Merge pull request #195 from cakebaker/bump_version_to_0_11

Bump version to `0.11.0`

Cargo.lock

@@ -71,6 +71,67 @@ version = "0.8.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "773648b94d0e5d620f64f280777445740e61fe701025087ec8b57f45c791888b"
 
+[[package]]
+name = "equivalent"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
+
+[[package]]
+name = "futures-core"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05f29059c0c2090612e8d742178b0580d2dc940c837851ad723096f87af6663e"
+
+[[package]]
+name = "futures-macro"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "162ee34ebcb7c64a8abebc059ce0fee27c2262618d7b60ed8faf72fef13c3650"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "futures-task"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f90f7dce0722e95104fcb095585910c0977252f286e354b5e3bd38902cd99988"
+
+[[package]]
+name = "futures-timer"
+version = "3.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f288b0a4f20f9a56b5d1da57e2227c661b7b16168e2f72365f57b63326e29b24"
+
+[[package]]
+name = "futures-util"
+version = "0.3.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9fa08315bb612088cc391249efdc3bc77536f16c91f6cf495e6fbe85b20a4a81"
+dependencies = [
+ "futures-core",
+ "futures-macro",
+ "futures-task",
+ "pin-project-lite",
+ "pin-utils",
+ "slab",
+]
+
+[[package]]
+name = "glob"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a8d1add55171497b4705a648c6b583acafb01d58050a51727785f0b2c8e0a2b2"
+
+[[package]]
+name = "hashbrown"
+version = "0.15.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5971ac85611da7067dbfcabef3c70ebb5606018acd9e2a3903a0da507521e0d5"
+
 [[package]]
 name = "iana-time-zone"
 version = "0.1.63"
@@ -95,6 +156,16 @@ dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "indexmap"
+version = "2.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cea70ddb795996207ad57735b50c5982d8844f38ba9ee5f1aedcfb708a2aa11e"
+dependencies = [
+ "equivalent",
+ "hashbrown",
+]
+
 [[package]]
 name = "js-sys"
 version = "0.3.77"
@@ -140,14 +211,36 @@ checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"
 
 [[package]]
 name = "parse_datetime"
-version = "0.10.0"
+version = "0.11.0"
 dependencies = [
  "chrono",
  "num-traits",
  "regex",
+ "rstest",
  "winnow",
 ]
 
+[[package]]
+name = "pin-project-lite"
+version = "0.2.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3b3cff922bd51709b605d9ead9aa71031d81447142d828eb4a6eba76fe619f9b"
+
+[[package]]
+name = "pin-utils"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
+
+[[package]]
+name = "proc-macro-crate"
+version = "3.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "edce586971a4dfaa28950c6f18ed55e0406c1ab88bbce2c6f6293a7aaba73d35"
+dependencies = [
+ "toml_edit",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.95"
@@ -195,18 +288,74 @@ version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"
 
+[[package]]
+name = "relative-path"
+version = "1.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba39f3699c378cd8970968dcbff9c43159ea4cfbd88d43c00b22f2ef10a435d2"
+
+[[package]]
+name = "rstest"
+version = "0.26.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f5a3193c063baaa2a95a33f03035c8a72b83d97a54916055ba22d35ed3839d49"
+dependencies = [
+ "futures-timer",
+ "futures-util",
+ "rstest_macros",
+]
+
+[[package]]
+name = "rstest_macros"
+version = "0.26.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c845311f0ff7951c5506121a9ad75aec44d083c31583b2ea5a30bcb0b0abba0"
+dependencies = [
+ "cfg-if",
+ "glob",
+ "proc-macro-crate",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "relative-path",
+ "rustc_version",
+ "syn",
+ "unicode-ident",
+]
+
+[[package]]
+name = "rustc_version"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfcb3a22ef46e85b45de6ee7e79d063319ebb6594faafcf1c225ea92ab6e9b92"
+dependencies = [
+ "semver",
+]
+
 [[package]]
 name = "rustversion"
 version = "1.0.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "eded382c5f5f786b989652c49544c4877d9f015cc22e145a5ea8ea66c2921cd2"
 
