions if
diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb
index 9cabd1af13..c562f214c9 100644
--- a/activerecord/lib/active_record/relation/calculations.rb
+++ b/activerecord/lib/active_record/relation/calculations.rb
@@ -37,7 +37,16 @@ module ActiveRecord
     # Note: not all valid {Relation#select}[rdoc-ref:QueryMethods#select] expressions are valid #count expressions. The specifics differ
     # between databases. In invalid cases, an error from the database is thrown.
     def count(column_name = nil)
-      return super() if block_given?
+      if block_given?
+        unless column_name.nil?
+          ActiveSupport::Deprecation.warn \
+            "When `count' is called with a block, it ignores other arguments. " \
+            "This behavior is now deprecated and will result in an ArgumentError in Rails 5.3."
+        end
+
+        return super()
+      end
+
       calculate(:count, column_name)
     end
 
@@ -73,7 +82,16 @@ module ActiveRecord
     #
     #   Person.sum(:age) # => 4562
     def sum(column_name = nil)
-      return super() if block_given?
+      if block_given?
+        unless column_name.nil?
+          ActiveSupport::Deprecation.warn \
+            "When `sum' is called with a block, it ignores other arguments. " \
+            "This behavior is now deprecated and will result in an ArgumentError in Rails 5.3."
+        end
+
+        return super()
+      end
+
       calculate(:sum, column_name)
     end
 
@@ -368,9 +386,8 @@ module ActiveRecord
         relation.select_values = [aliased_column]
         subquery = relation.arel.as(subquery_alias)
 
-        sm = Arel::SelectManager.new relation.engine
         select_value = operation_over_aggregate_column(column_alias, "count", distinct)
-        sm.project(select_value).from(subquery)
+        Arel::SelectManager.new(subquery).project(select_value)
       end
   end
 end
diff --git a/activerecord/lib/active_record/relation/delegation.rb b/activerecord/lib/active_record/relation/delegation.rb
index 257ae04ff4..4f739a0415 100644
--- a/activerecord/lib/active_record/relation/delegation.rb
+++ b/activerecord/lib/active_record/relation/delegation.rb
@@ -46,6 +46,8 @@ module ActiveRecord
     delegate :table_name, :quoted_table_name, :primary_key, :quoted_primary_key,
              :connection, :columns_hash, to: :klass
 
+    delegate :ast, :locked, to: :arel
+
     module ClassSpecificRelation # :nodoc:
       extend ActiveSupport::Concern
 
diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb
index a1459c87c6..1d661fa8ed 100644
--- a/activerecord/lib/active_record/relation/finder_methods.rb
+++ b/activerecord/lib/active_record/relation/finder_methods.rb
@@ -307,9 +307,11 @@ module ActiveRecord
         MSG
       end
 
-      return false if !conditions
+      return false if !conditions || limit_value == 0
+
+      relation = self unless eager_loading?
+      relation ||= apply_join_dependency(self, construct_join_dependency(eager_loading: false))
 
-      relation = apply_join_dependency(self, construct_join_dependency(eager_loading: false))
       return false if ActiveRecord::NullRelation === relation
 
       relation = construct_relation_for_exists(relation, conditions)
diff --git a/activerecord/lib/active_record/relation/predicate_builder.rb b/activerecord/lib/active_record/relation/predicate_builder.rb
index 183fe91c05..a6309e0b5c 100644
--- a/activerecord/lib/active_record/relation/predicate_builder.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder.rb
@@ -1,12 +1,3 @@
-require "active_record/relation/predicate_builder/array_handler"
-require "active_record/relation/predicate_builder/base_handler"
-require "active_record/relation/predicate_builder/basic_object_handler"
-require "active_record/relation/predicate_builder/range_handler"
-require "active_record/relation/predicate_builder/relation_handler"
-
-require "active_record/relation/predicate_builder/association_query_value"
-require "active_record/relation/predicate_builder/polymorphic_array_value"
-
 module ActiveRecord
   class PredicateBuilder # :nodoc:
     delegate :resolve_column_aliases, to: :table
@@ -178,3 +169,12 @@ module ActiveRecord
       end
   end
 end
+
+require "active_record/relation/predicate_builder/array_handler"
+require "active_record/relation/predicate_builder/base_handler"
+require "active_record/relation/predicate_builder/basic_object_handler"
+require "active_record/relation/predicate_builder/range_handler"
+require "active_record/relation/predicate_builder/relation_handler"
+
+require "active_record/relation/predicate_builder/association_query_value"
+require "active_record/relation/predicate_builder/polymorphic_array_value"
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 1178dec706..79e65baae5 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -248,7 +248,7 @@ module ActiveRecord
         return super()
       end
 
-      raise ArgumentError, "Call this with at least one field" if fields.empty?
+      raise ArgumentError, "Call `select' with at least one field" if fields.empty?
       spawn._select!(*fields)
     end
 
@@ -1100,14 +1100,16 @@ module ActiveRecord
       end
 
       VALID_DIRECTIONS = [:asc, :desc, :ASC, :DESC,
-                          "asc", "desc", "ASC", "DESC"] # :nodoc:
+                          "asc", "desc", "ASC", "DESC"].to_set # :nodoc:
 
       def validate_order_args(args)
         args.each do |arg|
           next unless arg.is_a?(Hash)
           arg.each do |_key, value|
-            raise ArgumentError, "Direction \"#{value}\" is invalid. Valid " \
-                                 "directions are: #{VALID_DIRECTIONS.inspect}" unless VALID_DIRECTIONS.include?(value)
+            unless VALID_DIRECTIONS.include?(value)
+              raise ArgumentError,
+                "Direction \"#{value}\" is invalid. Valid directions are: #{VALID_DIRECTIONS.to_a.inspect}"
+            end
           end
         end
       end