Upgrade deps and add Scala 3 support

* Upgrade all deps
* Split sources in scala-2 and scala-3 for required compat changes
* Mostly bincompat, but had to remove a few functions in Resources
  object

.github/workflows/ci.yml

@@ -28,15 +28,21 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        scala: [2.12, 2.13]
+        scala: [2.12, 2.13, 3]
         java: [temurin@11, temurin@17]
         project: [rootJVM]
         exclude:
           - scala: 2.12
             java: temurin@17
+          - scala: 3
+            java: temurin@17
     runs-on: ${{ matrix.os }}
     timeout-minutes: 60
     steps:
+      - name: Install sbt
+        if: contains(runner.os, 'macos')
+        run: brew install sbt
+
       - name: Checkout current branch (full)
         uses: actions/checkout@v4
         with:
@@ -115,6 +121,10 @@ jobs:
         java: [temurin@11]
     runs-on: ${{ matrix.os }}
     steps:
+      - name: Install sbt
+        if: contains(runner.os, 'macos')
+        run: brew install sbt
+
       - name: Checkout current branch (full)
         uses: actions/checkout@v4
         with:
@@ -166,6 +176,16 @@ jobs:
           tar xf targets.tar
           rm targets.tar
 
+      - name: Download target directories (3, rootJVM)
+        uses: actions/download-artifact@v4
+        with:
+          name: target-${{ matrix.os }}-${{ matrix.java }}-3-rootJVM
+
+      - name: Inflate target directories (3, rootJVM)
+        run: |
+          tar xf targets.tar
+          rm targets.tar
+
       - name: Import signing key
         if: env.PGP_SECRET != '' && env.PGP_PASSPHRASE == ''
         env:
@@ -199,6 +219,10 @@ jobs:
         java: [temurin@11]
     runs-on: ${{ matrix.os }}
     steps:
+      - name: Install sbt
+        if: contains(runner.os, 'macos')
+        run: brew install sbt
+
       - name: Checkout current branch (full)
         uses: actions/checkout@v4
         with:
@@ -233,5 +257,5 @@ jobs:
       - name: Submit Dependencies
         uses: scalacenter/sbt-dependency-submission@v2
         with:
-          modules-ignore: rootjs_2.12 rootjs_2.13 rootjvm_2.12 rootjvm_2.13 rootnative_2.12 rootnative_2.13 example1_2.12 example1_2.13
+          modules-ignore: rootjs_2.12 rootjs_2.13 rootjs_3 rootjvm_2.12 rootjvm_2.13 rootjvm_3 rootnative_2.12 rootnative_2.13 rootnative_3 example1_2.12 example1_2.13 example1_3
           configs-ignore: test scala-tool scala-doc-tool test-internal

.gitignore

@@ -10,3 +10,7 @@ target/
 .classpath
 tmp/
 .bsp/
+.metals/
+.vscode/
+.jvm/
+*.semanticdb

.scalafmt.conf

@@ -1,5 +1,5 @@
 version = 3.5.0
-runner.dialect = scala213
+runner.dialect = scala3
 continuationIndent.defnSite = 2
 docstrings.style = Asterisk
 includeCurlyBraceInSelectChains = false
@@ -15,3 +15,9 @@ rewrite.rules = [
   AsciiSortImports,
   PreferCurlyFors
 ]
+
+fileOverride {
+  "glob:**/scala-3/**/*.scala" {
+    runner.dialect = scala3
+  }
+}

build.sbt

@@ -4,14 +4,15 @@ ThisBuild / circeRootOfCodeCoverage := None
 ThisBuild / startYear := Some(2016)
 
 val scala212 = "2.12.19"
-val scala213 = "2.13.11"
+val scala213 = "2.13.14"
+val scala3 = "3.3.3"
 ThisBuild / scalaVersion := scala213
-ThisBuild / crossScalaVersions := Seq(scala212, scala213)
+ThisBuild / crossScalaVersions := Seq(scala212, scala213, scala3)
 
