Implement Reader#getUIntExact().

shared/src/main/scala/scorex/util/Extensions.scala

@@ -74,6 +74,7 @@ object Extensions {
       * If `Long` value is out of the possible range for a [[scala.Int]] result,
       * then a `java.lang.ArithmeticException` is thrown.
       */
+    @deprecated("Use Reader#getUIntExact() instead")
     def toIntExact: Int = {
       if (x < Int.MinValue || x > Int.MaxValue)
         throw new ArithmeticException("Int overflow")
@@ -86,7 +87,7 @@ object Extensions {
 
     /**
       * Safely casting each element of collection to be type of `B`.
-      * If element can not to be cast to `B` then `AssertionError` is thrown
+      * If element can not to be cast to `B` then `IllegalArgumentException` is thrown
       */
     def cast[B:ClassTag]: Source[B] = {
 

shared/src/main/scala/scorex/util/serialization/Reader.scala

@@ -68,8 +68,15 @@ abstract class Reader {
     * Decode positive Int.
     * @return signed Long
     */
+  @deprecated("Use getUIntExact() instead")
   def getUInt(): Long
 
+  /**
+    * Decode positive Int.
+    * @return unsigned 31-bit Int
+    */
+  def getUIntExact(): Int
+
   /**
     * Decode signed Long.
     * @return signed Long

shared/src/main/scala/scorex/util/serialization/VLQReader.scala

@@ -25,7 +25,7 @@ trait VLQReader extends Reader {
     * Decode Short previously encoded with [[VLQWriter.putUShort]] using VLQ.
     * @see [[https://en.wikipedia.org/wiki/Variable-length_quantity]]
     * @return Int
-    * @throws AssertionError for deserialized values not in unsigned Short range
+    * @throws IllegalArgumentException for deserialized values not in unsigned Short range
     */
   @inline override def getUShort(): Int = {
     val x = getULong().toInt
@@ -50,13 +50,26 @@ trait VLQReader extends Reader {
     * Decode Int previously encoded with [[VLQWriter.putUInt]] using VLQ.
     * @see [[https://en.wikipedia.org/wiki/Variable-length_quantity]]
     * @return Long
+    * @throws IllegalArgumentException for deserialized values not in unsigned Int range
     */
   @inline override def getUInt(): Long = {
     val x = getULong()
     require(x >= 0L && x <= 0xFFFFFFFFL, s"$x is out of unsigned int range")
     x
   }
 
+  /**
+    * Decode Int previously encoded with [[VLQWriter.putUInt]] using VLQ.
+    * @see [[https://en.wikipedia.org/wiki/Variable-length_quantity]]
+    * @return Int
+    * @throws IllegalArgumentException for deserialized values not in unsigned 31-bit Int range
+    */
+  @inline override def getUIntExact(): Int = {
+    val x = getULong()
+    require(x >= 0L && x <= Int.MaxValue.toLong, s"$x is out of unsigned 31-bit int range")
+    x.toInt
+  }
+
   /**
     * Decode signed Long previously encoded with [[VLQWriter.putLong]] using VLQ with ZigZag.
     *

shared/src/main/scala/scorex/util/serialization/VLQWriter.scala

@@ -31,7 +31,7 @@ trait VLQWriter extends Writer {
     *
     * @see [[https://en.wikipedia.org/wiki/Variable-length_quantity]]
     * @param x unsigned Short in a range 0 <= x <= 0xFFFF represented as Int
-    * @throws AssertionError for values not in unsigned Short range
+    * @throws IllegalArgumentException for values not in unsigned Short range
     */
   @inline override def putUShort(x: Int): this.type = {
     require(x >= 0 && x <= 0xFFFF, s"Value $x is out of unsigned short range")
@@ -59,7 +59,7 @@ trait VLQWriter extends Writer {
     *
     * @see [[https://en.wikipedia.org/wiki/Variable-length_quantity]]
     * @param x unsigned Int
-    * @throws AssertionError for values not in unsigned Int range
+    * @throws IllegalArgumentException for values not in unsigned Int range
     */
   @inline override def putUInt(x: Long): this.type = {
     require(x >= 0 && x <= 0xFFFFFFFFL, s"$x is out of unsigned int range")
@@ -151,7 +151,7 @@ trait VLQWriter extends Writer {
     * Encode String is shorter than 256 bytes
     *
     * @param s String
-    * @return
+    * @throws IllegalArgumentException for strings longer than 255 bytes
     */
   override def putShortString(s: String): this.type = {
     val bytes = s.getBytes

shared/src/main/scala/scorex/util/serialization/Writer.scala

@@ -46,7 +46,7 @@ abstract class Writer {
     * Encode integer as an unsigned byte asserting the range check
     * @param x integer value to encode
     * @return
-    * @throws AssertionError if x is outside of the unsigned byte range
+    * @throws IllegalArgumentException if x is outside of the unsigned byte range
     */
   def putUByte(x: Int): this.type = {
     require(x >= 0 && x <= 0xFF, s"$x is out of unsigned byte range")

shared/src/test/scala/scorex/util/serialization/VLQReaderWriterSpecification.scala

@@ -338,6 +338,18 @@ trait VLQReaderWriterSpecification extends AnyPropSpec
     }
   }
 
+  property("unsigned Int roundtrip exact"){
+    forAll(Gen.chooseNum(0, Int.MaxValue)) { x: Int =>
+      byteBufReader(byteArrayWriter().putUInt(x.toLong).toBytes).getUIntExact() shouldBe x
+    }
+    forAll(Gen.chooseNum(Long.MinValue, -1L)) { x: Long =>
+      an[IllegalArgumentException] should be thrownBy byteBufReader(byteArrayWriter().putULong(x).toBytes).getUIntExact()
+    }
+    forAll(Gen.chooseNum(Int.MaxValue.toLong + 1L, Long.MaxValue)) { x: Long =>
+      an[IllegalArgumentException] should be thrownBy byteBufReader(byteArrayWriter().putULong(x).toBytes).getUIntExact()
+    }
+  }
+
   property("Long roundtrip") {
     forAll { (v: Long) => byteBufReader(byteArrayWriter().putLong(v).toBytes).getLong() shouldBe v }
   }