~review fixes

Author: shanshin

formats/protobuf/commonMain/src/kotlinx/serialization/protobuf/internal/Helpers.kt

@@ -87,7 +87,7 @@ internal fun SerialDescriptor.extractParameters(index: Int): ProtoDesc {
         val annotation = annotations[i]
         if (annotation is ProtoNumber) {
             protoId = annotation.number
-            checkFieldNumber(protoId, this)
+            checkFieldNumber(protoId, i, this)
         } else if (annotation is ProtoType) {
             format = annotation.type
         } else if (annotation is ProtoPacked) {
@@ -121,16 +121,16 @@ internal fun extractProtoId(descriptor: SerialDescriptor, index: Int, zeroBasedD
             result = annotation.number
             // 0 or negative numbers are acceptable for enums
             if (!zeroBasedDefault) {
-                checkFieldNumber(result, descriptor)
+                checkFieldNumber(result, i, descriptor)
             }
         }
     }
     return result
 }
 
-private fun checkFieldNumber(fieldNumber: Int, descriptor: SerialDescriptor) {
+private fun checkFieldNumber(fieldNumber: Int, propertyIndex: Int, descriptor: SerialDescriptor) {
     if (fieldNumber <= 0) {
-        throw SerializationException("$fieldNumber is not allowed in ProtoNumber for ${descriptor.serialName}, because protobuf support field numbers in range 1..${Int.MAX_VALUE}}")
+        throw SerializationException("$fieldNumber is not allowed in ProtoNumber for property '${descriptor.getElementName(propertyIndex)}' of '${descriptor.serialName}', because protobuf support field numbers in range 1..${Int.MAX_VALUE}")
     }
 }
 

formats/protobuf/commonMain/src/kotlinx/serialization/protobuf/internal/ProtobufDecoding.kt

@@ -46,8 +46,8 @@ internal open class ProtobufDecoder(
              * array for the fast-path. Fast-path implies that elements are not marked with @ProtoId
              * explicitly or are monotonic and incremental (maybe, 1-indexed)
              *
-             * Since the library allows the use of fields with proto ID 0,
-             * it is necessary to initialize all elements, because there will always be one extra element
+             * Initialize all elements, because there will always be one extra element as arrays are numbered from 0
+             * but in protobuf field number starts from 1.
              * in the fast path array, which is missing from the descriptor
              */
             val cache = IntArray(elements + 1) { -1 }

formats/protobuf/commonTest/src/kotlinx/serialization/protobuf/AutoAssignIdsTest.kt

@@ -30,4 +30,15 @@ class AutoAssignIdsTest {
         assertEquals(w1.a, w2.a)
         assertEquals(w1.b, w2.b)
     }
+
+    class NestedClass {
+        companion object
+    }
+
+    object X
+
+    @Test
+    fun testName() {
+        println(X::class.qualifiedName)
+    }
 }

formats/protobuf/commonTest/src/kotlinx/serialization/protobuf/InvalidFieldNumberTest.kt

@@ -42,29 +42,29 @@ class InvalidFieldNumberTest {
 
     @Test
     fun testSerializeZeroProtoNumber() {
-        assertFailsWithMessage<SerializationException>("0 is not allowed in ProtoNumber for kotlinx.serialization.protobuf.InvalidFieldNumberTest.ZeroProtoNumber, because protobuf support field values in range 1..2147483647") {
+        assertFailsWithMessage<SerializationException>("0 is not allowed in ProtoNumber for property 'value' of 'kotlinx.serialization.protobuf.InvalidFieldNumberTest.ZeroProtoNumber', because protobuf support field numbers in range 1..2147483647") {
             ProtoBuf.encodeToHexString(ZeroProtoNumber(42))
         }
     }
 
     @Test
     fun testDeserializeZeroProtoNumber() {
-        assertFailsWithMessage<SerializationException>("0 is not allowed in ProtoNumber for kotlinx.serialization.protobuf.InvalidFieldNumberTest.ZeroProtoNumber, because protobuf support field values in range 1..2147483647") {
+        assertFailsWithMessage<SerializationException>("0 is not allowed in ProtoNumber for property 'value' of 'kotlinx.serialization.protobuf.InvalidFieldNumberTest.ZeroProtoNumber', because protobuf support field numbers in range 1..2147483647") {
             ProtoBuf.decodeFromHexString<ZeroProtoNumber>("000f")
         }
     }
 
     @Test
     fun testSerializeNegativeProtoNumber() {
-        assertFailsWithMessage<SerializationException>("-5 is not allowed in ProtoNumber for kotlinx.serialization.protobuf.InvalidFieldNumberTest.NegativeProtoNumber, because protobuf support field values in range 1..2147483647") {
+        assertFailsWithMessage<SerializationException>("-5 is not allowed in ProtoNumber for property 'value' of 'kotlinx.serialization.protobuf.InvalidFieldNumberTest.NegativeProtoNumber', because protobuf support field numbers in range 1..2147483647") {
             ProtoBuf.encodeToHexString(NegativeProtoNumber(42))
         }
     }
 
     @Test
     fun testDeserializeNegativeProtoNumber() {
-        assertFailsWithMessage<SerializationException>("-5 is not allowed in ProtoNumber for kotlinx.serialization.protobuf.InvalidFieldNumberTest.NegativeProtoNumber, because protobuf support field values in range 1..2147483647") {
+        assertFailsWithMessage<SerializationException>("-5 is not allowed in ProtoNumber for property 'value' of 'kotlinx.serialization.protobuf.InvalidFieldNumberTest.NegativeProtoNumber', because protobuf support field numbers in range 1..2147483647") {
             ProtoBuf.decodeFromHexString<NegativeProtoNumber>("000f")
         }
     }
-}
+}