fix(sentry-types): Switch to checked version of from_secs_f64 (#554)

This change make use of `try_from_secs_f64` (the checked version of `from_secs_f64`),
avoiding panics if the incoming seconds is negative, overflows Duration or not finite.

sentry-types/src/utils.rs

@@ -13,7 +13,7 @@ pub fn datetime_to_timestamp(st: &SystemTime) -> f64 {
 }
 
 pub fn timestamp_to_datetime(ts: f64) -> Option<SystemTime> {
-    let duration = Duration::from_secs_f64(ts);
+    let duration = Duration::try_from_secs_f64(ts).ok()?;
     SystemTime::UNIX_EPOCH.checked_add(duration)
 }
 
@@ -188,3 +188,16 @@ pub mod ts_rfc3339_opt {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::timestamp_to_datetime;
+
+    #[test]
+    fn test_timestamp_to_datetime() {
+        assert!(timestamp_to_datetime(-10000.0).is_none());
+        assert!(timestamp_to_datetime(f64::INFINITY).is_none());
+        assert!(timestamp_to_datetime(f64::MAX).is_none());
+        assert!(timestamp_to_datetime(123123123.0).is_some());
+    }
+}