Panic when a transaction blocks after reading nothing

1 files changed, 3 insertions, 0 deletions

diff --git a/tx.go b/tx.go
index e90eb57..cdeac0b 100644
--- a/tx.go
+++ b/tx.go
@@ -36,6 +36,9 @@ func (tx *Tx) commit() {
 
 // wait blocks until another transaction modifies any of the Vars read by tx.
 func (tx *Tx) wait() {
+	if len(tx.reads) == 0 {
+		panic("not waiting on anything")
+	}
 	for v := range tx.reads {
 		v.watchers.Store(tx, nil)
 	}