Disable code generator for files with only package-scoped options

For scalapb/scalapb-validate#70
scalapb · Jan 30, 2021 · fc40883 · fc40883
1 parent d998b26
commit fc40883
Show file tree

Hide file tree

Showing 3 changed files with 39 additions and 1 deletion.
diff --git a/compiler-plugin/src/main/scala/scalapb/compiler/DescriptorImplicits.scala b/compiler-plugin/src/main/scala/scalapb/compiler/DescriptorImplicits.scala
@@ -976,6 +976,18 @@ class DescriptorImplicits private[compiler] (
       file.getMessageTypes.asScala.foreach(visitMessage)
       messages.result()
     }
+
+    // Disable generating code when protobuf has package-scoped options and is
+    // otherwise empty. This is meant to allow users to add proto files with only
+    // package-scoped options as *source* files in their protoc command line, without
+    // worrying of duplicate source code being generated.
+    def disableOutput: Boolean =
+      (scalaOptions.getScope == Scalapb.ScalaPbOptions.OptionsScope.PACKAGE) &&
+        file.getEnumTypes().isEmpty &&
+        file.getMessageTypes().isEmpty() &&
+        file.getServices().isEmpty &&
+        file.getExtensions().isEmpty() &&
+        scalaOptions.getPreambleList().isEmpty()
   }
 
   private def allCapsToCamelCase(name: String, upperInitial: Boolean): String = {

diff --git a/compiler-plugin/src/main/scala/scalapb/compiler/ProtobufGenerator.scala b/compiler-plugin/src/main/scala/scalapb/compiler/ProtobufGenerator.scala
@@ -1669,7 +1669,7 @@ object ProtobufGenerator {
           val validator = new ProtoValidation(implicits)
           validator.validateFiles(request.allProtos)
           import implicits.FileDescriptorPimp
-          val files = request.filesToGenerate.flatMap { file =>
+          val files = request.filesToGenerate.filterNot(_.disableOutput).flatMap { file =>
             if (file.scalaOptions.getSingleFile)
               generator.generateSingleScalaFileForFileDescriptor(file)
             else generator.generateMultipleScalaFilesForFileDescriptor(file)

diff --git a/compiler-plugin/src/test/scala/scalapb/compiler/DescriptorImplicitsSpec.scala b/compiler-plugin/src/test/scala/scalapb/compiler/DescriptorImplicitsSpec.scala
@@ -98,4 +98,30 @@ class DescriptorImplicitsSpec extends AnyFlatSpec with Matchers with ProtocInvoc
       .scalaType
       .fullName must be("outside.outside.C")
   }
+
+  "disableOutput" should "be set for package option files" in {
+    val files = generateFileSet(base)
+    val implicits = new DescriptorImplicits(
+      GeneratorParams(flatPackage = false),
+      files,
+      SecondaryOutputProvider.empty
+    )
+    import implicits._
+
+    files
+      .find(_.getFullName() == "disable_flat.proto")
+      .get
+      .disableOutput must be(true)
+
+    files
+      .find(_.getFullName() == "enable_flat.proto")
+      .get
+      .disableOutput must be(false) // has a message Foo
+
+    files
+      .find(_.getFullName() == "inside_disable_flat.proto")
+      .get
+      .disableOutput must be(false)
+
+  }
 }