Auto merge of #12327 - malisas:profile-stats, r=jdm

Profile stats

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Pulled out profiler statistics calculation into its own function in time.rs, added tests for it, and simplified min and max calculation for pre-sorted data.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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tests/unit/profile/time.rs

@@ -15,3 +15,40 @@ fn time_profiler_smoke_test() {
     chan.send(ProfilerMsg::Exit(ipcchan));
     assert!(true, "Can tell the profiler thread to exit");
 }
+
+#[test]
+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);
+
+    assert_eq!(7.34230845, even_mean);
+    assert_eq!(7.345, even_median);
+    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,
+                        9.2345, 10.2342345, 13.2599];
+    let (odd_mean, odd_median, odd_min, odd_max) = time::Profiler::get_statistics(&odd_data);
+
+    assert_eq!(6.491453833333334, odd_mean);
+    assert_eq!(5.324, odd_median);
+    assert_eq!(1.234, odd_min);
+    assert_eq!(13.2599, odd_max);
+}
+
+#[cfg(debug_assertions)]
+#[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);
+}
+
+#[cfg(debug_assertions)]
+#[test]
+#[should_panic]
+fn time_profiler_data_len_zero() {
+    let zero_data = vec![];
+    time::Profiler::get_statistics(&zero_data);
+}