Add readers and writers instances for cats non-empty collections

build.sbt

@@ -9,7 +9,7 @@ lazy val scala3 = "3.3.0"
 ThisBuild / scalaVersion := scala3
 
 lazy val commonSettings = Seq(
-  version := "0.28.2",
+  version := "0.28.4",
   organization := "com.tethys-json",
   licenses := Seq("Apache-2.0" -> url("https://www.apache.org/licenses/LICENSE-2.0")),
   homepage := Some(url("https://github.com/tethys-json/tethys")),
@@ -86,7 +86,7 @@ lazy val tethys = project.in(file("."))
     crossScalaVersions := Seq.empty,
     commonSettings
   )
-  .aggregate(core, `macro-derivation`, `jackson-211`, `jackson-212`, `jackson-213`, json4s, circe, refined, enumeratum)
+  .aggregate(core, `macro-derivation`, `jackson-211`, `jackson-212`, `jackson-213`, json4s, circe, refined, enumeratum, cats)
 
 lazy val modules = file("modules")
 
@@ -106,6 +106,18 @@ lazy val core = project.in(modules / "core")
     libraryDependencies ++= addScalaReflect(scalaVersion.value)
   )
 
+lazy val cats = project.in(modules / "cats")
+  .settings(crossScalaSettings)
+  .settings(commonSettings)
+  .settings(testSettings)
+  .settings(
+    name := "tethys-cats",
+    libraryDependencies ++= Seq(
+      "org.typelevel" %% "cats-core" % "2.10.0",
+    )
+  )
+  .dependsOn(core)
+
 lazy val `macro-derivation` = project.in(modules / "macro-derivation")
   .settings(crossScalaSettings)
   .settings(commonSettings)

modules/cats/src/main/scala-2.12/tethys/cats/NonEmptySetReader.scala

@@ -0,0 +1,26 @@
+package tethys.cats
+
+import cats.data.NonEmptySet
+import tethys.JsonReader
+import tethys.readers.{FieldName, ReaderError}
+import tethys.readers.tokens.TokenIterator
+
+import scala.collection.immutable.{Seq, SortedSet}
+
+trait NonEmptySetReader {
+
+  implicit def readerForNes[T: JsonReader: Ordering]
+      : JsonReader[NonEmptySet[T]] =
+    new JsonReader[NonEmptySet[T]] {
+      override def read(
+          it: TokenIterator
+      )(implicit fieldName: FieldName): NonEmptySet[T] =
+        NonEmptySet.fromSet(SortedSet(JsonReader[Seq[T]].read(it): _*)) match {
+          case Some(value) => value
+          case None =>
+            ReaderError.wrongJson(
+              s"Seq is empty and can't be converted to NonEmptySet"
+            )
+        }
+    }
+}

modules/cats/src/main/scala-2.13+/tethys/cats/NonEmptySetReader.scala

@@ -0,0 +1,26 @@
+package tethys.cats
+
+import cats.data.NonEmptySet
+import tethys.JsonReader
+import tethys.readers.{FieldName, ReaderError}
+import tethys.readers.tokens.TokenIterator
+
+import scala.collection.immutable.SortedSet
+
+trait NonEmptySetReader {
+
+  implicit def readerForNes[T: JsonReader: Ordering]
+      : JsonReader[NonEmptySet[T]] =
+    new JsonReader[NonEmptySet[T]] {
+      override def read(
+          it: TokenIterator
+      )(implicit fieldName: FieldName): NonEmptySet[T] =
+        NonEmptySet.fromSet(SortedSet.from(JsonReader[Seq[T]].read(it))) match {
+          case Some(value) => value
+          case None =>
+            ReaderError.wrongJson(
+              s"Seq is empty and can't be converted to NonEmptySet"
+            )
+        }
+    }
+}

modules/cats/src/main/scala-3/tethys.cats/NonEmptySetReader.scala

@@ -0,0 +1,26 @@
+package tethys.cats
+
+import cats.data.NonEmptySet
+import tethys.JsonReader
+import tethys.readers.{FieldName, ReaderError}
+import tethys.readers.tokens.TokenIterator
+
+import scala.collection.immutable.SortedSet
+
+trait NonEmptySetReader {
+
+  implicit def readerForNes[T: JsonReader: Ordering]
+      : JsonReader[NonEmptySet[T]] =
+    new JsonReader[NonEmptySet[T]] {
+      override def read(
+          it: TokenIterator
+      )(implicit fieldName: FieldName): NonEmptySet[T] =
+        NonEmptySet.fromSet(SortedSet.from(JsonReader[Seq[T]].read(it))) match {
+          case Some(value) => value
+          case None =>
+            ReaderError.wrongJson(
+              s"Seq is empty and can't be converted to NonEmptySet"
+            )
+        }
+    }
+}

modules/cats/src/main/scala/tethys/cats/instances.scala

@@ -0,0 +1,6 @@
+package tethys.cats
+
+import tethys.cats.readers.CatsReaders
+import tethys.cats.writers.CatsWriters
+
+object instances extends CatsReaders with CatsWriters with NonEmptySetReader

