diff --git a/Cargo.toml b/Cargo.toml
index 8db7f5469..f75249785 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -57,7 +57,7 @@ chrono = "0.4"
 winapi = "0.3"
 
 [dev-dependencies]
-rand = "0.6"
+rand = "0.7"
 maplit = "1"
 matches = "0.1.8"
 time = "0.1.42"
diff --git a/src/lib.rs b/src/lib.rs
index 6e7e34e67..5f3231d04 100755
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -342,7 +342,7 @@ mod tests {
 
     pub fn sample_with_seed(n: u32, ratio: f64, seed_val: u8) -> Vec<u32> {
         StdRng::from_seed([seed_val; 32])
-            .sample_iter(&Bernoulli::new(ratio))
+            .sample_iter(&Bernoulli::new(ratio).unwrap())
             .take(n as usize)
             .enumerate()
             .filter_map(|(val, keep)| if keep { Some(val as u32) } else { None })