diff --git a/src/clang_indexer.cc b/src/clang_indexer.cc
index f8950eac..489eed31 100644
--- a/src/clang_indexer.cc
+++ b/src/clang_indexer.cc
@@ -2153,7 +2153,7 @@ void OnIndexReference(CXClientData client_data, const CXIdxEntityRefInfo* ref) {
   }
 }
 
-std::optional<std::vector<std::unique_ptr<IndexFile>>> Parse(
+std::vector<std::unique_ptr<IndexFile>> Parse(
     Config* config,
     FileConsumerSharedState* file_consumer_shared,
     std::string file,
@@ -2163,7 +2163,7 @@ std::optional<std::vector<std::unique_ptr<IndexFile>>> Parse(
     ClangIndex* index,
     bool dump_ast) {
   if (!config->index.enabled)
-    return std::nullopt;
+    return {};
 
   file = NormalizePath(file);
 
@@ -2183,7 +2183,7 @@ std::optional<std::vector<std::unique_ptr<IndexFile>>> Parse(
       CXTranslationUnit_KeepGoing |
           CXTranslationUnit_DetailedPreprocessingRecord);
   if (!tu)
-    return std::nullopt;
+    return {};
 
   perf->index_parse = timer.ElapsedMicrosecondsAndReset();
 
@@ -2194,7 +2194,7 @@ std::optional<std::vector<std::unique_ptr<IndexFile>>> Parse(
                      args, unsaved_files);
 }
 
-std::optional<std::vector<std::unique_ptr<IndexFile>>> ParseWithTu(
+std::vector<std::unique_ptr<IndexFile>> ParseWithTu(
     Config* config,
     FileConsumerSharedState* file_consumer_shared,
     PerformanceImportFile* perf,
@@ -2239,7 +2239,7 @@ std::optional<std::vector<std::unique_ptr<IndexFile>>> ParseWithTu(
   if (index_result != CXError_Success) {
     LOG_S(ERROR) << "Indexing " << file
                  << " failed with errno=" << index_result;
-    return std::nullopt;
+    return {};
   }
 
   clang_IndexAction_dispose(index_action);
@@ -2301,7 +2301,7 @@ std::optional<std::vector<std::unique_ptr<IndexFile>>> ParseWithTu(
         entry->dependencies.end());
   }
 
-  return std::move(result);
+  return result;
 }
 
 void ConcatTypeAndName(std::string& type, const std::string& name) {
diff --git a/src/iindexer.cc b/src/iindexer.cc
index 16085bc3..1c77005d 100644
--- a/src/iindexer.cc
+++ b/src/iindexer.cc
@@ -6,7 +6,7 @@ namespace {
 struct ClangIndexer : IIndexer {
   ~ClangIndexer() override = default;
 
-  std::optional<std::vector<std::unique_ptr<IndexFile>>> Index(
+  std::vector<std::unique_ptr<IndexFile>> Index(
       Config* config,
       FileConsumerSharedState* file_consumer_shared,
       std::string file,
@@ -50,7 +50,7 @@ struct TestIndexer : IIndexer {
 
   ~TestIndexer() override = default;
 
-  std::optional<std::vector<std::unique_ptr<IndexFile>>> Index(
+  std::vector<std::unique_ptr<IndexFile>> Index(
       Config* config,
       FileConsumerSharedState* file_consumer_shared,
       std::string file,
@@ -61,14 +61,14 @@ struct TestIndexer : IIndexer {
     if (it == indexes.end()) {
       // Don't return any indexes for unexpected data.
       assert(false && "no indexes");
-      return std::nullopt;
+      return {};
     }
 
