test cats vs algebird implicits, fix #142

build.sbt

@@ -19,6 +19,7 @@ description := "A collection of Magnolia add-on modules"
 
 val magnoliaVersion = "0.17.0"
 
+val algebirdVersion = "0.13.7"
 val avroVersion = Option(sys.props("avro.version")).getOrElse("1.10.1")
 val bigqueryVersion = "v2-rev20210215-1.31.0"
 val bigtableVersion = "1.20.1"
@@ -189,7 +190,8 @@ lazy val cats: Project = project
     description := "Magnolia add-on for Cats",
     libraryDependencies ++= Seq(
       "org.typelevel" %% "cats-core" % catsVersion,
-      "org.typelevel" %% "cats-laws" % catsVersion % Test
+      "org.typelevel" %% "cats-laws" % catsVersion % Test,
+      "com.twitter" %% "algebird-core" % algebirdVersion % Test
     )
   )
   .dependsOn(

cats/src/test/scala/magnolify/cats/test/AlgebirdSuite.scala

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2021 Spotify AB.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package magnolify.cats.test
+
+import cats._
+import com.twitter.algebird.{Semigroup => _, _}
+import magnolify.cats.auto._
+import magnolify.test._
+
+import scala.reflect.ClassTag
+
+class AlgebirdSuite extends MagnolifySuite {
+  private def test[T: ClassTag](x: T, y: T, expected: T)(implicit sg: Semigroup[T]): Unit =
+    test(className[T]) {
+      assertEquals(sg.combine(x, y), expected)
+    }
+
+  test(Min(0), Min(1), Min(0))
+  test(Max(0), Max(1), Max(1))
+}