From 3867258fe623737c4d0b0a454aaedf72fbe8e2a7 Mon Sep 17 00:00:00 2001
From: Mark Spanbroek <mark@spanbroek.net>
Date: Tue, 23 Feb 2021 12:30:55 +0100
Subject: [PATCH] Fix ABI encoding of outcome; should be in a tuple

---
 nitro/outcome.nim           | 7 ++++++-
 tests/nitro/examples.nim    | 3 +++
 tests/nitro/testOutcome.nim | 8 ++++++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/nitro/outcome.nim b/nitro/outcome.nim
index c55227d..8be7d54 100644
--- a/nitro/outcome.nim
+++ b/nitro/outcome.nim
@@ -6,7 +6,7 @@ export types
 export abi
 
 type
-  Outcome* = seq[AssetOutcome]
+  Outcome* = distinct seq[AssetOutcome]
   AssetOutcomeType* = enum
     allocationType = 0
     guaranteeType = 1
@@ -56,5 +56,10 @@ proc write*(writer: var AbiWriter, assetOutcome: AssetOutcome) =
   writer.write(content.finish())
   writer.finishTuple()
 
+proc write*(writer: var AbiWriter, outcome: Outcome) =
+  writer.startTuple()
+  writer.write(seq[AssetOutcome](outcome))
+  writer.finishTuple()
+
 proc hashOutcome*(outcome: Outcome): array[32, byte] =
   keccak256.digest(Abi.encode(outcome)).data
diff --git a/tests/nitro/examples.nim b/tests/nitro/examples.nim
index 3becd48..1e436e1 100644
--- a/tests/nitro/examples.nim
+++ b/tests/nitro/examples.nim
@@ -62,6 +62,9 @@ proc example*(_: type AssetOutcome): AssetOutcome =
       guarantee: Guarantee.example
     )
 
+proc example*(_: type Outcome): Outcome =
+  Outcome(seq[AssetOutcome].example)
+
 proc example*(_: type State): State =
   State(
     turnNum: UInt48.example,
diff --git a/tests/nitro/testOutcome.nim b/tests/nitro/testOutcome.nim
index aa02931..fed7a51 100644
--- a/tests/nitro/testOutcome.nim
+++ b/tests/nitro/testOutcome.nim
@@ -59,6 +59,14 @@ suite "outcome":
     writer.finishTuple()
     check Abi.encode(assetOutcome) == writer.finish()
 
+  test "encodes outcomes":
+    let outcome = Outcome.example()
+    var writer: AbiWriter
+    writer.startTuple()
+    writer.write(seq[AssetOutcome](outcome))
+    writer.finishTuple()
+    check Abi.encode(outcome) == writer.finish()
+
   test "hashes outcomes":
     let outcome = Outcome.example
     let encoded = Abi.encode(outcome)