ScalaPB Plugin: Add option scala3_sources

contrib/scalapblib/readme.adoc

@@ -47,6 +47,8 @@ example/
 
 * scalaPBSearchDeps - A `Boolean` option which determines whether to search for `.proto` files in dependencies and add them to `scalaPBIncludePath`. Defaults to `false`.
 
+* scalaPBScala3Sources - Generate the sources with scala 3 syntax (i. e. use `?` instead of `_` in types)
+
 * scalaPBIncludePath - Additional paths to include `.proto` files when compiling.
 
 If you'd like to configure the https://scalapb.github.io/docs/scalapbc#passing-generator-parameters[options] that are passed to the ScalaPB compiler directly, you can override the `scalaPBOptions` task, for example:

contrib/scalapblib/src/mill/contrib/scalapblib/ScalaPBModule.scala

@@ -34,6 +34,8 @@ trait ScalaPBModule extends ScalaModule {
   /** ScalaPB enables lenses by default, this option allows you to disable it. */
   def scalaPBLenses: T[Boolean] = Task { true }
 
+  def scalaPBScala3Sources: T[Boolean] = T { false }
+
   def scalaPBSearchDeps: Boolean = false
 
   /**
@@ -68,7 +70,8 @@ trait ScalaPBModule extends ScalaModule {
             else
               Seq("single_line_to_string")
           }
-        )
+        ) ++
+        (if (scalaPBScala3Sources()) Seq("scala3_sources") else Seq.empty)
     ).mkString(",")
   }
 

contrib/scalapblib/test/src/mill/contrib/scalapblib/TutorialTests.scala

@@ -55,6 +55,12 @@ object TutorialTests extends TestSuite {
     }
   }
 
+  object TutorialWithScala3Soures extends TutorialBase {
+    object core extends TutorialModule {
+      override def scalaPBScala3Sources = { true }
+    }
+  }
+
   val resourcePath: os.Path = os.Path(sys.env("MILL_TEST_RESOURCE_DIR"))
 
   def protobufOutPath(eval: UnitTester): os.Path =
@@ -177,6 +183,12 @@ object TutorialTests extends TestSuite {
       }
     }
 
+    test("calledWithScala3Sources") - UnitTester(TutorialWithScala3Soures, resourcePath).scoped {
+      eval =>
+        val result = eval.apply(Tutorial.core.compileScalaPB)
+        assert(result.isRight)
+    }
+
     test("compilationArgs") {
       test("calledWithAdditionalArgs") - UnitTester(
         TutorialWithAdditionalArgs,