diff --git a/tsdb/db_test.go b/tsdb/db_test.go
index a9c7dee75..770b1a1b4 100644
--- a/tsdb/db_test.go
+++ b/tsdb/db_test.go
@@ -5469,7 +5469,9 @@ func testWBLAndMmapReplay(t *testing.T, scenario sampleTypeScenario) {
 		chk, err := db.head.chunkDiskMapper.Chunk(mc.ref)
 		require.NoError(t, err)
 		it := chk.Iterator(nil)
-		s1MmapSamples = append(s1MmapSamples, samplesFromIterator(t, it)...)
+		smpls, err := storage.ExpandSamples(it, newSample)
+		require.NoError(t, err)
+		s1MmapSamples = append(s1MmapSamples, smpls...)
 	}
 	require.NotEmpty(t, s1MmapSamples)
 
diff --git a/tsdb/ooo_head_read_test.go b/tsdb/ooo_head_read_test.go
index ed9a9f88c..938f9a7f7 100644
--- a/tsdb/ooo_head_read_test.go
+++ b/tsdb/ooo_head_read_test.go
@@ -847,7 +847,8 @@ func testOOOHeadChunkReader_Chunk(t *testing.T, scenario sampleTypeScenario) {
 				require.Nil(t, c)
 
 				it := iterable.Iterator(nil)
-				resultSamples := samplesFromIterator(t, it)
+				resultSamples, err := storage.ExpandSamples(it, nil)
+				require.NoError(t, err)
 				requireEqualSamples(t, s1.String(), tc.expChunksSamples[i], resultSamples, true)
 			}
 		})
@@ -1041,7 +1042,8 @@ func testOOOHeadChunkReader_Chunk_ConsistentQueryResponseDespiteOfHeadExpanding(
 				require.Nil(t, c)
 
 				it := iterable.Iterator(nil)
-				resultSamples := samplesFromIterator(t, it)
+				resultSamples, err := storage.ExpandSamples(it, nil)
+				require.NoError(t, err)
 				requireEqualSamples(t, s1.String(), tc.expChunksSamples[i], resultSamples, true)
 			}
 		})
diff --git a/tsdb/testutil.go b/tsdb/testutil.go
index 3f7df2d3a..71c54761e 100644
--- a/tsdb/testutil.go
+++ b/tsdb/testutil.go
@@ -18,8 +18,6 @@ import (
 
 	prom_testutil "github.com/prometheus/client_golang/prometheus/testutil"
 
-	"github.com/prometheus/prometheus/tsdb/chunkenc"
-
 	"github.com/stretchr/testify/require"
 
 	"github.com/prometheus/prometheus/model/histogram"
@@ -156,7 +154,9 @@ func requireEqualSamples(t *testing.T, name string, expected, actual []chunks.Sa
 				require.Equal(t, expectedHist, actualHist, "Sample doesn't match for %s[%d] at ts %d", name, i, expectedSample.T())
 			}
 		default:
-			require.Equal(t, expectedSample, actualSample, "Sample doesn't match for %s[%d] at ts %d", name, i, expectedSample.T())
+			expectedFloat := expectedSample.F()
+			actualFloat := actualSample.F()
+			require.Equal(t, expectedFloat, actualFloat, "Sample doesn't match for %s[%d] at ts %d", name, i, expectedSample.T())
 		}
 	}
 }
@@ -174,23 +174,3 @@ func counterResetAsString(h histogram.CounterResetHint) string {
 	}
 	panic("Unexpected counter reset type")
 }
-
-func samplesFromIterator(t testing.TB, it chunkenc.Iterator) []chunks.Sample {
-	var samples []chunks.Sample
-	for typ := it.Next(); typ != chunkenc.ValNone; typ = it.Next() {
-		switch typ {
-		case chunkenc.ValFloat:
-			ts, val := it.At()
-			samples = append(samples, sample{t: ts, f: val})
-		case chunkenc.ValHistogram:
-			ts, val := it.AtHistogram(nil)
-			samples = append(samples, sample{t: ts, h: val})
-		case chunkenc.ValFloatHistogram:
-			ts, val := it.AtFloatHistogram(nil)
-			samples = append(samples, sample{t: ts, fh: val})
-		default:
-			t.Fatalf("unknown sample value type %s", typ)
-		}
-	}
-	return samples
-}