Revert unused code and re-using query annotation for `update_all` and `delete_all`

This partly reverts #35617.

#35617 includes unused code (for `InsertStatement`) and re-using query
annotation for `update_all` and `delete_all`, which has not been
discussed yet.

If a relation has any annotation, I think it is mostly for SELECT query,
so re-using annotation by default is not always desired behavior for me.

We should discuss about desired behavior before publishing the
implementation.

7 files changed, 11 insertions, 32 deletions

diff --git a/activerecord/lib/arel/nodes/delete_statement.rb b/activerecord/lib/arel/nodes/delete_statement.rb
index 56249b2bad..a419975335 100644
--- a/activerecord/lib/arel/nodes/delete_statement.rb
+++ b/activerecord/lib/arel/nodes/delete_statement.rb
@@ -3,7 +3,7 @@
 module Arel # :nodoc: all
   module Nodes
     class DeleteStatement < Arel::Nodes::Node
-      attr_accessor :left, :right, :orders, :limit, :offset, :key, :comment
+      attr_accessor :left, :right, :orders, :limit, :offset, :key
 
       alias :relation :left
       alias :relation= :left=
@@ -18,18 +18,16 @@ module Arel # :nodoc: all
         @limit = nil
         @offset = nil
         @key = nil
-        @comment = nil
       end
 
       def initialize_copy(other)
         super
         @left  = @left.clone if @left
         @right = @right.clone if @right
-        @comment = @comment.clone if @comment
       end
 
       def hash
-        [self.class, @left, @right, @orders, @limit, @offset, @key, @comment].hash
+        [self.class, @left, @right, @orders, @limit, @offset, @key].hash
       end
 
       def eql?(other)
@@ -39,8 +37,7 @@ module Arel # :nodoc: all
           self.orders == other.orders &&
           self.limit == other.limit &&
           self.offset == other.offset &&
-          self.key == other.key &&
-          self.comment == other.comment
+          self.key == other.key
       end
       alias :== :eql?
     end
diff --git a/activerecord/lib/arel/nodes/insert_statement.rb b/activerecord/lib/arel/nodes/insert_statement.rb
index 8430dd23da..d28fd1f6c8 100644
--- a/activerecord/lib/arel/nodes/insert_statement.rb
+++ b/activerecord/lib/arel/nodes/insert_statement.rb
@@ -3,7 +3,7 @@
 module Arel # :nodoc: all
   module Nodes
     class InsertStatement < Arel::Nodes::Node
-      attr_accessor :relation, :columns, :values, :select, :comment
+      attr_accessor :relation, :columns, :values, :select
 
       def initialize
         super()
@@ -11,7 +11,6 @@ module Arel # :nodoc: all
         @columns  = []
         @values   = nil
         @select   = nil
-        @comment  = nil
       end
 
       def initialize_copy(other)
@@ -19,11 +18,10 @@ module Arel # :nodoc: all
         @columns = @columns.clone
         @values =  @values.clone if @values
         @select =  @select.clone if @select
-        @comment =  @comment.clone if @comment
       end
 
       def hash
-        [@relation, @columns, @values, @select, @comment].hash
+        [@relation, @columns, @values, @select].hash
       end
 
       def eql?(other)
@@ -31,8 +29,7 @@ module Arel # :nodoc: all
           self.relation == other.relation &&
           self.columns == other.columns &&
           self.select == other.select &&
-          self.values == other.values &&
-          self.comment == other.comment
+          self.values == other.values
       end
       alias :== :eql?
     end
diff --git a/activerecord/lib/arel/nodes/select_core.rb b/activerecord/lib/arel/nodes/select_core.rb
index b6154b7ff4..11b4f39ece 100644
--- a/activerecord/lib/arel/nodes/select_core.rb
+++ b/activerecord/lib/arel/nodes/select_core.rb
@@ -40,7 +40,6 @@ module Arel # :nodoc: all
         @groups      = @groups.clone
         @havings     = @havings.clone
         @windows     = @windows.clone
-        @comment     = @comment.clone if @comment
       end
 