+[[package]]
+name = "semver"
+version = "1.0.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56e6fa9c48d24d85fb3de5ad847117517440f6beceb7798af16b4a87d616b8d0"
+
 [[package]]
 name = "shlex"
 version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
+[[package]]
+name = "slab"
+version = "0.4.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "04dc19736151f35336d325007ac991178d504a119863a2fcb3758cdb5e52c50d"
+
 [[package]]
 name = "syn"
 version = "2.0.101"
@@ -218,6 +367,23 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "toml_datetime"
+version = "0.6.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22cddaf88f4fbc13c51aebbf5f8eceb5c7c5a9da2ac40a13519eb5b0a0e8f11c"
+
+[[package]]
+name = "toml_edit"
+version = "0.22.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41fe8c660ae4257887cf66394862d21dbca4a6ddd26f04a3560410406a2f819a"
+dependencies = [
+ "indexmap",
+ "toml_datetime",
+ "winnow",
+]
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.18"
@@ -343,9 +509,9 @@ dependencies = [
 
 [[package]]
 name = "winnow"
-version = "0.7.10"
+version = "0.7.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c06928c8748d81b05c9be96aad92e1b6ff01833332f281e8cfca3be4b35fc9ec"
+checksum = "f3edebf492c8125044983378ecb5766203ad3b4c2f7a922bd7dd207f6d443e95"
 dependencies = [
  "memchr",
 ]

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "parse_datetime"
 description = "parsing human-readable time strings and converting them to a DateTime"
-version = "0.10.0"
+version = "0.11.0"
 edition = "2021"
 license = "MIT"
 repository = "https://github.com/uutils/parse_datetime"
@@ -13,3 +13,6 @@ regex = "1.10.4"
 chrono = { version="0.4.38", default-features=false, features=["std", "alloc", "clock"] }
 winnow = "0.7.10"
 num-traits = "0.2.19"
+
+[dev-dependencies]
+rstest = "0.26"

README.md

@@ -10,7 +10,7 @@ A Rust crate for parsing human-readable relative time strings and human-readable
 
 - Parses a variety of human-readable and standard time formats.
 - Supports positive and negative durations.
-- Allows for chaining time units (e.g., "1 hour 2 minutes" or "2 days and 2 hours").
+- Allows for chaining time units (e.g., "1 hour 2 minutes" or "2 days 2 hours ago").
 - Calculate durations relative to a specified date.
 - Relies on Chrono
 
@@ -58,7 +58,6 @@ The `parse_datetime` and `parse_datetime_at_date` functions support absolute dat
 - "tomorrow"
 - use "ago" for the past
 - use "next" or "last" with `unit` (e.g., "next week", "last year")
-- combined units with "and" or "," (e.g., "2 years and 1 month", "1 day, 2 hours" or "2 weeks 1 second")
 - unix timestamps (for example "@0" "@1344000")
 
 `num` can be a positive or negative integer.

fuzz/Cargo.lock

@@ -138,9 +138,9 @@ checksum = "6a987beff54b60ffa6d51982e1aa1146bc42f19bd26be28b0586f252fccf5317"
 
 [[package]]
 name = "libfuzzer-sys"
-version = "0.4.9"
+version = "0.4.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cf78f52d400cf2d84a3a973a78a592b4adc535739e0a5597a0da6f0c357adc75"
+checksum = "5037190e1f70cbeef565bd267599242926f724d3b8a9f510fd7e0b540cfa4404"
 dependencies = [
  "arbitrary",
  "cc",

