Change Result#each to return an Enumerator when called without a block.

As with #10992, this lets us call #with_index, etc on the results.

activerecord/CHANGELOG.md

@@ -1,3 +1,8 @@
+*   `ActiveRecord::Result.each` now returns an `Enumerator` when called without
+     a block, so that it can be chained with other `Enumerable` methods.
+
+    *Ben Woosley*
+
 *   Fixture setup does no longer depend on `ActiveRecord::Base.configurations`.
     This is relevant when `ENV["DATABASE_URL"]` is used in place of a `database.yml`.
 

activerecord/lib/active_record/result.rb

@@ -18,7 +18,11 @@ module ActiveRecord
     end
 
     def each
-      hash_rows.each { |row| yield row }
+      if block_given?
+        hash_rows.each { |row| yield row }
+      else
+        hash_rows.to_enum
+      end
     end
 
     def to_hash

activerecord/test/cases/result_test.rb

@@ -0,0 +1,33 @@
+require "cases/helper"
+
+module ActiveRecord
+  class ResultTest < ActiveRecord::TestCase
+
+    def result
+      Result.new(['col_1', 'col_2'], [
+        ['row 1 col 1', 'row 1 col 2'],
+        ['row 2 col 1', 'row 2 col 2']
+      ])
+    end
+
+    def test_to_hash_returns_row_hashes
+      assert_equal [
+        {'col_1' => 'row 1 col 1', 'col_2' => 'row 1 col 2'},
+        {'col_1' => 'row 2 col 1', 'col_2' => 'row 2 col 2'}
+      ], result.to_hash
+    end
+
+    def test_each_with_block_returns_row_hashes
+      result.each do |row|
+        assert_equal ['col_1', 'col_2'], row.keys
+      end
+    end
+
+    def test_each_without_block_returns_an_enumerator
+      result.each.with_index do |row, index|
+        assert_equal ['col_1', 'col_2'], row.keys
+        assert_kind_of Integer, index
+      end
+    end
+  end
+end