builder wip

scalapb · Nov 14, 2020 · 30cf569 · 30cf569
1 parent 6897c58
commit 30cf569
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Showing 2 changed files with 39 additions and 0 deletions.
diff --git a/compiler-plugin/src/main/scala/scalapb/compiler/ProtobufGenerator.scala b/compiler-plugin/src/main/scala/scalapb/compiler/ProtobufGenerator.scala
@@ -708,6 +708,17 @@ class ProtobufGenerator(
     printer.addWithDelimiter(",")(constructorFields(message).map(_.fullString))
   }
 
+  def generateBuilder(message: Descriptor)(printer: FunctionalPrinter): FunctionalPrinter = {
+    val myFullScalaName = message.scalaType.fullNameWithMaybeRoot(message)
+    printer.add(
+      s"class Builder extends _root_.scalapb.MessageBuilder[$myFullScalaName] {",
+    )
+    .indented(
+
+    )
+    .add("}")
+  }
+
   def generateMerge(message: Descriptor)(printer: FunctionalPrinter): FunctionalPrinter = {
     val myFullScalaName = message.scalaType.fullNameWithMaybeRoot(message)
     val requiredFieldMap: Map[FieldDescriptor, Int] =
@@ -1339,6 +1350,7 @@ class ProtobufGenerator(
       .call(generateNestedMessagesCompanions(message))
       .call(generateEnumCompanionForField(message))
       .call(generateDefaultInstance(message))
+      .call(generateBuilder(message))
       .print(message.getEnumTypes.asScala)(printEnum)
       .print(message.getRealOneofs.asScala)(printOneof)
       .print(message.nestedTypes)(printMessage)

diff --git a/scalapb-runtime/src/main/scala/scalapb/GeneratedMessageCompanion.scala b/scalapb-runtime/src/main/scala/scalapb/GeneratedMessageCompanion.scala
@@ -9,6 +9,7 @@ import scalapb.lenses.{Lens, Updatable}
 import _root_.scalapb.descriptors.{PMessage, PValue}
 import scala.util.Try
 import scala.annotation.nowarn
+import scala.annotation.unused
 
 trait GeneratedEnum extends Any with Product with Serializable {
   type EnumType <: GeneratedEnum
@@ -137,6 +138,32 @@ trait GeneratedMessage extends Any with Serializable {
   def toProtoString: String
 }
 
+abstract class MessageBuilder[A] {
+  def addInt(tag: Int, @unused value: Int): Unit = MessageBuilder.unmatchedTag(tag)
+
+  def addLong(tag: Int, @unused value: Long): Unit = MessageBuilder.unmatchedTag(tag)
+
+  def addFloat(tag: Int, @unused value: Float): Unit = MessageBuilder.unmatchedTag(tag)
+
+  def addDouble(tag: Int, @unused value: Double): Unit = MessageBuilder.unmatchedTag(tag)
+
+  def addString(tag: Int, @unused value: String): Unit = MessageBuilder.unmatchedTag(tag)
+
+  def addBoolean(tag: Int, @unused value: Boolean): Unit = MessageBuilder.unmatchedTag(tag)
+
+  def addEnumValue(tag: Int, @unused value: Int): Unit = MessageBuilder.unmatchedTag(tag)
+
+  def addByteString(tag: Int, @unused value: ByteString): Unit = MessageBuilder.unmatchedTag(tag)
+
+  def addMessage[T <: GeneratedMessage](tag: Int, @unused value: T): Unit = MessageBuilder.unmatchedTag(tag)
+
+  def result(): A
+}
+
+object MessageBuilder {
+  def unmatchedTag(tag: Int): Nothing = throw new RuntimeException(s"Unmatched tag $tag.")
+}
+
 trait ExtendableMessage[A <: ExtendableMessage[A]] extends Updatable[A] {
   self: A =>
   def unknownFields: _root_.scalapb.UnknownFieldSet