-val circeVersion = "0.14.6"
-val scalacheckVersion = "1.17.0"
-val disciplineScalatestVersion = "2.2.0"
-val scalacheckScalaTestVersion = "3.2.18.0"
+val circeVersion = "0.14.9"
+val scalacheckVersion = "1.18.0"
+val disciplineScalatestVersion = "2.3.0"
+val scalacheckScalaTestVersion = "3.2.19.0"
 
 val root = tlCrossRootProject.aggregate(golden, example1)
 
@@ -21,15 +22,23 @@ lazy val golden = crossProject(JVMPlatform)
   .settings(
     moduleName := "circe-golden",
     libraryDependencies ++= Seq(
-      "org.scalatestplus" %%% "scalacheck-1-17" % scalacheckScalaTestVersion,
+      "org.scalatestplus" %%% "scalacheck-1-18" % scalacheckScalaTestVersion,
       "io.circe" %%% "circe-core" % circeVersion,
       "io.circe" %%% "circe-parser" % circeVersion,
       "io.circe" %%% "circe-testing" % circeVersion,
       "io.circe" %%% "circe-generic" % circeVersion % Test,
       "org.scalacheck" %% "scalacheck" % scalacheckVersion,
-      "org.typelevel" %%% "discipline-scalatest" % disciplineScalatestVersion % Test,
-      scalaOrganization.value % "scala-reflect" % scalaVersion.value % Provided
-    )
+      "org.typelevel" %%% "discipline-scalatest" % disciplineScalatestVersion % Test
+    ),
+    libraryDependencies ++= {
+      if (tlIsScala3.value) Nil
+      else
+        Seq(
+          scalaOrganization.value % "scala-reflect" % scalaVersion.value % Provided
+        )
+    },
+    Test / classLoaderLayeringStrategy := ClassLoaderLayeringStrategy.Flat,
+    tlVersionIntroduced := Map("2.13" -> "0.14.0", "2.12" -> "0.4.0", "3" -> "0.4.1")
   )
 
 lazy val example1 = crossProject(JVMPlatform)

golden/src/main/scala-2/io/circe/testing/golden/GoldenCodecTestsCompanion.scala

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2016 circe
+ *
+ * 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 io.circe.testing.golden
+
+import io.circe.Decoder
+import io.circe.Encoder
+import io.circe.Printer
+import org.scalacheck.Arbitrary
+
+import scala.reflect.runtime.universe.TypeTag
+
+trait GoldenCodecTestsCompanion { self: GoldenCodecTests.type =>
+  def apply[A: Decoder: Encoder: Arbitrary: TypeTag]: GoldenCodecTests[A] =
+    fromLaws[A](ResourceFileGoldenCodecLaws[A]())
+
+  def apply[A: Decoder: Encoder: Arbitrary: TypeTag](printer: Printer): GoldenCodecTests[A] =
+    fromLaws[A](ResourceFileGoldenCodecLaws[A](printer = printer))
+
+  def apply[A: Decoder: Encoder: Arbitrary: TypeTag](count: Int): GoldenCodecTests[A] =
+    fromLaws[A](ResourceFileGoldenCodecLaws[A](count = count))
+
+  def apply[A: Decoder: Encoder: Arbitrary: TypeTag](count: Int, printer: Printer): GoldenCodecTests[A] =
+    fromLaws[A](ResourceFileGoldenCodecLaws[A](count = count, printer = printer))
+
+}

golden/src/main/scala-2/io/circe/testing/golden/ResourceFileGoldenCodecLawsCompanion.scala

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2016 circe
+ *
+ * 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 io.circe.testing.golden
+
+import io.circe.Decoder
+import io.circe.Encoder
+import io.circe.Printer
+import org.scalacheck.Arbitrary
+
+import scala.reflect.runtime.universe.TypeTag
+
+trait ResourceFileGoldenCodecLawsCompanion { self: ResourceFileGoldenCodecLaws.type =>
+
+  def apply[A](
+    size: Int = 100,
+    count: Int = 1,
+    printer: Printer = Printer.spaces2
+  )(implicit
+    decodeA: Decoder[A],
+    encodeA: Encoder[A],
+    arbitraryA: Arbitrary[A],
+    typeTagA: TypeTag[A]
+  ): GoldenCodecLaws[A] =
+    self.apply[A](
+      Scala2Naming.inferName[A],
+      Resources.inferRootDir(typeTagA.mirror.runtimeClass(typeTagA.tpe)),
+      Scala2Naming.inferPackage[A],
+      size,
+      count,
+      printer
+    )
+}

