Candidate for 6.0.0 release

.gitignore

@@ -8,6 +8,7 @@
 *.fdb_latexmk
 *.gz
 
+yarn.lock
 *.log
 docs/spec/out/
 test-out/

core/js/src/main/scala/sigma/crypto/Platform.scala

@@ -253,6 +253,7 @@ object Platform {
     case _: Boolean => tpe == SBoolean
     case _: Byte | _: Short | _: Int | _: Long => tpe.isInstanceOf[SNumericType]
     case _: BigInt => tpe == SBigInt
+    case _: UnsignedBigInt => tpe == SUnsignedBigInt
     case _: String => tpe == SString
     case _: GroupElement => tpe.isGroupElement
     case _: SigmaProp => tpe.isSigmaProp

core/js/src/main/scala/sigma/js/Isos.scala

@@ -1,7 +1,7 @@
 package sigma.js
 
 import sigma.{Coll, Colls}
-import sigma.data.{CBigInt, Iso, RType}
+import sigma.data.{CBigInt, CUnsignedBigInt, Iso, RType}
 
 import java.math.BigInteger
 import scala.reflect.ClassTag
@@ -42,6 +42,18 @@ object Isos {
     }
   }
 
+  implicit val isoUnsignedBigInt: Iso[js.BigInt, sigma.UnsignedBigInt] = new Iso[js.BigInt, sigma.UnsignedBigInt] {
+    override def to(x: js.BigInt): sigma.UnsignedBigInt = {
+      CUnsignedBigInt(new BigInteger(x.toString(10)))
+    }
+
+    override def from(x: sigma.UnsignedBigInt): js.BigInt = {
+      val bi = x.asInstanceOf[CUnsignedBigInt].wrappedValue
+      val s  = bi.toString(10)
+      js.BigInt(s)
+    }
+  }
+
   implicit val isoBigIntToLong: Iso[js.BigInt, Long] = new Iso[js.BigInt, Long] {
     override def to(x: js.BigInt): Long = java.lang.Long.parseLong(x.toString(10))
 

core/js/src/main/scala/sigma/js/Type.scala

@@ -35,6 +35,9 @@ object Type extends js.Object {
   /** Descriptor of ErgoScript type BigInt. */
   val BigInt = new Type(sigma.BigIntRType)
 
+  /** Descriptor of ErgoScript type UnsignedBigInt. */
+  val UnsignedBigInt = new Type(sigma.UnsignedBigIntRType)
+
   /** Descriptor of ErgoScript type GroupElement. */
   val GroupElement = new Type(sigma.GroupElementRType)
 

core/jvm/src/main/scala/sigma/crypto/Platform.scala

@@ -185,6 +185,7 @@ object Platform {
     case _: Int => tpe == SInt
     case _: Long => tpe == SLong
     case _: BigInt => tpe == SBigInt
+    case _: UnsignedBigInt => tpe == SUnsignedBigInt
     case _: String => tpe == SString  // TODO v6.0: remove this case (see https://github.com/ScorexFoundation/sigmastate-interpreter/issues/905)
     case _: GroupElement => tpe.isGroupElement
     case _: SigmaProp => tpe.isSigmaProp

core/shared/src/main/scala/sigma/Colls.scala

@@ -45,6 +45,19 @@ trait Coll[@specialized A] {
     */
   def apply(i: Int): A
 
+  /** The element at given index or None if there is no such element. Indices start at `0`.
+    *
+    *  @param  i       the index
+    *  @return         the element at the given index, or None if there is no such element
+    */
+  def get(i: Int): Option[A] = {
+    if (isDefinedAt(i)) {
+      Some(apply(i))
+    } else {
+      None
+    }
+  }
+
   /** Tests whether this $coll contains given index.
     *
     *  The implementations of methods `apply` and `isDefinedAt` turn a `Coll[A]` into
@@ -76,6 +89,18 @@ trait Coll[@specialized A] {
     * produces a collection ((x0, y0), ..., (xK, yK)) where K = min(N, M) */
   def zip[@specialized B](ys: Coll[B]): Coll[(A, B)]
 
+  /**
+    * @return true if first elements of this collection form given `ys` collection, false otherwise.
+    *         E.g. [1,2,3] starts with [1,2]
+    */
+  def startsWith(ys: Coll[A]): Boolean
+
+  /**
+    * @return true if last elements of this collection form given `ys` collection, false otherwise.
+    *         E.g. [1,2,3] ends with [2,3]
+    */
+  def endsWith(ys: Coll[A]): Boolean
+
   /** Tests whether a predicate holds for at least one element of this collection.
     *  @param   p     the predicate used to test elements.
     *  @return        `true` if the given predicate `p` is satisfied by at least one element of this collection, otherwise `false`

core/shared/src/main/scala/sigma/Evaluation.scala

@@ -25,6 +25,7 @@ object Evaluation {
     case SAny => AnyType
     case SUnit => UnitType
     case SBigInt => BigIntRType
+    case SUnsignedBigInt => UnsignedBigIntRType
     case SBox => BoxRType
     case SContext => ContextRType
     case SGlobal => SigmaDslBuilderRType
@@ -67,6 +68,7 @@ object Evaluation {
     case AnyType => SAny
     case UnitType => SUnit
     case BigIntRType => SBigInt
+    case UnsignedBigIntRType => SUnsignedBigInt
     case GroupElementRType => SGroupElement
     case AvlTreeRType => SAvlTree
     case ot: OptionType[_] => SOption(rtypeToSType(ot.tA))