Fix memory leak in autowiring::signal

src/autowiring/signal.h

@@ -118,6 +118,7 @@ namespace autowiring {
         delete prior;
         prior = cur;
       }
+      delete prior;
     }
 
     signal& operator=(signal&& rhs) {

src/autowiring/test/AutoSignalTest.cpp

@@ -724,3 +724,12 @@ TEST_F(AutoSignalTest, IsExecuting) {
   };
   ASSERT_FALSE(sig.is_executing()) << "Signal was incorrectly marked as executing even though nothing is happening";
 }
+
+TEST_F(AutoSignalTest, NoLeaks) {
+  auto v = std::make_shared<bool>(false);
+  {
+    autowiring::signal<void()> x;
+    x += [v] {};
+  }
+  ASSERT_TRUE(v.unique()) << "Signal did not destroy all attached lambdas on its destruction";
+}

src/autowiring/test/OnceTest.cpp

@@ -33,7 +33,7 @@ TEST(OnceTest, CallAfterSet) {
   ASSERT_EQ(1, val2) << "Lambda not executed on assignment as expected";
 }
 
-TEST(OnceTest, NoLeaks) {
+TEST(OnceTest, NoLeaks_Asserted) {
   autowiring::once_signal<void> o;
   auto v = std::make_shared<bool>(false);
   o += [v] {};
@@ -45,6 +45,15 @@ TEST(OnceTest, NoLeaks) {
   ASSERT_TRUE(v.unique()) << "Shared pointer leaked by once flag after post-set attachment";
 }
 
+TEST(OnceTest, NoLeaks_NotAsserted) {
+  auto v = std::make_shared<bool>(false);
+  {
+    autowiring::once_signal<void()> x;
+    x += [v] {};
+  }
+  ASSERT_TRUE(v.unique()) << "Signal did not destroy all attached lambdas on its destruction";
+}
+
 TEST(OnceTest, MultiLambdaPending) {
   autowiring::once_signal<void> o;
   std::atomic<int> x{ 0 };