Accept ints as doubles in Bson inputs

Author: pulewicz

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

@@ -37,8 +37,14 @@ class BsonReaderInput(br: BsonReader, override val legacyOptionEncoding: Boolean
   override def readTimestamp(): Long =
     expect(BsonType.DATE_TIME, br.readDateTime())
 
-  override def readDouble(): Double =
-    expect(BsonType.DOUBLE, br.readDouble())
+  override def readDouble(): Double = handleFailures {
+    bsonType match {
+      case BsonType.DOUBLE => br.readDouble()
+      case BsonType.INT32 => br.readInt32().toDouble
+      case BsonType.INT64 => br.readInt64().toDouble
+      case _ => wrongType(BsonType.DOUBLE, BsonType.INT32, BsonType.INT64)
+    }
+  }
 
   override def readBinary(): Array[Byte] =
     expect(BsonType.BINARY, br.readBinaryData().getData)

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

@@ -33,8 +33,14 @@ class BsonValueInput(bsonValue: BsonValue, override val legacyOptionEncoding: Bo
   override def readTimestamp(): Long =
     expect(BsonType.DATE_TIME, bsonValue.asDateTime().getValue)
 
-  def readDouble(): Double =
-    expect(BsonType.DOUBLE, bsonValue.asDouble().getValue)
+  override def readDouble(): Double = handleFailures {
+    bsonType match {
+      case BsonType.DOUBLE => bsonValue.asDouble().getValue
+      case BsonType.INT32 => readInt().toDouble
+      case BsonType.INT64 => bsonValue.asInt64().getValue.toDouble
+      case _ => wrongType(BsonType.DOUBLE, BsonType.INT32, BsonType.INT64)
+    }
+  }
 
   def readBinary(): Array[Byte] =
     expect(BsonType.BINARY, bsonValue.asBinary().getData)

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

@@ -75,6 +75,18 @@ class BsonValueGenCodecRoundtripTest extends GenCodecRoundtripTest {
     val result = input.readSimple().readLong()
     assert(result == 42L)
   }
+
+  test("Int32 to Double decoding") {
+    val input = createInput(new BsonInt32(43))
+    val result = input.readSimple().readDouble()
+    assert(result == 43D)
+  }
+
+  test("Int64 to Double decoding") {
+    val input = createInput(new BsonInt64(44))
+    val result = input.readSimple().readDouble()
+    assert(result == 44D)
+  }
 }
 
 class BsonInputOutputTest extends AnyFunSuite with ScalaCheckPropertyChecks {