Setup case class derivation compatibility sandbox

.gitignore

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+.bsp
+.metals
+.vscode
+target/

.scalafmt.conf

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+version = "3.6.1"
+runner.dialect = scala213

app/src/main/scala/App.scala

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+import cats.syntax.all._
+import PersonSemigroup._
+
+object App {
+  def main(args: Array[String]): Unit = {
+    println(Person("foo", 2) |+| Person("bar", 3))
+  }
+}

build.sbt

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+ThisBuild / scalaVersion := "3.2.2"
+ThisBuild / crossScalaVersions := Seq("2.13.10", "3.2.2")
+
+lazy val personOld = project
+lazy val personNew = project.settings(
+  mimaPreviousClassfiles := Map(
+    projectID.value -> (personOld / Compile / classDirectory).value
+  ),
+  mimaReportBinaryIssues :=
+    mimaReportBinaryIssues
+      .dependsOn(personOld / Compile / compile)
+      .value
+)
+
+lazy val lib = project
+  .settings(
+    libraryDependencies += "org.typelevel" %% "kittens" % "3.0.0"
+  )
+  .dependsOn(personOld % Provided)
+
+val app = project.dependsOn(lib, personNew)

lib/src/main/scala/PersonSemigroup.scala

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+import cats._
+import cats.derived._
+
+object PersonSemigroup {
+  implicit def instance: Semigroup[Person] = semiauto.semigroup
+}

personNew/src/main/scala/Person.scala

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+case class Person private (name: String, age: Int) {
+  def this(name: String) = this(name, -1)
+
+  def withName(name: String): Person = copy(name = name)
+  def withAge(age: Int): Person = copy(age = age)
+
+  private def copy(name: String = this.name, age: Int = this.age): Person =
+    new Person(name, age)
+}
+
+object Person {
+  def apply(name: String, age: Int): Person = new Person(name, age)
+
+  def apply(name: String): Person = new Person(name)
+
+  private def unapply(person: Person): Some[Person] = Some(person)
+}

personOld/src/main/scala/Person.scala

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+case class Person private (name: String) {
+  def withName(name: String): Person = copy(name = name)
+
+  private def copy(name: String = this.name): Person =
+    new Person(name)
+}
+
+object Person {
+  def apply(name: String): Person = new Person(name)
+  private def unapply(person: Person): Some[Person] = Some(person)
+}

project/build.properties

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+sbt.version=1.8.2

project/plugins.sbt

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+addSbtPlugin("com.typesafe" % "sbt-mima-plugin" % "1.1.2")