Merge pull request planetscale#5 from planetscale/kaminari-without-count

Make compatible with Kaminari without_count

lib/fast_page/active_record_methods.rb

@@ -6,10 +6,20 @@ def deferred_join_load
       # Must have a limit or offset defined
       raise ArgumentError, "You must specify a limit or offset to use fast_page" if !limit_value && !offset_value
 
+      # We load 1 additional record to determine if there is a next page.
+      # This helps us avoid doing a count over all records
+      @values[:limit] = limit_value + 1 if limit_value
       id_scope = dup
       id_scope = id_scope.except(:includes) unless references_eager_loaded_tables?
       ids = id_scope.pluck(:id)
 
+      if limit_value
+        @values[:limit] = limit_value - 1
+        # Record if there is a next page
+        @_has_next = ids.length > limit_value
+        ids = ids.first(limit_value)
+      end
+
       if ids.empty?
         @records = []
         @loaded = true

test/fast_page_test.rb

@@ -71,7 +71,8 @@ def test_returns_same_results
     og = User.all.limit(5).offset(5).order(created_at: :desc)
     fast = User.all.limit(5).offset(5).order(created_at: :desc).fast_page
 
-    assert_equal og, fast
+    assert_equal og.length, fast.length
+    assert_equal og.select(&:id), fast.select(&:id)
   end
 
   def test_errors_without_limit_or_offset
@@ -84,7 +85,8 @@ def test_works_limit_only
     og = User.all.limit(5).order(created_at: :desc)
     fast = User.all.limit(5).order(created_at: :desc).fast_page
 
-    assert_equal og, fast
+    assert_equal og.length, fast.length
+    assert_equal og.select(&:id), fast.select(&:id)
   end
 
   def test_works_offset_only

test/kaminari_test.rb

@@ -26,7 +26,19 @@ def test_kaminari_works
     og_page = User.page(2).per(1).order(created_at: :desc)
     fast_page = User.page(2).per(1).order(created_at: :desc).fast_page
 
-    assert_equal og_page, fast_page
+    assert_equal og_page.length, fast_page.length
+    assert_equal og_page.first.id, fast_page.first.id
+    assert_equal og_page.current_page, fast_page.current_page
+    assert_equal og_page.next_page, fast_page.next_page
+    assert_equal og_page.prev_page, fast_page.prev_page
+  end
+
+  def test_kaminari_works_without_count
+    og_page = User.page(2).per(1).order(created_at: :desc).without_count
+    fast_page = User.page(2).per(1).order(created_at: :desc).without_count.fast_page
+
+    assert_equal og_page.length, fast_page.length
+    assert_equal og_page.first.id, fast_page.first.id
     assert_equal og_page.current_page, fast_page.current_page
     assert_equal og_page.next_page, fast_page.next_page
     assert_equal og_page.prev_page, fast_page.prev_page