1 files changed, 164 insertions, 0 deletions
diff --git a/third_party/rust/time/src/month.rs b/third_party/rust/time/src/month.rs
new file mode 100644
index 0000000000..0c657e9821
--- /dev/null
+++ b/third_party/rust/time/src/month.rs
@@ -0,0 +1,164 @@
+//! The `Month` enum and its associated `impl`s.
+
+use core::fmt;
+use core::num::NonZeroU8;
+use core::str::FromStr;
+
+use self::Month::*;
+use crate::error;
+
+/// Months of the year.
+#[allow(clippy::missing_docs_in_private_items)] // variants
+#[repr(u8)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum Month {
+    January = 1,
+    February = 2,
+    March = 3,
+    April = 4,
+    May = 5,
+    June = 6,
+    July = 7,
+    August = 8,
+    September = 9,
+    October = 10,
+    November = 11,
+    December = 12,
+}
+
+impl Month {
+    /// Create a `Month` from its numerical value.
+    pub(crate) const fn from_number(n: NonZeroU8) -> Result<Self, error::ComponentRange> {
+        match n.get() {
+            1 => Ok(January),
+            2 => Ok(February),
+            3 => Ok(March),
+            4 => Ok(April),
+            5 => Ok(May),
+            6 => Ok(June),
+            7 => Ok(July),
+            8 => Ok(August),
+            9 => Ok(September),
+            10 => Ok(October),
+            11 => Ok(November),
+            12 => Ok(December),
+            n => Err(error::ComponentRange {
+                name: "month",
+                minimum: 1,
+                maximum: 12,
+                value: n as _,
+                conditional_range: false,
+            }),
+        }
+    }
+
+    /// Get the previous month.
+    ///
+    /// ```rust
+    /// # use time::Month;
+    /// assert_eq!(Month::January.previous(), Month::December);
+    /// ```
+    pub const fn previous(self) -> Self {
+        match self {
+            January => December,
+            February => January,
+            March => February,
+            April => March,
+            May => April,
+            June => May,
+            July => June,
+            August => July,
+            September => August,
+            October => September,
+            November => October,
+            December => November,
+        }
+    }
+
+    /// Get the next month.
+    ///
+    /// ```rust
+    /// # use time::Month;
+    /// assert_eq!(Month::January.next(), Month::February);
+    /// ```
+    pub const fn next(self) -> Self {
+        match self {
+            January => February,
+            February => March,
+            March => April,
+            April => May,
+            May => June,
+            June => July,
+            July => August,
+            August => September,
+            September => October,
+            October => November,
+            November => December,
+            December => January,
+        }
+    }
+}
+
+impl fmt::Display for Month {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.write_str(match self {
+            January => "January",
+            February => "February",
+            March => "March",
+            April => "April",
+            May => "May",
+            June => "June",
+            July => "July",
+            August => "August",
+            September => "September",
+            October => "October",
+            November => "November",
+            December => "December",
+        })
+    }
+}
+
+impl FromStr for Month {
+    type Err = error::InvalidVariant;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "January" => Ok(January),
+            "February" => Ok(February),
+            "March" => Ok(March),
+            "April" => Ok(April),
+            "May" => Ok(May),
+            "June" => Ok(June),
+            "July" => Ok(July),
+            "August" => Ok(August),
+            "September" => Ok(September),
+            "October" => Ok(October),
+            "November" => Ok(November),
+            "December" => Ok(December),
+            _ => Err(error::InvalidVariant),
+        }
+    }
+}
+
+impl From<Month> for u8 {
+    fn from(month: Month) -> Self {
+        month as _
+    }
+}
+
+impl TryFrom<u8> for Month {
+    type Error = error::ComponentRange;
+
+    fn try_from(value: u8) -> Result<Self, Self::Error> {
+        match NonZeroU8::new(value) {
+            Some(value) => Self::from_number(value),
+            None => Err(error::ComponentRange {
+                name: "month",
+                minimum: 1,
+                maximum: 12,
+                value: 0,
+                conditional_range: false,
+            }),
+        }
+    }
+}