support incineration

ethereum/contracts/core/Forum.sol

@@ -75,6 +75,15 @@ contract Forum is Reputation {
         uint depth
     ) internal returns (int outboundAmount) {
         outboundAmount = (amount * citation.weightPercent) / 100;
+        if (citation.targetPostIndex == type(uint256).max) {
+            // Incineration
+            require(
+                outboundAmount >= 0,
+                "Leaching from incinerator is forbidden"
+            );
+            _burn(address(this), uint(outboundAmount));
+            return outboundAmount;
+        }
         int balanceToOutbound = _edgeBalances[postIndex][
             citation.targetPostIndex
         ];

ethereum/test/Forum.js

@@ -215,5 +215,18 @@ describe('Forum', () => {
       expect(posts[2].reputation).to.equal(0);
       expect(posts[3].reputation).to.equal(0);
     });
+
+    it('should be able to incinerate reputation', async () => {
+      await dao.addPost(account1, 'content-id-1', [
+        {
+          weightPercent: 50,
+          targetPostIndex: ethers.MaxUint256,
+        },
+      ]);
+      await initiateValidationPool({ postIndex: 0 });
+      expect(await dao.totalSupply()).to.equal(100);
+      await dao.evaluateOutcome(0);
+      expect((await dao.posts(0)).reputation).to.equal(50);
+    });
   });
 });