From ca4e938a7509bbec7f7352cf2f22d78be408ab86 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Tue, 26 Sep 2017 20:22:54 -0700
Subject: [PATCH] mempool: fix orphan resolution edge case.

---
 lib/mempool/mempool.js | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/lib/mempool/mempool.js b/lib/mempool/mempool.js
index aae2755a..04cb55cd 100644
--- a/lib/mempool/mempool.js
+++ b/lib/mempool/mempool.js
@@ -1562,7 +1562,16 @@ Mempool.prototype.handleOrphans = async function handleOrphans(parent) {
       throw err;
     }
 
-    assert(!missing || missing.length === 0);
+    // Can happen if an existing parent is
+    // evicted in the interim between fetching
+    // the non-present parents.
+    if (missing && missing.length > 0) {
+      this.logger.debug(
+        'Transaction %s was double-orphaned in mempool.',
+        tx.txid());
+      this.removeOrphan(tx.hash('hex'));
+      continue;
+    }
 
     this.logger.debug('Resolved orphan %s in mempool.', tx.txid());
   }