golden/src/main/scala-2/io/circe/testing/golden/Scala2Naming.scala

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2016 circe
+ *
+ * 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 io.circe.testing.golden
+
+import scala.reflect.runtime.universe.Symbol
+import scala.reflect.runtime.universe.Type
+import scala.reflect.runtime.universe.TypeTag
+
+object Scala2Naming {
+
+  /**
+   * Attempt to guess the packaging of the type indicated by the provided type tag.
+   */
+  def inferPackage[A](implicit A: TypeTag[A]): List[String] =
+    owners(A.tpe).collectFirst { case s if s.isPackage => s.fullName.split('.').toList }.getOrElse(List.empty)
+
+  private def owners(tpe: Type): Iterator[Symbol] =
+    Iterator.iterate(tpe.typeSymbol)(_.owner)
+
+  /**
+   * Attempt to guess the name of the type indicated by the provided type tag.
+   */
+  def inferName[A](implicit A: TypeTag[A]): String = inferNameForType(A.tpe)
+
+  private def baseSymbols(tpe: Type): List[Symbol] =
+    owners(tpe).takeWhile(!_.isPackage).toList.reverse
+
+  private def inferNameForType(tpe: Type): String = {
+    val baseNames = baseSymbols(tpe).map(_.name.decodedName.toString)
+
+    (baseNames ::: tpe.typeArgs.map(inferNameForType)).mkString("_")
+  }
+}

golden/src/main/scala-3/io/circe/testing/golden/GoldenCodecTestsCompanion.scala

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2016 circe
+ *
+ * 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 io.circe.testing.golden
+
+import io.circe.Decoder
+import io.circe.Encoder
+import io.circe.Printer
+import org.scalacheck.Arbitrary
+
+import scala.reflect.ClassTag
+
+trait GoldenCodecTestsCompanion { self: GoldenCodecTests.type =>
+  inline def apply[A: Decoder: Encoder: Arbitrary: ClassTag]: GoldenCodecTests[A] =
+    fromLaws[A](ResourceFileGoldenCodecLaws[A]())
+
+  inline def apply[A: Decoder: Encoder: Arbitrary: ClassTag](printer: Printer): GoldenCodecTests[A] =
+    fromLaws[A](ResourceFileGoldenCodecLaws[A](printer = printer))
+
+  inline def apply[A: Decoder: Encoder: Arbitrary: ClassTag](count: Int): GoldenCodecTests[A] =
+    fromLaws[A](ResourceFileGoldenCodecLaws[A](count = count))
+
+  inline def apply[A: Decoder: Encoder: Arbitrary: ClassTag](count: Int, printer: Printer): GoldenCodecTests[A] =
+    fromLaws[A](ResourceFileGoldenCodecLaws[A](count = count, printer = printer))
+}

golden/src/main/scala-3/io/circe/testing/golden/ResourceFileGoldenCodecLawsCompanion.scala

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2016 circe
+ *
+ * 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 io.circe.testing.golden
+
+import io.circe.Decoder
+import io.circe.Encoder
+import io.circe.Printer
+import org.scalacheck.Arbitrary
+
+import scala.reflect.ClassTag
+
+trait ResourceFileGoldenCodecLawsCompanion { self: ResourceFileGoldenCodecLaws.type =>
+
+  inline def apply[A](
+    size: Int = 100,
+    count: Int = 1,
+    printer: Printer = Printer.spaces2
+  )(using
+    decodeA: Decoder[A],
+    encodeA: Encoder[A],
+    arbitraryA: Arbitrary[A],
+    classT: ClassTag[A]
+  ): GoldenCodecLaws[A] =
+    self.apply[A](
+      Scala3Naming.name[A],
+      Resources.inferRootDir(classT.runtimeClass),
+      Scala3Naming.pkg[A],
+      size,
+      count,
+      printer
+    )
+}