Ensure Of is always valid

Author: pitdicker

src/naive/date.rs

@@ -242,19 +242,29 @@ impl NaiveDate {
     pub(crate) fn weeks_from(&self, day: Weekday) -> i32 {
         (self.ordinal() as i32 - self.weekday().num_days_from(day) as i32 + 6) / 7
     }
-    /// Makes a new `NaiveDate` from year and packed ordinal-flags, with a verification.
-    fn from_of(year: i32, of: Of) -> Option<NaiveDate> {
-        if (MIN_YEAR..=MAX_YEAR).contains(&year) && of.valid() {
-            let Of(of) = of;
-            Some(NaiveDate { ymdf: (year << 13) | (of as DateImpl) })
-        } else {
-            None
+
+    /// Makes a new `NaiveDate` from year, ordinal and flags.
+    /// Does not check whether the flags are correct for the provided year.
+    const fn from_of(year: i32, ordinal: u32, flags: YearFlags) -> Option<NaiveDate> {
+        if year < MIN_YEAR || year > MAX_YEAR {
+            return None; // Out-of-range
+        }
+        match Of::new(ordinal, flags) {
+            Some(of) => Some(NaiveDate { ymdf: (year << 13) | (of.inner() as DateImpl) }),
+            None => None, // Invalid: Ordinal outside of the nr of days in a year with those flags.
         }
     }
 
-    /// Makes a new `NaiveDate` from year and packed month-day-flags, with a verification.
-    fn from_mdf(year: i32, mdf: Mdf) -> Option<NaiveDate> {
-        NaiveDate::from_of(year, mdf.to_of())
+    /// Makes a new `NaiveDate` from year and packed month-day-flags.
+    /// Does not check whether the flags are correct for the provided year.
+    const fn from_mdf(year: i32, mdf: Mdf) -> Option<NaiveDate> {
+        if year < MIN_YEAR || year > MAX_YEAR {
+            return None; // Out-of-range
+        }
+        match mdf.to_of() {
+            Some(of) => Some(NaiveDate { ymdf: (year << 13) | (of.inner() as DateImpl) }),
+            None => None, // Non-existing date
+        }
     }
 
     /// Makes a new `NaiveDate` from the [calendar date](#calendar-date)
@@ -325,7 +335,7 @@ impl NaiveDate {
     #[must_use]
     pub fn from_yo_opt(year: i32, ordinal: u32) -> Option<NaiveDate> {
         let flags = YearFlags::from_year(year);
-        NaiveDate::from_of(year, Of::new(ordinal, flags)?)
+        NaiveDate::from_of(year, ordinal, flags)
     }
 
     /// Makes a new `NaiveDate` from the [ISO week date](#week-date)
@@ -394,20 +404,17 @@ impl NaiveDate {
             if weekord <= delta {
                 // ordinal < 1, previous year
                 let prevflags = YearFlags::from_year(year - 1);
-                NaiveDate::from_of(
-                    year - 1,
-                    Of::new(weekord + prevflags.ndays() - delta, prevflags)?,
-                )
+                NaiveDate::from_of(year - 1, weekord + prevflags.ndays() - delta, prevflags)
             } else {
                 let ordinal = weekord - delta;
                 let ndays = flags.ndays();
                 if ordinal <= ndays {
                     // this year
-                    NaiveDate::from_of(year, Of::new(ordinal, flags)?)
+                    NaiveDate::from_of(year, ordinal, flags)
                 } else {
                     // ordinal > ndays, next year
                     let nextflags = YearFlags::from_year(year + 1);
-                    NaiveDate::from_of(year + 1, Of::new(ordinal - ndays, nextflags)?)
+                    NaiveDate::from_of(year + 1, ordinal - ndays, nextflags)
                 }
             }
         } else {
@@ -452,7 +459,7 @@ impl NaiveDate {
         let (year_div_400, cycle) = div_mod_floor(days, 146_097);
         let (year_mod_400, ordinal) = internals::cycle_to_yo(cycle as u32);
         let flags = YearFlags::from_year_mod_400(year_mod_400 as i32);
-        NaiveDate::from_of(year_div_400 * 400 + year_mod_400 as i32, Of::new(ordinal, flags)?)
+        NaiveDate::from_of(year_div_400 * 400 + year_mod_400 as i32, ordinal, flags)
     }
 
