Add support for diffing ActiveRecord::Relation objects

Author: mcmire

lib/super_diff.rb

@@ -9,13 +9,14 @@ module SuperDiff
   autoload :DiffFormatters, "super_diff/diff_formatters"
   autoload :Differ, "super_diff/differ"
   autoload :Differs, "super_diff/differs"
+  autoload :EqualityMatcher, "super_diff/equality_matcher"
+  autoload :EqualityMatchers, "super_diff/equality_matchers"
+  autoload :Helpers, "super_diff/helpers"
+  autoload :NoDifferAvailableError, "super_diff/no_differ_available_error"
   autoload(
     :NoOperationalSequencerAvailableError,
     "super_diff/no_operational_sequencer_available_error",
   )
-  autoload :EqualityMatcher, "super_diff/equality_matcher"
-  autoload :EqualityMatchers, "super_diff/equality_matchers"
-  autoload :Helpers, "super_diff/helpers"
   autoload :ObjectInspection, "super_diff/object_inspection"
   autoload :OperationalSequencer, "super_diff/operational_sequencer"
   autoload :OperationalSequencers, "super_diff/operational_sequencers"

lib/super_diff/active_record.rb

@@ -1,20 +1,37 @@
 module SuperDiff
   module ActiveRecord
+    autoload :DiffFormatters, "super_diff/active_record/diff_formatters"
+    autoload :Differs, "super_diff/active_record/differs"
     autoload(
       :ObjectInspection,
       "super_diff/active_record/object_inspection",
     )
     autoload(
-      :OperationalSequencer,
-      "super_diff/active_record/operational_sequencer",
+      :OperationSequences,
+      "super_diff/active_record/operation_sequences",
+    )
+    autoload(
+      :OperationalSequencers,
+      "super_diff/active_record/operational_sequencers",
     )
   end
 end
 
 if defined?(SuperDiff::RSpec)
-  SuperDiff::RSpec.configuration.add_extra_operational_sequencer_class(
-    SuperDiff::ActiveRecord::OperationalSequencer,
-  )
+  SuperDiff::RSpec.configure do |config|
+    config.add_extra_differ_class(
+      SuperDiff::ActiveRecord::Differs::ActiveRecordRelation,
+    )
+    config.add_extra_operational_sequencer_class(
+      SuperDiff::ActiveRecord::OperationalSequencers::ActiveRecordModel,
+    )
+    config.add_extra_operational_sequencer_class(
+      SuperDiff::ActiveRecord::OperationalSequencers::ActiveRecordRelation,
+    )
+    config.add_extra_diff_formatter_class(
+      SuperDiff::ActiveRecord::DiffFormatters::ActiveRecordRelation,
+    )
+  end
 end
 
 SuperDiff::ObjectInspection.map.prepend(

lib/super_diff/active_record/diff_formatters.rb

@@ -0,0 +1,10 @@
+module SuperDiff
+  module ActiveRecord
+    module DiffFormatters
+      autoload(
+        :ActiveRecordRelation,
+        "super_diff/active_record/diff_formatters/active_record_relation",
+      )
+    end
+  end
+end

lib/super_diff/active_record/diff_formatters/active_record_relation.rb

@@ -0,0 +1,23 @@
+module SuperDiff
+  module ActiveRecord
+    module DiffFormatters
+      class ActiveRecordRelation < SuperDiff::DiffFormatters::Base
+        def self.applies_to?(operations)
+          operations.is_a?(OperationSequences::ActiveRecordRelation)
+        end
+
+        def call
+          SuperDiff::DiffFormatters::Collection.call(
+            open_token: "#<ActiveRecord::Relation [",
+            close_token: "]>",
+            collection_prefix: collection_prefix,
+            build_item_prefix: proc { "" },
+            operations: operations,
+            indent_level: indent_level,
+            add_comma: add_comma?,
+          )
+        end
+      end
+    end
+  end
+end

lib/super_diff/active_record/differs.rb

@@ -0,0 +1,10 @@
+module SuperDiff
+  module ActiveRecord
+    module Differs
+      autoload(
+        :ActiveRecordRelation,
+        "super_diff/active_record/differs/active_record_relation",
+      )
+    end
+  end
+end

lib/super_diff/active_record/differs/active_record_relation.rb

@@ -0,0 +1,30 @@
+module SuperDiff
+  module ActiveRecord
+    module Differs
+      class ActiveRecordRelation < SuperDiff::Differs::Base
+        def self.applies_to?(expected, actual)
+          expected.is_a?(::Array) &&
+            actual.is_a?(::ActiveRecord::Relation)
+        end
+
+        def call
+          DiffFormatters::ActiveRecordRelation.call(
+            operations,
+            indent_level: indent_level,
+          )
+        end
+
+        private
+
+        def operations
+          OperationalSequencers::ActiveRecordRelation.call(
+            expected: expected,
+            actual: actual,
+            extra_operational_sequencer_classes: extra_operational_sequencer_classes,
+            extra_diff_formatter_classes: extra_diff_formatter_classes,
+          )
+        end
+      end
+    end
+  end
+end

lib/super_diff/active_record/object_inspection.rb

@@ -2,8 +2,8 @@ module SuperDiff
   module ActiveRecord
     module ObjectInspection
       autoload(
-        :Inspector,
-        "super_diff/active_record/object_inspection/inspector",
+        :Inspectors,
+        "super_diff/active_record/object_inspection/inspectors",
       )
       autoload(
         :MapExtension,

lib/super_diff/active_record/object_inspection/inspector.rb

@@ -0,0 +1,16 @@
+module SuperDiff
+  module ActiveRecord
+    module ObjectInspection
+      module Inspectors
+        autoload(
+          :ActiveRecordModel,
+          "super_diff/active_record/object_inspection/inspectors/active_record_model",
+        )
+        autoload(
+          :ActiveRecordRelation,
+          "super_diff/active_record/object_inspection/inspectors/active_record_relation",
+        )
+      end
+    end
+  end
+end

lib/super_diff/active_record/object_inspection/inspectors.rb

@@ -0,0 +1,38 @@
+module SuperDiff
+  module ActiveRecord
+    module ObjectInspection
+      module Inspectors
+        ActiveRecordModel = SuperDiff::ObjectInspection::InspectionTree.new do
+          add_text do |object|
+            "#<#{object.class} "
+          end
+
+          when_multiline do
+            add_text "{"
+          end
+
+          nested do |object|
+            add_break
+
+            insert_separated_list(
+              ["id"] + (object.attributes.keys.sort - ["id"]),
+              separator: ",",
+            ) do |name|
+              add_text name
+              add_text ": "
+              add_inspection_of object.read_attribute(name)
+            end
+          end
+
+          add_break
+
+          when_multiline do
+            add_text "}"
+          end
+
+          add_text ">"
+        end
+      end
+    end
+  end
+end