Contracts: Rename ComedyPaper to CommercialPaper and rewrite the comment at the top to flag its not-realistic status.

src/contracts/CommercialPaper.kt

@@ -5,10 +5,14 @@ import java.security.PublicKey
 import java.time.Instant
 
 /**
- * "Comedy paper" is basically like commercial paper, but modelled by a non-expert and without any attention paid
- * to the issuance aspect. It has a weird name to emphasise that it's not a prototype of real CP, as that's currently
- * waiting for Jo/Ayoub to deliver full CP use case models. This file may be renamed later if it grows up and
- * becomes real CP.
+ * This is an ultra-trivial implementation of commercial paper, which is essentially a simpler version of a corporate
+ * bond. It can be seen as a company-specific currency. A company issues CP with a particular face value, like $100
+ * but sells it for less, say $90. The paper can be redeemed for cash at a given date in the future. Thus this example
+ * would have a 10% interest rate with a single repayment. Commercial paper is often rolled out (redeemed and the
+ * money used to immediately rebuy).
+ *
+ * This contract is not intended to realistically model CP. It is here only to act as a next step up above cash in
+ * the prototyping phase. It is thus very incomplete.
  *
  * Open issues:
  *  - In this model, you cannot merge or split CP. Can you do this normally? We could model CP as a specialised form
@@ -17,13 +21,11 @@ import java.time.Instant
  *    issue: need to find a cleaner way to allow this. Does the single-execution-per-transaction model make sense?
  */
 
-// TODO: This is very incomplete! Do not attempt to find mistakes in it just yet.
-
-val CP_PROGRAM_ID = SecureHash.sha256("comedy-paper")
+val CP_PROGRAM_ID = SecureHash.sha256("replace-me-later-with-bytecode-hash")
 
 // TODO: Generalise the notion of an owned instrument into a superclass/supercontract. Consider composition vs inheritance.
-object ComedyPaper : Contract {
-    override val legalContractReference: String = "https://www.gotlines.com/jokes/1"
+object CommercialPaper : Contract {
+    override val legalContractReference: String = "https://en.wikipedia.org/wiki/Commercial_paper"
 
     data class State(
         val issuance: InstitutionReference,
@@ -45,10 +47,10 @@ object ComedyPaper : Contract {
         with(tx) {
             // There are two possible things that can be done with CP. The first is trading it. The second is redeeming it
             // for cash on or after the maturity date.
-            val command = args.requireSingleCommand<ComedyPaper.Commands>()
+            val command = args.requireSingleCommand<CommercialPaper.Commands>()
 
             // For now do not allow multiple pieces of CP to trade in a single transaction. Study this more!
-            val input = inStates.filterIsInstance<ComedyPaper.State>().single()
+            val input = inStates.filterIsInstance<CommercialPaper.State>().single()
 
             requireThat {
                 "the transaction is signed by the owner of the CP" by (command.signers.contains(input.owner))
@@ -56,7 +58,7 @@ object ComedyPaper : Contract {
 
             when (command.value) {
                 is Commands.Move -> requireThat {
-                    val output = outStates.filterIsInstance<ComedyPaper.State>().single()
+                    val output = outStates.filterIsInstance<CommercialPaper.State>().single()
                     "the output state is the same as the input state except for owner" by (input.withoutOwner() == output.withoutOwner())
                 }
 
@@ -65,7 +67,7 @@ object ComedyPaper : Contract {
                     // Do we need to check the signature of the issuer here too?
                     "the paper must have matured" by (input.maturityDate < time)
                     "the received amount equals the face value" by (received == input.faceValue)
-                    "the paper must be destroyed" by outStates.filterIsInstance<ComedyPaper.State>().none()
+                    "the paper must be destroyed" by outStates.filterIsInstance<CommercialPaper.State>().none()
                 }
             }
         }

src/core/TestUtils.kt

@@ -35,7 +35,7 @@ val TEST_TX_TIME = Instant.parse("2015-04-17T12:00:00.00Z")
 // a sandbox. For now we just instantiate right at the start of the program.
 val TEST_PROGRAM_MAP: Map<SecureHash, Contract> = mapOf(
         CASH_PROGRAM_ID to Cash,
-        CP_PROGRAM_ID to ComedyPaper,
+        CP_PROGRAM_ID to CommercialPaper,
         DUMMY_PROGRAM_ID to DummyContract
 )
 

src/core/serialization/Kryo.kt

@@ -7,7 +7,7 @@ import com.esotericsoftware.kryo.io.Input
 import com.esotericsoftware.kryo.io.Output
 import com.esotericsoftware.kryo.serializers.JavaSerializer
 import contracts.Cash
-import contracts.ComedyPaper
+import contracts.CommercialPaper
 import core.*
 import java.io.ByteArrayOutputStream
 import java.lang.reflect.InvocationTargetException
@@ -223,9 +223,9 @@ fun createKryo(): Kryo {
         registerDataClass<Cash.State>()
         register(Cash.Commands.Move.javaClass)
         registerDataClass<Cash.Commands.Exit>()
-        registerDataClass<ComedyPaper.State>()
-        register(ComedyPaper.Commands.Move.javaClass)
-        register(ComedyPaper.Commands.Redeem.javaClass)
+        registerDataClass<CommercialPaper.State>()
+        register(CommercialPaper.Commands.Move.javaClass)
+        register(CommercialPaper.Commands.Redeem.javaClass)
 
         // And for unit testing ...
         registerDataClass<DummyPublicKey>()

tests/contracts/CommercialPaperTests.kt

@@ -5,8 +5,8 @@ import org.junit.Test
 
 // TODO: Finish this off.
 
-class ComedyPaperTests {
-    val PAPER_1 = ComedyPaper.State(
+class CommercialPaperTests {
+    val PAPER_1 = CommercialPaper.State(
             issuance = InstitutionReference(MEGA_CORP, OpaqueBytes.of(123)),
             owner = DUMMY_PUBKEY_1,
             faceValue = 1000.DOLLARS,
@@ -30,15 +30,15 @@ class ComedyPaperTests {
             this.rejects()
 
             transaction {
-                arg(DUMMY_PUBKEY_2) { ComedyPaper.Commands.Move }
+                arg(DUMMY_PUBKEY_2) { CommercialPaper.Commands.Move }
                 this `fails requirement` "is signed by the owner"
             }
 
-            arg(DUMMY_PUBKEY_1) { ComedyPaper.Commands.Move }
+            arg(DUMMY_PUBKEY_1) { CommercialPaper.Commands.Move }
             arg(DUMMY_PUBKEY_1) { Cash.Commands.Move }
             this.accepts()
         }.chain("a") {
-            arg(DUMMY_PUBKEY_2, MINI_CORP_KEY) { ComedyPaper.Commands.Redeem }
+            arg(DUMMY_PUBKEY_2, MINI_CORP_KEY) { CommercialPaper.Commands.Redeem }
 
             // No cash output, can't redeem like that!
             this.rejects("no cash being redeemed")