     /// Makes a new `NaiveDate` by counting the number of occurrences of a particular day-of-week
@@ -925,28 +932,24 @@ impl NaiveDate {
     /// Returns the packed ordinal-flags.
     #[inline]
     const fn of(&self) -> Of {
-        Of((self.ymdf & 0b1_1111_1111_1111) as u32)
+        Of::from_date_impl(self.ymdf)
     }
 
     /// Makes a new `NaiveDate` with the packed month-day-flags changed.
     ///
     /// Returns `None` when the resulting `NaiveDate` would be invalid.
     #[inline]
     fn with_mdf(&self, mdf: Mdf) -> Option<NaiveDate> {
-        self.with_of(mdf.to_of())
+        Some(self.with_of(mdf.to_of()?))
     }
 
     /// Makes a new `NaiveDate` with the packed ordinal-flags changed.
     ///
     /// Returns `None` when the resulting `NaiveDate` would be invalid.
+    /// Does not check if the year flags match the year.
     #[inline]
-    fn with_of(&self, of: Of) -> Option<NaiveDate> {
-        if of.valid() {
-            let Of(of) = of;
-            Some(NaiveDate { ymdf: (self.ymdf & !0b1_1111_1111_1111) | of as DateImpl })
-        } else {
-            None
-        }
+    const fn with_of(&self, of: Of) -> NaiveDate {
+        NaiveDate { ymdf: (self.ymdf & !0b1_1111_1111_1111) | of.inner() as DateImpl }
     }
 
     /// Makes a new `NaiveDate` for the next calendar date.
@@ -975,7 +978,10 @@ impl NaiveDate {
     #[inline]
     #[must_use]
     pub fn succ_opt(&self) -> Option<NaiveDate> {
-        self.with_of(self.of().succ()).or_else(|| NaiveDate::from_ymd_opt(self.year() + 1, 1, 1))
+        match self.of().succ() {
+            Some(of) => Some(self.with_of(of)),
+            None => NaiveDate::from_ymd_opt(self.year() + 1, 1, 1),
+        }
     }
 
     /// Makes a new `NaiveDate` for the previous calendar date.
@@ -1004,7 +1010,10 @@ impl NaiveDate {
     #[inline]
     #[must_use]
     pub fn pred_opt(&self) -> Option<NaiveDate> {
-        self.with_of(self.of().pred()).or_else(|| NaiveDate::from_ymd_opt(self.year() - 1, 12, 31))
+        match self.of().pred() {
+            Some(of) => Some(self.with_of(of)),
+            None => NaiveDate::from_ymd_opt(self.year() - 1, 12, 31),
+        }
     }
 
     /// Adds the `days` part of given `Duration` to the current date.
@@ -1036,7 +1045,7 @@ impl NaiveDate {
 
         let (year_mod_400, ordinal) = internals::cycle_to_yo(cycle as u32);
         let flags = YearFlags::from_year_mod_400(year_mod_400 as i32);
-        NaiveDate::from_of(year_div_400 * 400 + year_mod_400 as i32, Of::new(ordinal, flags)?)
+        NaiveDate::from_of(year_div_400 * 400 + year_mod_400 as i32, ordinal, flags)
     }
 
     /// Subtracts the `days` part of given `Duration` from the current date.
@@ -1068,7 +1077,7 @@ impl NaiveDate {
 
         let (year_mod_400, ordinal) = internals::cycle_to_yo(cycle as u32);
         let flags = YearFlags::from_year_mod_400(year_mod_400 as i32);
-        NaiveDate::from_of(year_div_400 * 400 + year_mod_400 as i32, Of::new(ordinal, flags)?)
+        NaiveDate::from_of(year_div_400 * 400 + year_mod_400 as i32, ordinal, flags)
     }
 
     /// Subtracts another `NaiveDate` from the current date.
@@ -1623,7 +1632,7 @@ impl Datelike for NaiveDate {
     /// ```
     #[inline]
     fn with_ordinal(&self, ordinal: u32) -> Option<NaiveDate> {
-        self.with_of(self.of().with_ordinal(ordinal)?)
+        self.of().with_ordinal(ordinal).map(|of| self.with_of(of))
     }
 
     /// Makes a new `NaiveDate` with the day of year (starting from 0) changed.
@@ -1648,7 +1657,7 @@ impl Datelike for NaiveDate {
     #[inline]
     fn with_ordinal0(&self, ordinal0: u32) -> Option<NaiveDate> {
         let ordinal = ordinal0.checked_add(1)?;
-        self.with_of(self.of().with_ordinal(ordinal)?)
+        self.with_ordinal(ordinal)
     }
 }