added test and assertion that profiler statistics data must be sorted

servo · Jul 7, 2016 · 7dccf09 · 7dccf09
1 parent d47b769
commit 7dccf09
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Showing 2 changed files with 22 additions and 9 deletions.
diff --git a/components/profile/time.rs b/components/profile/time.rs
@@ -328,12 +328,17 @@ impl Profiler {
     }
 
     pub fn get_statistics(data: &[f64]) -> (f64, f64, f64, f64) {
-         let data_len = data.len();
-         let (mean, median, min, max) =
-             (data.iter().sum::<f64>() / (data_len as f64),
-             data[data_len / 2],
-             data.iter().fold(f64::INFINITY, |a, &b| a.min(b)),
-             data.iter().fold(-f64::INFINITY, |a, &b| a.max(b)));
+        data.iter().fold(-f64::INFINITY, |a, &b| {
+            debug_assert!(a < b, "Data must be sorted");
+            b
+        });
+
+        let data_len = data.len();
+        let (mean, median, min, max) =
+            (data.iter().sum::<f64>() / (data_len as f64),
+            data[data_len / 2],
+            data.iter().fold(f64::INFINITY, |a, &b| a.min(b)),
+            data.iter().fold(-f64::INFINITY, |a, &b| a.max(b)));
         (mean, median, min, max)
     }
 

diff --git a/tests/unit/profile/time.rs b/tests/unit/profile/time.rs
@@ -17,8 +17,8 @@ fn time_profiler_smoke_test() {
 }
 
 #[test]
-fn time_profilers_stats_test() {
-    let even_data = vec![1.234, 3.24567, 3.54578, 5.0, 5.324, 7.345, \
+fn time_profiler_stats_test() {
+    let even_data = vec![1.234, 3.24567, 3.54578, 5.0, 5.324, 7.345,
                          9.2345, 10.2342345, 13.2599, 15.0];
     let (even_mean, even_median, even_min, even_max) = time::Profiler::get_statistics(&even_data);
 
@@ -27,7 +27,7 @@ fn time_profilers_stats_test() {
     assert_eq!(1.234, even_min);
     assert_eq!(15.0, even_max);
 
-    let odd_data = vec![1.234, 3.24567, 3.54578, 5.0, 5.324, 7.345, \
+    let odd_data = vec![1.234, 3.24567, 3.54578, 5.0, 5.324, 7.345,
                         9.2345, 10.2342345, 13.2599];
     let (odd_mean, odd_median, odd_min, odd_max) = time::Profiler::get_statistics(&odd_data);
 
@@ -36,3 +36,11 @@ fn time_profilers_stats_test() {
     assert_eq!(1.234, odd_min);
     assert_eq!(13.2599, odd_max);
 }
+
+#[cfg(debug)]
+#[test]
+#[should_panic]
+fn time_profiler_unsorted_stats_test() {
+    let unsorted_data = vec![5.0, 7.5, 1.0, 8.9];
+    time::Profiler::get_statistics(&unsorted_data);
+}