diff --git a/include/snapshot/snapshot.h b/include/snapshot/snapshot.h
index 77451ad..6e346bf 100644
--- a/include/snapshot/snapshot.h
+++ b/include/snapshot/snapshot.h
@@ -447,17 +447,14 @@ class Snapshot {
 
         const auto before_content = StringUtility::ToString(before);
         const auto after_content = StringUtility::ToString(after);
-        const auto before_content_target_file =
-                StringUtility::Join({"/tmp", getSnapshotDiffBeforeFilename(filename_split.back())}, '/');
-        const auto after_content_target_file =
-                StringUtility::Join({"/tmp", getSnapshotDiffAfterFilename(filename_split.back())}, '/');
+        const auto before_content_target_file = StringUtility::Join(
+                {"/tmp", getSnapshotDiffBeforeFilename(StringUtility::Split(snapshot_key, '/').back())}, '/');
+        const auto after_content_target_file = StringUtility::Join(
+                {"/tmp", getSnapshotDiffAfterFilename(StringUtility::Split(snapshot_key, '/').back())}, '/');
 
         FileUtility::RewriteFile(before_content_target_file, before_content);
         FileUtility::RewriteFile(after_content_target_file, after_content);
 
-        std::cout << before_content_target_file << std::endl;
-        std::cout << after_content_target_file << std::endl;
-
         const auto diff_content = SystemUtility::Diff(before_content_target_file, after_content_target_file);
 
         FileUtility::RemoveFile(before_content_target_file);
diff --git a/test/file_utility_test.cc b/test/file_utility_test.cc
index bb52cc4..2e71a7c 100644
--- a/test/file_utility_test.cc
+++ b/test/file_utility_test.cc
@@ -10,4 +10,14 @@ class FileUtilityTest : public testing::Test {
 public:
 };
 
-TEST_F(FileUtilityTest, get_all_lines) {}
+TEST_F(FileUtilityTest, get_all_lines) {
+    const std::string a = R"(
+        "foo": bar
+    )";
+
+    const std::string b = R"(
+        "foo": bar2
+    )";
+
+    SNAPSHOT_DIFF(a, b);
+}