From 3b30fdb99af14a43eb0e9762861f5fabc2481cca Mon Sep 17 00:00:00 2001
From: SW van Heerden <swvheerden@gmail.com>
Date: Tue, 2 Aug 2022 12:19:26 +0200
Subject: [PATCH] fix: burned output check (#4374)

Description
---
fixes the burned output check.
Adds in a unit test to ensure its correct

How Has This Been Tested?
---
Unit and integration
---
 base_layer/core/src/validation/helpers.rs | 56 ++++++++++++++++++++++-
 1 file changed, 55 insertions(+), 1 deletion(-)

diff --git a/base_layer/core/src/validation/helpers.rs b/base_layer/core/src/validation/helpers.rs
index ac9c2dada6..b1eca6ea4d 100644
--- a/base_layer/core/src/validation/helpers.rs
+++ b/base_layer/core/src/validation/helpers.rs
@@ -280,7 +280,7 @@ pub fn check_total_burned(body: &AggregateBody) -> Result<(), ValidationError> {
         }
     }
     for kernel in body.kernels() {
-        if kernel.is_burned() && burned_outputs.remove(kernel.get_burn_commitment()?) {
+        if kernel.is_burned() && !burned_outputs.remove(kernel.get_burn_commitment()?) {
             return Err(ValidationError::InvalidBurnError(
                 "Burned kernel does not match burned output".to_string(),
             ));
@@ -1039,4 +1039,58 @@ mod test {
             unpack_enum!(TransactionError::InvalidCoinbase = err);
         }
     }
+
+    use crate::{covenants::Covenant, transactions::transaction_components::KernelFeatures};
+
+    #[test]
+    fn check_burned_succeeds_for_valid_outputs() {
+        let mut kernel1 = test_helpers::create_test_kernel(0.into(), 0);
+        let mut kernel2 = test_helpers::create_test_kernel(0.into(), 0);
+
+        let (output1, _, _) = test_helpers::create_utxo(
+            100.into(),
+            &CryptoFactories::default(),
+            &OutputFeatures::create_burn_output(),
+            &TariScript::default(),
+            &Covenant::default(),
+            0.into(),
+        );
+        let (output2, _, _) = test_helpers::create_utxo(
+            101.into(),
+            &CryptoFactories::default(),
+            &OutputFeatures::create_burn_output(),
+            &TariScript::default(),
+            &Covenant::default(),
+            0.into(),
+        );
+        let (output3, _, _) = test_helpers::create_utxo(
+            102.into(),
+            &CryptoFactories::default(),
+            &OutputFeatures::create_burn_output(),
+            &TariScript::default(),
+            &Covenant::default(),
+            0.into(),
+        );
+
+        kernel1.features = KernelFeatures::create_burn();
+        kernel1.burn_commitment = Some(output1.commitment.clone());
+        kernel2.features = KernelFeatures::create_burn();
+        kernel2.burn_commitment = Some(output2.commitment.clone());
+        let kernel3 = kernel1.clone();
+
+        let mut body = AggregateBody::new(Vec::new(), vec![output1.clone(), output2.clone()], vec![
+            kernel1.clone(),
+            kernel2.clone(),
+        ]);
+        assert!(check_total_burned(&body).is_ok());
+        // lets add an extra kernel
+        body.add_kernels(&mut vec![kernel3]);
+        assert!(check_total_burned(&body).is_err());
+        // lets add a kernel commitment mismatch
+        body.add_outputs(&mut vec![output3.clone()]);
+        assert!(check_total_burned(&body).is_err());
+        // Lets try one with a commitment with no kernel
+        let body2 = AggregateBody::new(Vec::new(), vec![output1, output2, output3], vec![kernel1, kernel2]);
+        assert!(check_total_burned(&body2).is_err());
+    }
 }