fix: check overflows during date time composition

Author: yuankunzhang

src/items/mod.rs

@@ -356,7 +356,7 @@ fn at_date_inner(date: Vec<Item>, at: DateTime<FixedOffset>) -> Option<DateTime<
                 let delta = (day.num_days_from_monday() as i32
                     - d.weekday().num_days_from_monday() as i32)
                     .rem_euclid(7)
-                    + x * 7;
+                    + x.checked_mul(7)?;
 
                 d = if delta < 0 {
                     d.checked_sub_days(chrono::Days::new((-delta) as u64))?
@@ -394,11 +394,11 @@ fn at_date_inner(date: Vec<Item>, at: DateTime<FixedOffset>) -> Option<DateTime<
                     relative::Relative::Days(x) => d += chrono::Duration::days(x.into()),
                     relative::Relative::Hours(x) => d += chrono::Duration::hours(x.into()),
                     relative::Relative::Minutes(x) => {
-                        d += chrono::Duration::minutes(x.into());
+                        d += chrono::Duration::try_minutes(x.into())?;
                     }
                     // Seconds are special because they can be given as a float
                     relative::Relative::Seconds(x) => {
-                        d += chrono::Duration::seconds(x as i64);
+                        d += chrono::Duration::try_seconds(x as i64)?;
                     }
                 }
             }

src/items/relative.rs

@@ -54,13 +54,15 @@ pub enum Relative {
 }
 
 impl Relative {
+    // TODO: determine how to handle multiplication overflows,
+    // using saturating_mul for now.
     fn mul(self, n: i32) -> Self {
         match self {
-            Self::Years(x) => Self::Years(n * x),
-            Self::Months(x) => Self::Months(n * x),
-            Self::Days(x) => Self::Days(n * x),
-            Self::Hours(x) => Self::Hours(n * x),
-            Self::Minutes(x) => Self::Minutes(n * x),
+            Self::Years(x) => Self::Years(n.saturating_mul(x)),
+            Self::Months(x) => Self::Months(n.saturating_mul(x)),
+            Self::Days(x) => Self::Days(n.saturating_mul(x)),
+            Self::Hours(x) => Self::Hours(n.saturating_mul(x)),
+            Self::Minutes(x) => Self::Minutes(n.saturating_mul(x)),
             Self::Seconds(x) => Self::Seconds(f64::from(n) * x),
         }
     }