add tests for Blockchain

src/main/resources/genesis-block.json

@@ -0,0 +1,18 @@
+{
+  "header": {
+    "index": 0,
+    "previousHash": "0000000000000000000000000000000000000000000000000000000000000000",
+    "data": "Welcome to Blockchain in Scala!",
+    "merkleHash": "7814a9c43e9015462e5ffec1a3a9a69be024c1aacfa3ec4c879b5cd544761e7e",
+    "timestamp": 1523472721,
+    "nonce": 13860,
+    "hash": "00003607219f7a455e216f19ac3a34e3b158cf7282f7fdc624c93d593c2fc61f"
+  },
+  "transactions": [
+    {
+      "sender": "0000000000000000000000000000000000000000000000000000000000000000",
+      "receiver": "0000000000000000000000000000000000000000000000000000000000000000",
+      "amount": 50.0
+    }
+  ]
+}

src/main/scala/com/fluency03/blockchain/core/Block.scala

@@ -60,14 +60,14 @@ object Block {
 
   lazy val genesisBlock: Block = genesis()
 
-  def genesis(): Block =
+  def genesis(difficulty: Int = 4): Block =
     mineNextBlock(
         0,
         ZERO64,
         "Welcome to Blockchain in Scala!",
         List(Transaction(ZERO64, ZERO64, 50)),
         Instant.parse("2018-04-11T18:52:01Z").getEpochSecond,
-        4)
+        difficulty)
 
   def mineNextBlock(
       nextIndex: Int,

src/main/scala/com/fluency03/blockchain/core/Blockchain.scala

@@ -2,20 +2,24 @@ package com.fluency03.blockchain.core
 
 import com.fluency03.blockchain.Util.getCurrentTimestamp
 
-import scala.collection.mutable
+import scala.collection.mutable.ListBuffer
 
 /**
  * Blockchain with difficulty and the chain of Blocks.
  * @param difficulty Difficulty of a Blockchain
  * @param chain Chain of Blocks
  */
 case class Blockchain(difficulty: Int = 4, chain: List[Block] = List(Block.genesisBlock)) {
-  val currentTransactions: mutable.Set[Transaction] = new mutable.HashSet[Transaction]()
+  val currentTransactions: ListBuffer[Transaction] = new ListBuffer[Transaction]()
 
   def addBlock(newBlockData: String): Blockchain = {
     Blockchain(difficulty, mineNextBlock(newBlockData).addTransactions(currentTransactions.toList) :: chain)
   }
 
+  def addBlock(newBlock: Block): Blockchain = {
+    Blockchain(difficulty, newBlock :: chain)
+  }
+
   def addTransaction(t: Transaction): Blockchain = {
     currentTransactions += t
     this
@@ -24,7 +28,7 @@ case class Blockchain(difficulty: Int = 4, chain: List[Block] = List(Block.genes
   def addTransaction(sender: String, receiver: String, amount: Double): Blockchain =
     addTransaction(Transaction(sender, receiver, amount))
 
-  def addTransaction(trans: Set[Transaction]): Blockchain = {
+  def addTransactions(trans: List[Transaction]): Blockchain = {
     currentTransactions ++= trans
     this
   }
@@ -48,7 +52,7 @@ case class Blockchain(difficulty: Int = 4, chain: List[Block] = List(Block.genes
 
 object Blockchain {
 
-  def apply(difficulty: Int): Blockchain = new Blockchain(difficulty)
+  def apply(difficulty: Int): Blockchain = new Blockchain(difficulty, List(Block.genesis(difficulty)))
 
 }
 

src/test/resources/genesis-block.json

@@ -0,0 +1,18 @@
+{
+  "header": {
+    "index": 0,
+    "previousHash": "0000000000000000000000000000000000000000000000000000000000000000",
+    "data": "Welcome to Blockchain in Scala!",
+    "merkleHash": "7814a9c43e9015462e5ffec1a3a9a69be024c1aacfa3ec4c879b5cd544761e7e",
+    "timestamp": 1523472721,
+    "nonce": 13860,
+    "hash": "00003607219f7a455e216f19ac3a34e3b158cf7282f7fdc624c93d593c2fc61f"
+  },
+  "transactions": [
+    {
+      "sender": "0000000000000000000000000000000000000000000000000000000000000000",
+      "receiver": "0000000000000000000000000000000000000000000000000000000000000000",
+      "amount": 50.0
+    }
+  ]
+}