src/items/builder.rs

@@ -0,0 +1,320 @@
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use chrono::{DateTime, Datelike, FixedOffset, NaiveDate, TimeZone, Timelike};
+
+use super::{date, relative, time, weekday};
+
+/// The builder is used to construct a DateTime object from various components.
+/// The parser creates a `DateTimeBuilder` object with the parsed components,
+/// but without the baseline date and time. So you normally need to set the base
+/// date and time using the `set_base()` method before calling `build()`, or
+/// leave it unset to use the current date and time as the base.
+#[derive(Debug, Default)]
+pub struct DateTimeBuilder {
+    base: Option<DateTime<FixedOffset>>,
+    timestamp: Option<f64>,
+    date: Option<date::Date>,
+    time: Option<time::Time>,
+    weekday: Option<weekday::Weekday>,
+    timezone: Option<time::Offset>,
+    relative: Vec<relative::Relative>,
+}
+
+impl DateTimeBuilder {
+    pub(super) fn new() -> Self {
+        Self::default()
+    }
+
+    /// Sets the base date and time for the builder. If not set, the current
+    /// date and time will be used.
+    pub(super) fn set_base(mut self, base: DateTime<FixedOffset>) -> Self {
+        self.base = Some(base);
+        self
+    }
+
+    /// Timestamp value is exclusive to other date/time components. Caller of
+    /// the builder must ensure that it is not combined with other items.
+    pub(super) fn set_timestamp(mut self, ts: f64) -> Result<Self, &'static str> {
+        self.timestamp = Some(ts);
+        Ok(self)
+    }
+
+    pub(super) fn set_year(mut self, year: u32) -> Result<Self, &'static str> {
+        if let Some(date) = self.date.as_mut() {
+            if date.year.is_some() {
+                Err("year cannot appear more than once")
+            } else {
+                date.year = Some(year);
+                Ok(self)
+            }
+        } else {
+            self.date = Some(date::Date {
+                day: 1,
+                month: 1,
+                year: Some(year),
+            });
+            Ok(self)
+        }
+    }
+
+    pub(super) fn set_date(mut self, date: date::Date) -> Result<Self, &'static str> {
+        if self.date.is_some() || self.timestamp.is_some() {
+            Err("date cannot appear more than once")
+        } else {
+            self.date = Some(date);
+            Ok(self)
+        }
+    }
+
+    pub(super) fn set_time(mut self, time: time::Time) -> Result<Self, &'static str> {
+        if self.time.is_some() || self.timestamp.is_some() {
+            Err("time cannot appear more than once")
+        } else if self.timezone.is_some() && time.offset.is_some() {
+            Err("time offset and timezone are mutually exclusive")
+        } else {
+            self.time = Some(time);
+            Ok(self)
+        }
+    }
+
+    pub(super) fn set_weekday(mut self, weekday: weekday::Weekday) -> Result<Self, &'static str> {
+        if self.weekday.is_some() {
+            Err("weekday cannot appear more than once")
+        } else {
+            self.weekday = Some(weekday);
+            Ok(self)
+        }
+    }
+
+    pub(super) fn set_timezone(mut self, timezone: time::Offset) -> Result<Self, &'static str> {
+        if self.timezone.is_some() {
+            Err("timezone cannot appear more than once")
+        } else if self.time.as_ref().and_then(|t| t.offset.as_ref()).is_some() {
+            Err("time offset and timezone are mutually exclusive")
+        } else {
+            self.timezone = Some(timezone);
+            Ok(self)
+        }
+    }
+
+    pub(super) fn push_relative(mut self, relative: relative::Relative) -> Self {
+        self.relative.push(relative);
+        self
+    }
+
+    pub(super) fn build(self) -> Option<DateTime<FixedOffset>> {
+        let base = self.base.unwrap_or_else(|| chrono::Local::now().into());
+
+        // If any of the following items are set, we truncate the time portion
+        // of the base date to zero; otherwise, we use the base date as is.
+        let mut dt = if self.timestamp.is_none()
+            && self.date.is_none()
+            && self.time.is_none()
+            && self.weekday.is_none()
+            && self.timezone.is_none()
+        {
+            base
+        } else {
+            new_date(
+                base.year(),
+                base.month(),
+                base.day(),
+                0,
+                0,
+                0,
+                0,
+                *base.offset(),
+            )?
+        };
+
+        if let Some(ts) = self.timestamp {
+            // TODO: How to make the fract -> nanosecond conversion more precise?
+            // Maybe considering using the
+            // [rust_decimal](https://crates.io/crates/rust_decimal) crate?
+            match chrono::Utc.timestamp_opt(ts as i64, (ts.fract() * 10f64.powi(9)).round() as u32)
+            {
+                chrono::MappedLocalTime::Single(t) => {
+                    // If the timestamp is valid, we can use it directly.
+                    dt = t.with_timezone(&dt.timezone());
+                }
+                chrono::MappedLocalTime::Ambiguous(earliest, _latest) => {
+                    // TODO: When there is a fold in the local time, which value
+                    // do we choose? For now, we use the earliest one.
+                    dt = earliest.with_timezone(&dt.timezone());
+                }
+                chrono::MappedLocalTime::None => {
+                    return None; // Invalid timestamp
+                }
+            }
+        }
+
+        if let Some(date::Date { year, month, day }) = self.date {
+            dt = new_date(
+                year.map(|x| x as i32).unwrap_or(dt.year()),
+                month,
+                day,
+                dt.hour(),
