deduplicate: zero elements when a slice is shortened

slicetools/deduplicate.go

@@ -33,5 +33,12 @@ func Deduplicate[T comparable](slice []T) []T {
 			j++
 		}
 	}
+
+	// Zero elements from j to len(slice), like stdlib methods
+	var zero T // Default zero value for type T
+	for i := j; i < len(slice); i++ {
+		slice[i] = zero
+	}
+
 	return slice[:j]
 }

slicetools/deduplicate_test.go

@@ -33,6 +33,9 @@ func TestUniqueIntegers(t *testing.T) {
 			if len(got) > 0 {
 				assert.Equal(t, got, tc.slice[:len(got)], "Deduplicate should modify the original slice!")
 			}
+			for i := len(got); i < len(tc.slice); i++ {
+				assert.Equal(t, 0, tc.slice[i], "Deduplicate should zero out the remaining elements!")
+			}
 		})
 	}
 }