     // FIXME: allow user to control how many times we return the index for a
     // specific file (atm it is always 1)
     auto result = std::move(it->second);
     indexes.erase(it);
-    return std::move(result);
+    return result;
   }
 
   std::unordered_map<std::string, std::vector<std::unique_ptr<IndexFile>>>
diff --git a/src/iindexer.h b/src/iindexer.h
index d6648990..df0e2d8b 100644
--- a/src/iindexer.h
+++ b/src/iindexer.h
@@ -34,7 +34,7 @@ struct IIndexer {
       std::initializer_list<TestEntry> entries);
 
   virtual ~IIndexer() = default;
-  virtual std::optional<std::vector<std::unique_ptr<IndexFile>>> Index(
+  virtual std::vector<std::unique_ptr<IndexFile>> Index(
       Config* config,
       FileConsumerSharedState* file_consumer_shared,
       std::string file,
diff --git a/src/import_pipeline.cc b/src/import_pipeline.cc
index 8f53c8c0..9e0eb346 100644
--- a/src/import_pipeline.cc
+++ b/src/import_pipeline.cc
@@ -393,7 +393,7 @@ void ParseFile(Config* config,
   auto indexes = indexer->Index(config, file_consumer_shared, path_to_index,
                                 entry.args, file_contents, &perf);
 
-  if (!indexes) {
+  if (indexes.empty()) {
     if (config->index.enabled &&
         !std::holds_alternative<std::monostate>(request.id)) {
       Out_Error out;
@@ -405,7 +405,7 @@ void ParseFile(Config* config,
     return;
   }
 
-  for (std::unique_ptr<IndexFile>& new_index : *indexes) {
+  for (std::unique_ptr<IndexFile>& new_index : indexes) {
     Timer time;
 
     // Only emit diagnostics for non-interactive sessions, which makes it easier
@@ -556,11 +556,11 @@ void IndexWithTuFromCodeCompletion(
   ClangIndex index;
   auto indexes = ParseWithTu(config, file_consumer_shared, &perf, tu, &index,
                              path, args, file_contents);
-  if (!indexes)
-    return;
+  if (indexes.empty())
+      return;
 
   std::vector<Index_DoIdMap> result;
-  for (std::unique_ptr<IndexFile>& new_index : *indexes) {
+  for (std::unique_ptr<IndexFile>& new_index : indexes) {
     Timer time;
 
     std::shared_ptr<ICacheManager> cache_manager;
diff --git a/src/indexer.h b/src/indexer.h
index e52ddb3d..8857c2bd 100644
--- a/src/indexer.h
+++ b/src/indexer.h
@@ -517,7 +517,7 @@ struct NamespaceHelper {
 // |desired_index_file| is the (h or cc) file which has actually changed.
 // |dependencies| are the existing dependencies of |import_file| if this is a
 // reparse.
-std::optional<std::vector<std::unique_ptr<IndexFile>>> Parse(
+std::vector<std::unique_ptr<IndexFile>> Parse(
     Config* config,
     FileConsumerSharedState* file_consumer_shared,
     std::string file,
@@ -526,7 +526,7 @@ std::optional<std::vector<std::unique_ptr<IndexFile>>> Parse(
     PerformanceImportFile* perf,
     ClangIndex* index,
     bool dump_ast = false);
-std::optional<std::vector<std::unique_ptr<IndexFile>>> ParseWithTu(
+std::vector<std::unique_ptr<IndexFile>> ParseWithTu(
     Config* config,
     FileConsumerSharedState* file_consumer_shared,
     PerformanceImportFile* perf,
diff --git a/src/test.cc b/src/test.cc
index 266ab030..07d083bc 100644
--- a/src/test.cc
+++ b/src/test.cc
@@ -267,7 +267,6 @@ bool RunIndexTests(const std::string& filter_path, bool enable_update) {
     PerformanceImportFile perf;
     auto dbs = Parse(&config, &file_consumer_shared, path, flags, {}, &perf,
                      &index, false /*dump_ast*/);
-    assert(dbs);
 
     for (const auto& entry : all_expected_output) {
       const std::string& expected_path = entry.first;
@@ -298,7 +297,7 @@ bool RunIndexTests(const std::string& filter_path, bool enable_update) {
       };
 
       // Get output from index operation.
-      IndexFile* db = FindDbForPathEnding(expected_path, *dbs);
+      IndexFile* db = FindDbForPathEnding(expected_path, dbs);
       assert(db);
       if (!db->diagnostics_.empty()) {
         std::cout << "For " << path << std::endl;