Allow interpreting BSON Int32 as Long when reading

Author: sebaciv

commons-mongo/jvm/src/main/scala/com/avsystem/commons/mongo/BsonReaderInput.scala

@@ -16,7 +16,10 @@ class BsonReaderInput(br: BsonReader, override val legacyOptionEncoding: Boolean
   override def readString(): String = br.readString()
   override def readBoolean(): Boolean = br.readBoolean()
   override def readInt(): Int = br.readInt32()
-  override def readLong(): Long = br.readInt64()
+  override def readLong(): Long = {
+    if (bsonType == BsonType.INT32) br.readInt32().toLong // allow to treat INT32 as Long
+    else br.readInt64()
+  }
   override def readTimestamp(): Long = br.readDateTime()
   override def readDouble(): Double = br.readDouble()
   override def readBigInt(): BigInt = BigInt(br.readBinaryData().getData)

commons-mongo/jvm/src/main/scala/com/avsystem/commons/mongo/BsonValueInput.scala

@@ -22,7 +22,10 @@ class BsonValueInput(bsonValue: BsonValue, override val legacyOptionEncoding: Bo
   def readString(): String = handleFailures(bsonValue.asString().getValue)
   def readBoolean(): Boolean = handleFailures(bsonValue.asBoolean().getValue)
   def readInt(): Int = handleFailures(bsonValue.asInt32().getValue)
-  def readLong(): Long = handleFailures(bsonValue.asInt64().getValue)
+  def readLong(): Long = {
+    if (bsonType == BsonType.INT32) handleFailures(bsonValue.asInt32().getValue.toLong) // allow to treat INT32 as Long
+    else handleFailures(bsonValue.asInt64().getValue)
+  }
   override def readTimestamp(): Long = handleFailures(bsonValue.asDateTime().getValue)
   def readDouble(): Double = handleFailures(bsonValue.asDouble().getValue)
   def readBigInt(): BigInt = handleFailures(BigInt(bsonValue.asBinary().getData))

commons-mongo/jvm/src/test/scala/com/avsystem/commons/mongo/BsonInputOutputTest.scala

@@ -68,6 +68,12 @@ class BsonValueGenCodecRoundtripTest extends GenCodecRoundtripTest {
 
   def createInput(raw: BsonValue): Input =
     new BsonValueInput(raw, legacyOptionEncoding)
+
+  test("Int32 to Long decoding") {
+    val input = createInput(new BsonInt32(42))
+    val result = input.readSimple().readLong()
+    assert(result == 42L)
+  }
 }
 
 class BsonInputOutputTest extends AnyFunSuite with ScalaCheckPropertyChecks {
@@ -131,6 +137,14 @@ class BsonInputOutputTest extends AnyFunSuite with ScalaCheckPropertyChecks {
     forAll(SomethingComplex.gen)(valueEncoding(_, legacyOptionEncoding = true))
   }
 
+  test("Int32 to Long decoding") {
+    val doc = new BsonDocument("value", new BsonInt32(42))
+    val reader = new BsonDocumentReader(doc)
+    val input = new BsonReaderInput(reader, false)
+    val sth = SomethingLong.codec.read(input)
+    assert(sth == SomethingLong(42))
+  }
+
   test("All encoding schemes with problematic map keys") {
     forAll(SomethingComplex.gen) { sth =>
       val sthBefore = sth.copy(

commons-mongo/jvm/src/test/scala/com/avsystem/commons/mongo/SomethingPlain.scala

@@ -80,3 +80,8 @@ object SomethingComplex {
 
   implicit val codec: GenCodec[SomethingComplex] = GenCodec.materialize
 }
+
+case class SomethingLong(value: Long)
+object SomethingLong {
+  implicit val codec: GenCodec[SomethingLong] = GenCodec.materialize
+}