+                dt.minute(),
+                dt.second(),
+                dt.nanosecond(),
+                *dt.offset(),
+            )?;
+        }
+
+        if let Some(time::Time {
+            hour,
+            minute,
+            second,
+            ref offset,
+        }) = self.time
+        {
+            let offset = offset
+                .clone()
+                .and_then(|o| chrono::FixedOffset::try_from(o).ok())
+                .unwrap_or(*dt.offset());
+
+            dt = new_date(
+                dt.year(),
+                dt.month(),
+                dt.day(),
+                hour,
+                minute,
+                second as u32,
+                (second.fract() * 10f64.powi(9)).round() as u32,
+                offset,
+            )?;
+        }
+
+        if let Some(weekday::Weekday { offset, day }) = self.weekday {
+            if self.time.is_none() {
+                dt = new_date(dt.year(), dt.month(), dt.day(), 0, 0, 0, 0, *dt.offset())?;
+            }
+
+            let mut offset = offset;
+            let day = day.into();
+
+            // If the current day is not the target day, we need to adjust
+            // the x value to ensure we find the correct day.
+            //
+            // Consider this:
+            // Assuming today is Monday, next Friday is actually THIS Friday;
+            // but next Monday is indeed NEXT Monday.
+            if dt.weekday() != day && offset > 0 {
+                offset -= 1;
+            }
+
+            // Calculate the delta to the target day.
+            //
+            // Assuming today is Thursday, here are some examples:
+            //
+            // Example 1: last Thursday (x = -1, day = Thursday)
+            //            delta = (3 - 3) % 7 + (-1) * 7 = -7
+            //
+            // Example 2: last Monday (x = -1, day = Monday)
+            //            delta = (0 - 3) % 7 + (-1) * 7 = -3
+            //
+            // Example 3: next Monday (x = 1, day = Monday)
+            //            delta = (0 - 3) % 7 + (0) * 7 = 4
+            // (Note that we have adjusted the x value above)
+            //
+            // Example 4: next Thursday (x = 1, day = Thursday)
+            //            delta = (3 - 3) % 7 + (1) * 7 = 7
+            let delta = (day.num_days_from_monday() as i32
+                - dt.weekday().num_days_from_monday() as i32)
+                .rem_euclid(7)
+                + offset.checked_mul(7)?;
+
+            dt = if delta < 0 {
+                dt.checked_sub_days(chrono::Days::new((-delta) as u64))?
+            } else {
+                dt.checked_add_days(chrono::Days::new(delta as u64))?
+            }
+        }
+
+        for rel in self.relative {
+            // TODO: Handle potential overflows in the addition operations.
+            match rel {
+                relative::Relative::Years(x) => {
+                    dt = dt.with_year(dt.year() + x)?;
+                }
+                relative::Relative::Months(x) => {
+                    // *NOTE* This is done in this way to conform to
+                    // GNU behavior.
+                    let days = last_day_of_month(dt.year(), dt.month());
+                    if x >= 0 {
+                        dt += dt
+                            .date_naive()
+                            .checked_add_days(chrono::Days::new((days * x as u32) as u64))?
+                            .signed_duration_since(dt.date_naive());
+                    } else {
+                        dt += dt
+                            .date_naive()
+                            .checked_sub_days(chrono::Days::new((days * -x as u32) as u64))?
+                            .signed_duration_since(dt.date_naive());
+                    }
+                }
+                relative::Relative::Days(x) => dt += chrono::Duration::days(x.into()),
+                relative::Relative::Hours(x) => dt += chrono::Duration::hours(x.into()),
+                relative::Relative::Minutes(x) => {
+                    dt += chrono::Duration::try_minutes(x.into())?;
+                }
+                // Seconds are special because they can be given as a float.
+                relative::Relative::Seconds(x) => {
+                    dt += chrono::Duration::try_seconds(x as i64)?;
+                }
+            }
+        }
+
+        if let Some(offset) = self.timezone {
+            dt = with_timezone_restore(offset, dt)?;
+        }
+
+        Some(dt)
+    }
+}
+
+#[allow(clippy::too_many_arguments)]
+fn new_date(
+    year: i32,
+    month: u32,
+    day: u32,
+    hour: u32,
+    minute: u32,
+    second: u32,
+    nano: u32,
+    offset: FixedOffset,
+) -> Option<DateTime<FixedOffset>> {
+    let newdate = NaiveDate::from_ymd_opt(year, month, day)
+        .and_then(|naive| naive.and_hms_nano_opt(hour, minute, second, nano))?;
+
+    Some(DateTime::<FixedOffset>::from_local(newdate, offset))
+}
+
+/// Restores year, month, day, etc after applying the timezone
+/// returns None if timezone overflows the date
+fn with_timezone_restore(
+    offset: time::Offset,
+    at: DateTime<FixedOffset>,
+) -> Option<DateTime<FixedOffset>> {
+    let offset: FixedOffset = chrono::FixedOffset::try_from(offset).ok()?;
+    let copy = at;
+    let x = at
+        .with_timezone(&offset)
+        .with_day(copy.day())?
+        .with_month(copy.month())?
+        .with_year(copy.year())?
+        .with_hour(copy.hour())?
+        .with_minute(copy.minute())?
+        .with_second(copy.second())?
+        .with_nanosecond(copy.nanosecond())?;
+    Some(x)
+}
+
+fn last_day_of_month(year: i32, month: u32) -> u32 {
+    NaiveDate::from_ymd_opt(year, month + 1, 1)
+        .unwrap_or(NaiveDate::from_ymd_opt(year + 1, 1, 1).unwrap())
+        .pred_opt()
+        .unwrap()
+        .day()
+}

