diff --git a/.gitignore b/.gitignore
index 992ce82..1e6b343 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,3 @@
 .vscode/
-docs/
-build/
+/docs/
+/build/
diff --git a/src/tinytest.cpp b/src/tinytest.cpp
index daad35d..b55c30f 100644
--- a/src/tinytest.cpp
+++ b/src/tinytest.cpp
@@ -161,12 +161,21 @@ TestResults TestResults::operator+(const TestResults& other) const {
 }
 
 TestResults& TestResults::operator+=(const TestResults& other) {
-  error_messages_.insert(error_messages_.end(), other.error_messages_.begin(), other.error_messages_.end());
+  if (this != &other) {
+    error_messages_.insert(error_messages_.end(), other.error_messages_.begin(), other.error_messages_.end());
+    failure_messages_.insert(failure_messages_.end(), other.failure_messages_.begin(), other.failure_messages_.end());
+    skip_messages_.insert(skip_messages_.end(), other.skip_messages_.begin(), other.skip_messages_.end());
+  } else {
+    const auto other_error_messages = other.error_messages_;
+    error_messages_.insert(error_messages_.end(), other_error_messages.begin(), other_error_messages.end());
+    const auto other_failure_messages = other.failure_messages_;
+    failure_messages_.insert(failure_messages_.end(), other_failure_messages.begin(), other_failure_messages.end());
+    const auto other_skip_messages = other.skip_messages_;
+    skip_messages_.insert(skip_messages_.end(), other_skip_messages.begin(), other_skip_messages.end());
+  }
   errors_ += other.errors_;
   failed_ += other.failed_;
-  failure_messages_.insert(failure_messages_.end(), other.failure_messages_.begin(), other.failure_messages_.end());
   passed_ += other.passed_;
-  skip_messages_.insert(skip_messages_.end(), other.skip_messages_.begin(), other.skip_messages_.end());
   skipped_ += other.skipped_;
   total_ += other.total_;
   return *this;
@@ -211,9 +220,11 @@ MaybeTestConfigureFunction Coalesce(MaybeTestConfigureFunction first, MaybeTestC
   if (first.has_value()) {
     if (second.has_value()) {
       // This is the only place we actually need to combine them.
-      return [&first, &second]() {
-        first.value()();
-        second.value()();
+      const auto& first_value = first.value();
+      const auto& second_value = second.value();
+      return [&first_value, &second_value]() {
+        first_value();
+        second_value();
       };
     } else {
       return first;
diff --git a/tests/tinytest_test.cpp b/tests/tinytest_test.cpp
index 0046216..3dae7c0 100644
--- a/tests/tinytest_test.cpp
+++ b/tests/tinytest_test.cpp
@@ -441,9 +441,9 @@ TEST(TestSuite, ShouldCoerceValuesToTheCorrectTypes) {
   EXPECT_THAT(get<0>(test_data), Eq("Test Name"));
   EXPECT_THAT(get<1>(test_data), Eq("Expected"));
   // Item 2 is checked below as inputs.
-  EXPECT_THAT(get<3>(test_data), Ne(nullopt));
-  EXPECT_THAT(get<4>(test_data), Ne(nullopt));
-  EXPECT_THAT(get<5>(test_data), Ne(nullopt));
+  EXPECT_THAT(get<3>(test_data).has_value(), Eq(false));
+  EXPECT_THAT(get<4>(test_data).has_value(), Eq(false));
+  EXPECT_THAT(get<5>(test_data).has_value(), Eq(false));
   EXPECT_THAT(get<6>(test_data), Eq(false));
 
   auto inputs = get<2>(test_data);
@@ -481,9 +481,9 @@ TEST(MakeTestSuite, ShouldMakeATestSuiteWithAVectorOfTestRuns) {
   EXPECT_THAT(get<0>(test_data), Eq("Test Name"));
   EXPECT_THAT(get<1>(test_data), Eq("Expected"));
   // Item 2 is checked below as inputs.
-  EXPECT_THAT(get<3>(test_data), Ne(nullopt));
-  EXPECT_THAT(get<4>(test_data), Ne(nullopt));
-  EXPECT_THAT(get<5>(test_data), Ne(nullopt));
+  EXPECT_THAT(get<3>(test_data).has_value(), Eq(false));
+  EXPECT_THAT(get<4>(test_data).has_value(), Eq(false));
+  EXPECT_THAT(get<5>(test_data).has_value(), Eq(false));
   EXPECT_THAT(get<6>(test_data), Eq(false));
 
   auto inputs = get<2>(test_data);
@@ -512,18 +512,18 @@ TEST(MakeTestSuite, ShouldMakeATestSuiteWithAnInitializerListOfTestRuns) {
   EXPECT_THAT(get<0>(first), Eq("Suite Two"));
   // EXPECT_THAT(get<1>(first), Eq(fnToTest));
   EXPECT_THAT(get<2>(first).size(), Eq(1));
-  EXPECT_THAT(get<3>(first), Ne(nullopt));
-  EXPECT_THAT(get<4>(first), Ne(nullopt));
-  EXPECT_THAT(get<5>(first), Ne(nullopt));
+  EXPECT_THAT(get<3>(first).has_value(), Eq(true));
+  EXPECT_THAT(get<4>(first).has_value(), Eq(true));
+  EXPECT_THAT(get<5>(first).has_value(), Eq(true));
   EXPECT_THAT(get<6>(first), Eq(true));
 
   auto test_data = *get<2>(first).begin();
   EXPECT_THAT(get<0>(test_data), Eq("Test Name"));
   EXPECT_THAT(get<1>(test_data), Eq("Expected"));
   // Item 2 is checked below as inputs.
-  EXPECT_THAT(get<3>(test_data), Ne(nullopt));
-  EXPECT_THAT(get<4>(test_data), Ne(nullopt));
-  EXPECT_THAT(get<5>(test_data), Ne(nullopt));
+  EXPECT_THAT(get<3>(test_data).has_value(), Eq(false));
+  EXPECT_THAT(get<4>(test_data).has_value(), Eq(false));
+  EXPECT_THAT(get<5>(test_data).has_value(), Eq(false));
   EXPECT_THAT(get<6>(test_data), Eq(false));
 
   auto inputs = get<2>(test_data);