Merge pull request #616 from vreuter/feature/609-CellEncoder-from-Show

gnieh · Jun 25, 2024 · b42cfa0 · b42cfa0
2 parents f3a82b0 + 3f35c4c
commit b42cfa0
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Showing 2 changed files with 15 additions and 1 deletion.
diff --git a/csv/shared/src/main/scala/fs2/data/csv/CellEncoder.scala b/csv/shared/src/main/scala/fs2/data/csv/CellEncoder.scala
@@ -58,6 +58,9 @@ object CellEncoder
   @inline
   def fromToString[A]: CellEncoder[A] = _.toString
 
+  @inline
+  def fromShow[A](implicit ev: Show[A]): CellEncoder[A] = instance(ev.show)
+
   // Primitives
   implicit val unitEncoder: CellEncoder[Unit] = _ => ""
   implicit val booleanEncoder: CellEncoder[Boolean] = fromToString(_)

diff --git a/csv/shared/src/test/scala/fs2/data/csv/CellEncoderTest.scala b/csv/shared/src/test/scala/fs2/data/csv/CellEncoderTest.scala
@@ -22,6 +22,8 @@ import weaver._
 
 import scala.concurrent.duration._
 
+import cats.Show
+
 object CellEncoderTest extends SimpleIOSuite {
 
   // CellEncoder should have implicit instances available for standard types
@@ -53,7 +55,7 @@ object CellEncoderTest extends SimpleIOSuite {
   CellEncoder[java.time.ZoneId]
   CellEncoder[java.time.ZoneOffset]
 
-  pureTest("CellEncoder should decode standard types correctly") {
+  pureTest("CellEncoder should encode standard types correctly") {
     expect(CellEncoder[Unit].apply(()) == "") and
       expect(CellEncoder[Int].apply(78) == "78") and
       expect(CellEncoder[Boolean].apply(true) == "true") and
@@ -73,4 +75,13 @@ object CellEncoderTest extends SimpleIOSuite {
           .apply(java.time.LocalTime.of(13, 4, 29)) == "13:04:29")
   }
 
+  pureTest("CellEncoder instance can be built from native cats.Show instance") {
+    expect(CellEncoder.fromShow[Double].apply(3.54) == "3.54")
+  }
+
+  pureTest("CellEncoder instance can be built from local cats.Show instance") {
+    implicit val showInt42: Show[Int] = Show.show(_ => "42")
+    expect(CellEncoder.fromShow[Int].apply(78) == "42")
+  }
+
 }