src/items/combined.rs

@@ -12,7 +12,8 @@
 //! > In this format, the time of day should use 24-hour notation. Fractional
 //! > seconds are allowed, with either comma or period preceding the fraction.
 //! > ISO 8601 fractional minutes and hours are not supported. Typically, hosts
-//! > support nanosecond timestamp resolution; excess precision is silently discarded.
+//! > support nanosecond timestamp resolution; excess precision is silently
+//! > discarded.
 use winnow::{
     combinator::{alt, trace},
     seq, ModalResult, Parser,
@@ -22,22 +23,22 @@ use crate::items::space;
 
 use super::{
     date::{self, Date},
-    s,
+    primitive::s,
     time::{self, Time},
 };
 
 #[derive(PartialEq, Debug, Clone, Default)]
-pub struct DateTime {
+pub(crate) struct DateTime {
     pub(crate) date: Date,
     pub(crate) time: Time,
 }
 
-pub fn parse(input: &mut &str) -> ModalResult<DateTime> {
+pub(crate) fn parse(input: &mut &str) -> ModalResult<DateTime> {
     seq!(DateTime {
-        date: trace("date iso", alt((date::iso1, date::iso2))),
+        date: trace("iso_date", alt((date::iso1, date::iso2))),
         // Note: the `T` is lowercased by the main parse function
         _: alt((s('t').void(), (' ', space).void())),
-        time: trace("time iso", time::iso),
+        time: trace("iso_time", time::iso),
     })
     .parse_next(input)
 }

src/items/epoch.rs

@@ -0,0 +1,35 @@
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use winnow::{combinator::preceded, ModalResult, Parser};
+
+use super::primitive::{float, s};
+
+/// Parse a timestamp in the form of `@1234567890`.
+pub fn parse(input: &mut &str) -> ModalResult<f64> {
+    s(preceded("@", float)).parse_next(input)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::parse;
+
+    fn float_eq(a: f64, b: f64) -> bool {
+        (a - b).abs() < f64::EPSILON
+    }
+
+    #[test]
+    fn float() {
+        let mut input = "@1234567890";
+        assert!(float_eq(parse(&mut input).unwrap(), 1234567890.0));
+
+        let mut input = "@1234567890.12345";
+        assert!(float_eq(parse(&mut input).unwrap(), 1234567890.12345));
+
+        let mut input = "@1234567890,12345";
+        assert!(float_eq(parse(&mut input).unwrap(), 1234567890.12345));
+
+        let mut input = "@-1234567890.12345";
+        assert_eq!(parse(&mut input).unwrap(), -1234567890.12345);
+    }
+}

src/items/ordinal.rs

@@ -1,14 +1,15 @@
 // For the full copyright and license information, please view the LICENSE
 // file that was distributed with this source code.
 
