diff --git a/src/test/erase/pattern_test.cpp b/src/test/erase/pattern_test.cpp
index 0244f8a..0693163 100644
--- a/src/test/erase/pattern_test.cpp
+++ b/src/test/erase/pattern_test.cpp
@@ -168,25 +168,27 @@
     auto shortData = std::vector<std::byte>(shortSize, std::byte{0});
     auto restOfData =
         std::vector<std::byte>(size - shortSize * 3, std::byte{0});
+    std::span shortDataSpan{shortData};
+    std::span restOfDataSpan{restOfData};
     // open the file and write none to it
 
     stdplus::fd::FdMock mock;
 
     // test writes
     EXPECT_CALL(mock, write(_))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(restOfData))
-        .WillOnce(Return(restOfData)); // return too much data!
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(restOfDataSpan))
+        .WillOnce(Return(restOfDataSpan)); // return too much data!
 
     EXPECT_THROW(tryPattern.writePattern(size, mock), InternalFailure);
 
     // test reads
     EXPECT_CALL(mock, read(_))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(restOfData))
-        .WillOnce(Return(restOfData)); // return too much data!
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(restOfDataSpan))
+        .WillOnce(Return(restOfDataSpan)); // return too much data!
 
     EXPECT_THROW(tryPattern.verifyPattern(size, mock), InternalFailure);
 }
@@ -204,7 +206,7 @@
     // test writes
     EXPECT_CALL(mocks, write(_))
         .Times(33)
-        .WillRepeatedly(Return(std::vector<std::byte>{}))
+        .WillRepeatedly(Return(std::span<std::byte>{}))
         .RetiresOnSaturation();
 
     EXPECT_THROW(tryPattern.writePattern(size, mocks), InternalFailure);
@@ -212,7 +214,7 @@
     // test reads
     EXPECT_CALL(mocks, read(_))
         .Times(33)
-        .WillRepeatedly(Return(std::vector<std::byte>{}))
+        .WillRepeatedly(Return(std::span<std::byte>{}))
         .RetiresOnSaturation();
 
     EXPECT_THROW(tryPattern.verifyPattern(size, mocks), InternalFailure);
diff --git a/src/test/erase/zero_test.cpp b/src/test/erase/zero_test.cpp
index b14d546..8570154 100644
--- a/src/test/erase/zero_test.cpp
+++ b/src/test/erase/zero_test.cpp
@@ -128,23 +128,25 @@
     auto shortData = std::vector<std::byte>(shortSize, std::byte{0});
     auto restOfData =
         std::vector<std::byte>(size - shortSize * 3, std::byte{0});
+    std::span shortDataSpan{shortData};
+    std::span restOfDataSpan{restOfData};
     stdplus::fd::FdMock mock;
 
     // test write zeros with short blocks
     EXPECT_CALL(mock, write(_))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(restOfData))
-        .WillOnce(Return(shortData));
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(restOfDataSpan))
+        .WillOnce(Return(shortDataSpan));
 
     EXPECT_NO_THROW(pass.writeZero(size, mock));
 
     // test read zeros with short blocks
     EXPECT_CALL(mock, read(_))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(restOfData))
-        .WillOnce(Return(shortData));
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(restOfDataSpan))
+        .WillOnce(Return(shortDataSpan));
 
     EXPECT_NO_THROW(pass.verifyZero(size, mock));
 }
@@ -159,25 +161,27 @@
     auto shortData = std::vector<std::byte>(shortSize, std::byte{0});
     auto restOfData =
         std::vector<std::byte>(size - shortSize * 3, std::byte{0});
+    std::span shortDataSpan{shortData};
+    std::span restOfDataSpan{restOfData};
     // open the file and write none zero to it
 
     stdplus::fd::FdMock mock;
 
     // test writes
     EXPECT_CALL(mock, write(_))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(restOfData))
-        .WillOnce(Return(restOfData)); // return too much data!
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(restOfDataSpan))
+        .WillOnce(Return(restOfDataSpan)); // return too much data!
 
     EXPECT_THROW(tryZero.writeZero(size, mock), InternalFailure);
 
     // test reads
     EXPECT_CALL(mock, read(_))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(shortData))
-        .WillOnce(Return(restOfData))
-        .WillOnce(Return(restOfData)); // return too much data!
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(shortDataSpan))
+        .WillOnce(Return(restOfDataSpan))
+        .WillOnce(Return(restOfDataSpan)); // return too much data!
 
     EXPECT_THROW(tryZero.verifyZero(size, mock), InternalFailure);
 }
@@ -195,13 +199,13 @@
     // test writes
     EXPECT_CALL(mocks, write(_))
         .Times(33)
-        .WillRepeatedly(Return(std::vector<std::byte>{}))
+        .WillRepeatedly(Return(std::span<std::byte>{}))
         .RetiresOnSaturation();
     EXPECT_THROW(tryZero.writeZero(size, mocks), InternalFailure);
     // test reads
     EXPECT_CALL(mocks, read(_))
         .Times(33)
-        .WillRepeatedly(Return(std::vector<std::byte>{}))
+        .WillRepeatedly(Return(std::span<std::byte>{}))
         .RetiresOnSaturation();
     EXPECT_THROW(tryZero.verifyZero(size, mocks), InternalFailure);
 }