src/test/scala/com/fluency03/blockchain/core/BlockTest.scala

@@ -16,7 +16,7 @@ class BlockTest extends FlatSpec with Matchers {
         "merkleHash":"7814a9c43e9015462e5ffec1a3a9a69be024c1aacfa3ec4c879b5cd544761e7e",
         "timestamp":1523472721,
         "nonce":13860,
-        "hash":"00003607219f7a455e216f19ac3a34e3b158cf7282f7fdc624c93d593c2fc61f",
+        "hash":"00003607219f7a455e216f19ac3a34e3b158cf7282f7fdc624c93d593c2fc61f"
       },
       "transactions":[
         {

src/test/scala/com/fluency03/blockchain/core/BlockchainTest.scala

@@ -2,15 +2,68 @@ package com.fluency03.blockchain.core
 
 import org.scalatest.{FlatSpec, Matchers}
 
+import scala.collection.mutable.ListBuffer
+
 class BlockchainTest extends FlatSpec with Matchers  {
 
+  val blockchain: Blockchain = Blockchain()
+  val genesis: Block = Block.genesisBlock
+
+  val blockchainOf5: Blockchain = Blockchain(5)
+  val genesisOf5: Block = Block.genesis(5)
+
+  val t1: Transaction = Transaction(ZERO64, ZERO64, 10)
+  val t2: Transaction = Transaction(ZERO64, ZERO64, 20)
+  val t3: Transaction = Transaction(ZERO64, ZERO64, 30)
+  val t4: Transaction = Transaction(ZERO64, ZERO64, 40)
+
+  "A new Blockchain" should "have all default values." in {
+    blockchain.difficulty shouldEqual 4
+    blockchain.chain shouldEqual List(genesis)
+    blockchain.lastBlock().isEmpty shouldEqual false
+    blockchain.lastBlock().get shouldEqual genesis
+    blockchain.currentTransactions shouldEqual new ListBuffer[Transaction]()
+  }
 
+  "A new Blockchain with different difficulty" should "have all default values but the difficulty." in {
+    blockchainOf5.difficulty shouldEqual 5
+    blockchainOf5.chain shouldEqual List(genesisOf5)
+    blockchainOf5.lastBlock().isEmpty shouldEqual false
+    blockchainOf5.lastBlock().get shouldEqual genesisOf5
+    blockchainOf5.currentTransactions shouldEqual new ListBuffer[Transaction]()
+  }
 
+  "Add a Transaction to a Blockchain" should "add these Transactions to its currentTransactions collection." in {
+    val trans = new ListBuffer[Transaction]()
+    blockchain.addTransaction(t1)
+    trans += t1
+    blockchain.currentTransactions shouldEqual trans
 
+    blockchain.addTransaction(ZERO64, ZERO64, 20)
+    blockchain.addTransaction(t3)
+    trans ++= t2 :: t3 :: Nil
+    blockchain.currentTransactions shouldEqual trans
+  }
 
+  "Add a List of Transaction to a Blockchain" should "add these Transactions to its currentTransactions collection." in {
+    val trans = new ListBuffer[Transaction]()
+    blockchainOf5.addTransactions(t2 :: t3 :: t4 :: Nil)
+    trans ++= t2 :: t3 :: t4 :: Nil
+    blockchainOf5.currentTransactions shouldEqual trans
+  }
 
+  "Blockchain" should "be able to mine the next Block." in {
+    val blockchainToAdd: Blockchain = Blockchain()
+    val genesis: Block = Block.genesisBlock
 
+    val actual = blockchainToAdd.mineNextBlock("This is next Block!")
+    val expected = Block.mineNextBlock(genesis, "This is next Block!", List(), actual.timestamp, blockchain.difficulty)
+    actual shouldEqual expected
 
+    blockchainToAdd.lastBlock().get shouldEqual genesis
+    val blockchainAdded = blockchainToAdd.addBlock(actual)
+    blockchainAdded.lastBlock().get shouldEqual expected
+  }
 
 
 }