modules/cats/src/main/scala/tethys/cats/readers/CatsReaders.scala

@@ -0,0 +1,56 @@
+package tethys.cats.readers
+
+import cats.data._
+import tethys.readers.tokens.TokenIterator
+import tethys.readers.{FieldName, ReaderError}
+import tethys.JsonReader
+import tethys.JsonReader.iterableReader
+
+trait CatsReaders {
+
+  implicit def readerForNel[T: JsonReader]: JsonReader[NonEmptyList[T]] =
+    new JsonReader[NonEmptyList[T]] {
+      override def read(
+          it: TokenIterator
+      )(implicit fieldName: FieldName): NonEmptyList[T] =
+        NonEmptyList.fromList(JsonReader[List[T]].read(it)) match {
+          case Some(value) => value
+          case None =>
+            ReaderError.wrongJson(
+              s"List is empty and can't be converted to NonEmptyList"
+            )
+        }
+    }
+
+  implicit def readerForNev[T: JsonReader]: JsonReader[NonEmptyVector[T]] =
+    new JsonReader[NonEmptyVector[T]] {
+      override def read(
+          it: TokenIterator
+      )(implicit fieldName: FieldName): NonEmptyVector[T] =
+        NonEmptyVector.fromVector(JsonReader[Vector[T]].read(it)) match {
+          case Some(value) => value
+          case None =>
+            ReaderError.wrongJson(
+              s"Vector is empty and can't be converted to NonEmptyVector"
+            )
+        }
+    }
+
+  implicit def readerForChain[T: JsonReader]: JsonReader[Chain[T]] =
+    JsonReader[Seq[T]].map(Chain.fromIterableOnce)
+
+  implicit def readerForNec[T: JsonReader]: JsonReader[NonEmptyChain[T]] =
+    new JsonReader[NonEmptyChain[T]] {
+      override def read(
+          it: TokenIterator
+      )(implicit fieldName: FieldName): NonEmptyChain[T] =
+        NonEmptyChain.fromChain(JsonReader[Chain[T]].read(it)) match {
+          case Some(value) => value
+          case None =>
+            ReaderError.wrongJson(
+              s"Chain is empty and can't be converted to NonEmptyChain"
+            )
+        }
+    }
+
+}

modules/cats/src/main/scala/tethys/cats/writers/CatsWriters.scala

@@ -0,0 +1,21 @@
+package tethys.cats.writers
+
+import cats.data._
+import tethys.JsonWriter
+
+trait CatsWriters {
+  implicit def writerForNev[T: JsonWriter]: JsonWriter[NonEmptyVector[T]] =
+    JsonWriter[Vector[T]].contramap(_.toVector)
+
+  implicit def writerForNel[T: JsonWriter]: JsonWriter[NonEmptyList[T]] =
+    JsonWriter[List[T]].contramap(_.toList)
+
+  implicit def writerForNes[T: JsonWriter]: JsonWriter[NonEmptySet[T]] =
+    JsonWriter[Set[T]].contramap(_.toSortedSet)
+
+  implicit def writerForChain[T: JsonWriter]: JsonWriter[Chain[T]] =
+    JsonWriter[List[T]].contramap(_.toList)
+
+  implicit def writerForNec[T: JsonWriter]: JsonWriter[NonEmptyChain[T]] =
+    JsonWriter[Chain[T]].contramap(_.toChain)
+}

modules/cats/src/test/scala/tethys/cats/CatsSupportTests.scala

@@ -0,0 +1,44 @@
+package tethys.cats
+
+import cats.data._
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
+import tethys.commons.TokenNode._
+import instances._
+import tethys.readers.ReaderError
+import tethys.writers.tokens.SimpleTokenWriter._
+
+class CatsSupportTests extends AnyFlatSpec with Matchers {
+  val nev: NonEmptyVector[String] = NonEmptyVector.of("a", "b")
+  val nel: NonEmptyList[Int] = NonEmptyList.of(1, 2)
+  val nes: NonEmptySet[Int] = NonEmptySet.of(1, 2, 3, 4)
+  val chain: Chain[Int] = Chain.fromIterableOnce(Seq(1, 2, 3))
+  val nec: NonEmptyChain[String] = NonEmptyChain.of("a", "b", "c")
+
+  behavior of "CatsWriters"
+  it should "write non-empty" in {
+    nev.asTokenList shouldBe arr("a", "b")
+    nel.asTokenList shouldBe arr(1, 2)
+    nes.asTokenList shouldBe arr(1, 2, 3, 4)
+    chain.asTokenList shouldBe arr(1, 2, 3)
+    nec.asTokenList shouldBe arr("a", "b", "c")
+  }
+
+  behavior of "CatsReaders"
+  it should "read non-empty" in {
+    nev shouldBe arr("a", "b").tokensAs[NonEmptyVector[String]]
+    assertThrows[ReaderError](Nil.tokensAs[NonEmptyVector[String]])
+
+    nel shouldBe arr(1, 2).tokensAs[NonEmptyList[Int]]
+    assertThrows[ReaderError](Nil.tokensAs[NonEmptyList[Int]])
+
+    nes shouldBe arr(1, 2, 3, 4).tokensAs[NonEmptySet[Int]]
+    nes shouldBe arr(4, 4, 1, 3, 3, 2).tokensAs[NonEmptySet[Int]]
+    assertThrows[ReaderError](Nil.tokensAs[NonEmptySet[Int]])
+
+    chain shouldBe arr(1, 2, 3).tokensAs[Chain[Int]]
+
+    nec shouldBe arr("a", "b", "c").tokensAs[NonEmptyChain[String]]
+    assertThrows[ReaderError](Nil.tokensAs[NonEmptyChain[String]])
+  }
+}