       def hash
diff --git a/activerecord/lib/arel/nodes/update_statement.rb b/activerecord/lib/arel/nodes/update_statement.rb
index 015bcd7613..cfaa19e392 100644
--- a/activerecord/lib/arel/nodes/update_statement.rb
+++ b/activerecord/lib/arel/nodes/update_statement.rb
@@ -3,7 +3,7 @@
 module Arel # :nodoc: all
   module Nodes
     class UpdateStatement < Arel::Nodes::Node
-      attr_accessor :relation, :wheres, :values, :orders, :limit, :offset, :key, :comment
+      attr_accessor :relation, :wheres, :values, :orders, :limit, :offset, :key
 
       def initialize
         @relation = nil
@@ -13,18 +13,16 @@ module Arel # :nodoc: all
         @limit    = nil
         @offset   = nil
         @key      = nil
-        @comment  = nil
       end
 
       def initialize_copy(other)
         super
         @wheres = @wheres.clone
         @values = @values.clone
-        @comment = @comment.clone if @comment
       end
 
       def hash
-        [@relation, @wheres, @values, @orders, @limit, @offset, @key, @comment].hash
+        [@relation, @wheres, @values, @orders, @limit, @offset, @key].hash
       end
 
       def eql?(other)
@@ -35,8 +33,7 @@ module Arel # :nodoc: all
           self.orders == other.orders &&
           self.limit == other.limit &&
           self.offset == other.offset &&
-          self.key == other.key &&
-          self.comment == other.comment
+          self.key == other.key
       end
       alias :== :eql?
     end
diff --git a/activerecord/lib/arel/select_manager.rb b/activerecord/lib/arel/select_manager.rb
index 4e9f527235..ddc9e394dd 100644
--- a/activerecord/lib/arel/select_manager.rb
+++ b/activerecord/lib/arel/select_manager.rb
@@ -249,10 +249,6 @@ module Arel # :nodoc: all
       self
     end
 
-    def comment_node
-      @ctx.comment
-    end
-
     private
       def collapse(exprs)
         exprs = exprs.compact
diff --git a/activerecord/lib/arel/tree_manager.rb b/activerecord/lib/arel/tree_manager.rb
index 326c4f995c..0476399618 100644
--- a/activerecord/lib/arel/tree_manager.rb
+++ b/activerecord/lib/arel/tree_manager.rb
@@ -36,11 +36,6 @@ module Arel # :nodoc: all
         @ast.wheres << expr
         self
       end
-
-      def comment(*values)
-        @ast.comment = Nodes::Comment.new(values)
-        self
-      end
     end
 
     attr_reader :ast
diff --git a/activerecord/lib/arel/visitors/to_sql.rb b/activerecord/lib/arel/visitors/to_sql.rb
index 4192d9efdc..277d553e6c 100644
--- a/activerecord/lib/arel/visitors/to_sql.rb
+++ b/activerecord/lib/arel/visitors/to_sql.rb
@@ -35,7 +35,6 @@ module Arel # :nodoc: all
           collect_nodes_for o.wheres, collector, " WHERE ", " AND "
           collect_nodes_for o.orders, collector, " ORDER BY "
           maybe_visit o.limit, collector
-          maybe_visit o.comment, collector
         end
 
         def visit_Arel_Nodes_UpdateStatement(o, collector)
@@ -48,7 +47,6 @@ module Arel # :nodoc: all
           collect_nodes_for o.wheres, collector, " WHERE ", " AND "
           collect_nodes_for o.orders, collector, " ORDER BY "
           maybe_visit o.limit, collector
-          maybe_visit o.comment, collector
         end
 
         def visit_Arel_Nodes_InsertStatement(o, collector)
@@ -64,9 +62,9 @@ module Arel # :nodoc: all
             maybe_visit o.values, collector
           elsif o.select
             maybe_visit o.select, collector
+          else
+            collector
           end
-
-          maybe_visit o.comment, collector
         end
 
         def visit_Arel_Nodes_Exists(o, collector)