grpc-pb: Support maps

grpc/grpc-core/src/commonTest/kotlin/kotlinx/rpc/grpc/pb/ProtosTest.kt

@@ -14,11 +14,8 @@ import encodeWith
 import invoke
 import kotlinx.io.Buffer
 import kotlinx.rpc.grpc.codec.MessageCodec
-import kotlinx.rpc.grpc.test.MyEnum
-import kotlinx.rpc.grpc.test.UsingEnum
-import kotlinx.rpc.grpc.test.UsingEnumInternal
+import kotlinx.rpc.grpc.test.*
 import kotlinx.rpc.grpc.test.common.*
-import kotlinx.rpc.grpc.test.invoke
 import test.nested.*
 import test.recursive.Recursive
 import test.recursive.RecursiveInternal
@@ -31,7 +28,7 @@ class ProtosTest {
 
     private fun <M> encodeDecode(
         msg: M,
-        codec: MessageCodec<M>
+        codec: MessageCodec<M>,
     ): M {
         val source = codec.encode(msg)
         return codec.decode(source)
@@ -357,4 +354,38 @@ class ProtosTest {
         assertEquals("fourth", decoded.other.arg3)
     }
 
+
+    @Test
+    fun testMap() {
+        val msg = TestMap {
+            primitives = mapOf("one" to 1, "two" to 2, "three" to 3)
+            messages = mapOf(
+                1 to PresenceCheck { RequiredPresence = 1 },
+                2 to PresenceCheck { RequiredPresence = 2; OptionalPresence = 3F }
+            )
+        }
+
+        val decoded = encodeDecode(msg, TestMapInternal.CODEC)
+        assertEquals(msg.primitives, decoded.primitives)
+        assertEquals(msg.messages.size, decoded.messages.size)
+        for ((key, value) in msg.messages) {
+            assertEquals(value.RequiredPresence, decoded.messages[key]!!.RequiredPresence)
+            assertEquals(value.OptionalPresence, decoded.messages[key]!!.OptionalPresence)
+        }
+    }
+
+    @Test
+    fun testMapRequiredSubField() {
+        // we use the internal constructor to avoid a "missing required field" error during object construction
+        val missingRequiredMessage = PresenceCheckInternal()
+
+        assertFailsWith<IllegalStateException> {
+            val msg = TestMap {
+                messages = mapOf(
+                    2 to missingRequiredMessage
+                )
+            }
+        }
+    }
+
 }

grpc/grpc-core/src/commonTest/proto/exclude/test_map.proto → grpc/grpc-core/src/commonTest/proto/test_map.proto

@@ -2,9 +2,9 @@ syntax = "proto3";
 
 package kotlinx.rpc.grpc.test;
 
-import "reference_package.proto";
+import "presence_check.proto";
 
 message TestMap {
   map<string, int64> primitives = 1;
-  map<string, References> references = 2;
-}
+  map<int32, kotlinx.rpc.grpc.test.common.PresenceCheck> messages = 2;
+}

protoc-gen/src/main/kotlin/kotlinx/rpc/protobuf/CodeGenerator.kt

@@ -72,10 +72,11 @@ open class CodeGenerator(
         suffix: String = "",
         nlAfterClosed: Boolean = true,
         openingBracket: Boolean = true,
+        paramDecl: String = "",
         block: (CodeGenerator.() -> Unit)? = null,
     ) {
         addLine(prefix)
-        scopeWithSuffix(suffix, openingBracket, nlAfterClosed, block)
+        scopeWithSuffix(suffix, openingBracket, nlAfterClosed, paramDecl, block)
     }
 
     internal fun ifBranch(
@@ -122,6 +123,7 @@ open class CodeGenerator(
         suffix: String = "",
         openingBracket: Boolean = true,
         nlAfterClosed: Boolean = true,
+        paramDeclaration: String = "",
         block: (CodeGenerator.() -> Unit)? = null,
     ) {
         if (block == null) {
@@ -139,7 +141,7 @@ open class CodeGenerator(
         }
 
         if (openingBracket) {
-            append(" {")
+            append(" { $paramDeclaration")
         }
         newLine()
         append(nested.build().trimEnd())