Merge pull request #69 from codeclimate/mg-send-slack-snapshot-response

Return hash instead of nil when no changes in snapshot

Author: mrgilman

lib/cc/formatters/snapshot_formatter.rb

@@ -59,6 +59,10 @@ def initialize(payload)
         @improved_constants_payload = data.merge("constants" => improved_constants) if improved_constants.any?
       end
 
+      def changed?
+        alert_constants_payload.present? || improved_constants_payload.present?
+      end
+
     private
 
       def new_constants_selector

lib/cc/services/slack.rb

@@ -23,7 +23,13 @@ def receive_test
   end
 
   def receive_snapshot
-    send_snapshot_to_slack(CC::Formatters::SnapshotFormatter::Base.new(payload))
+    snapshot = CC::Formatters::SnapshotFormatter::Base.new(payload)
+
+    if snapshot.changed?
+      send_snapshot_to_slack(snapshot)
+    else
+      { ok: false, ignored: true, message: "No changes in snapshot" }
+    end
   end
 
   def receive_coverage

test/formatters/snapshot_formatter_test.rb

@@ -44,4 +44,16 @@ def test_snapshot_formatter_test_with_relaxed_constraints
     refute_nil f.alert_constants_payload
     refute_nil f.improved_constants_payload
   end
+
+  def test_changed_when_snapshot_changed
+    f = described_class.new({"new_constants" => [],
+                             "changed_constants" => [{"to" => {"rating" => "A"}, "from" => {"rating" => "D"}}]
+    })
+    assert f.changed?
+  end
+
+  def test_changed_when_no_changes
+    f = described_class.new({"new_constants" => [], "changed_constants" => []})
+    refute f.changed?
+  end
 end

test/slack_test.rb

@@ -184,6 +184,17 @@ def test_receive_test
     assert_equal "Test message sent", response[:message]
   end
 
+  def test_no_changes_in_snapshot
+    data = { "name" => "snapshot", "repo_name" => "Rails",
+             "new_constants" => [],
+             "changed_constants" => [],
+    }
+    response = receive_event(data)
+
+    assert_equal false, response[:ok]
+    assert response[:ignored]
+  end
+
   private
 
   def assert_slack_receives(color, event_data, expected_body)