add removeBlock on Blockchain

fluency03 · May 1, 2018 · f4cdf68 · f4cdf68
1 parent fc4c0e1
commit f4cdf68
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Showing 3 changed files with 7 additions and 1 deletion.
diff --git a/src/main/scala/com/fluency03/blockchain/api/actors/BlockchainActor.scala b/src/main/scala/com/fluency03/blockchain/api/actors/BlockchainActor.scala
@@ -90,4 +90,6 @@ class BlockchainActor extends ActorSupport {
   }
 
 
+
+
 }
diff --git a/src/main/scala/com/fluency03/blockchain/core/Blockchain.scala b/src/main/scala/com/fluency03/blockchain/core/Blockchain.scala
@@ -11,7 +11,8 @@ import scala.annotation.tailrec
 /**
  * Blockchain with difficulty and the chain of Blocks.
  * @param difficulty Difficulty of a Blockchain
- * @param chain Chain of Blocks
+ * @param chain Chain of Blocks, the newest Block is on the head of the chain;
+ *              the first genesis Block is on the last of the chain
  */
 case class Blockchain(difficulty: Int = 4, chain: Seq[Block] = Seq(Block.genesisBlock)) {
 
@@ -20,6 +21,8 @@ case class Blockchain(difficulty: Int = 4, chain: Seq[Block] = Seq(Block.genesis
 
   def addBlock(newBlock: Block): Blockchain = Blockchain(difficulty, newBlock +: chain)
 
+  def removeBlock(): Blockchain = Blockchain(difficulty, chain.tail)
+
   def lastBlock(): Option[Block] = chain.headOption
 
   def mineNextBlock(newBlockData: String, transactions: Seq[Transaction]): Block = {

diff --git a/src/test/scala/com/fluency03/blockchain/core/BlockchainTest.scala b/src/test/scala/com/fluency03/blockchain/core/BlockchainTest.scala
@@ -65,6 +65,7 @@ class BlockchainTest extends FlatSpec with Matchers  {
     blockchainAdded.lastBlock().get shouldEqual expected
     blockchainAdded.isValid shouldEqual true
     blockchainAdded.length shouldEqual 2
+    blockchainAdded.removeBlock() shouldEqual blockchainToAdd
 
     val blockchainAdded2 = blockchainToAdd.addBlock("This is next Block!", Seq(t1, t2))
     val newLastBlock = blockchainAdded2.lastBlock().get
Original file line number	Diff line number	Diff line change
Expand Up		@@ -90,4 +90,6 @@ class BlockchainActor extends ActorSupport {
		}




		}