-use super::s;
 use winnow::{
-    ascii::{alpha1, dec_uint},
+    ascii::alpha1,
     combinator::{alt, opt},
     ModalResult, Parser,
 };
 
-pub fn ordinal(input: &mut &str) -> ModalResult<i32> {
+use super::primitive::{dec_uint, s};
+
+pub(super) fn ordinal(input: &mut &str) -> ModalResult<i32> {
     alt((text_ordinal, number_ordinal)).parse_next(input)
 }
 

src/items/primitive.rs

@@ -0,0 +1,140 @@
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+//! Primitive combinators.
+
+use winnow::{
+    ascii::{digit1, multispace0},
+    combinator::{alt, delimited, not, opt, peek, preceded, repeat, separated},
+    error::{ContextError, ParserError, StrContext, StrContextValue},
+    stream::AsChar,
+    token::{none_of, one_of, take_while},
+    Parser,
+};
+
+/// Allow spaces and comments before a parser
+///
+/// Every token parser should be wrapped in this to allow spaces and comments.
+/// It is only preceding, because that allows us to check mandatory whitespace
+/// after running the parser.
+pub(super) fn s<'a, O, E>(p: impl Parser<&'a str, O, E>) -> impl Parser<&'a str, O, E>
+where
+    E: ParserError<&'a str>,
+{
+    preceded(space, p)
+}
+
+/// Parse the space in-between tokens
+///
+/// You probably want to use the [`s`] combinator instead.
+pub(super) fn space<'a, E>(input: &mut &'a str) -> winnow::Result<(), E>
+where
+    E: ParserError<&'a str>,
+{
+    separated(0.., multispace0, alt((comment, ignored_hyphen_or_plus))).parse_next(input)
+}
+
+/// A hyphen or plus is ignored when it is not followed by a digit
+///
+/// This includes being followed by a comment! Compare these inputs:
+/// ```txt
+/// - 12 weeks
+/// - (comment) 12 weeks
+/// ```
+/// The last comment should be ignored.
+///
+/// The plus is undocumented, but it seems to be ignored.
+fn ignored_hyphen_or_plus<'a, E>(input: &mut &'a str) -> winnow::Result<(), E>
+where
+    E: ParserError<&'a str>,
+{
+    (
+        alt(('-', '+')),
+        multispace0,
+        peek(not(take_while(1, AsChar::is_dec_digit))),
+    )
+        .void()
+        .parse_next(input)
+}
+
+/// Parse a comment
+///
+/// A comment is given between parentheses, which must be balanced. Any other
+/// tokens can be within the comment.
+fn comment<'a, E>(input: &mut &'a str) -> winnow::Result<(), E>
+where
+    E: ParserError<&'a str>,
+{
+    delimited(
+        '(',
+        repeat(0.., alt((none_of(['(', ')']).void(), comment))),
+        ')',
+    )
+    .parse_next(input)
+}
+
+/// Parse a signed decimal integer.
+///
+/// Rationale for not using `winnow::ascii::dec_int`: When upgrading winnow from
+/// 0.5 to 0.7, we discovered that `winnow::ascii::dec_int` now accepts only the
+/// following two forms:
+///
+/// - 0
+/// - [+-]?[1-9][0-9]*
+///
+/// Inputs like [+-]?0[0-9]* (e.g., `+012`) are therefore rejected. We provide a
+/// custom implementation to support such zero-prefixed integers.
+#[allow(unused)]
+pub(super) fn dec_int<'a, E>(input: &mut &'a str) -> winnow::Result<i32, E>
+where
+    E: ParserError<&'a str>,
+{
+    (opt(one_of(['+', '-'])), digit1)
+        .void()
+        .take()
+        .verify_map(|s: &str| s.parse().ok())
+        .parse_next(input)
+}
+
+/// Parse an unsigned decimal integer.
+///
+/// See the rationale for `dec_int` for why we don't use
+/// `winnow::ascii::dec_uint`.
+pub(super) fn dec_uint<'a, E>(input: &mut &'a str) -> winnow::Result<u32, E>
+where
+    E: ParserError<&'a str>,
+{
+    digit1
+        .void()
+        .take()
+        .verify_map(|s: &str| s.parse().ok())
+        .parse_next(input)
+}
+
+/// Parse a float number.
+///
+/// Rationale for not using `winnow::ascii::float`: the `float` parser provided
+/// by winnow accepts E-notation numbers (e.g., `1.23e4`), whereas GNU date
+/// rejects such numbers. To remain compatible with GNU date, we provide a
+/// custom implementation that only accepts inputs like [+-]?[0-9]+(\.[0-9]+)?.
+pub(super) fn float<'a, E>(input: &mut &'a str) -> winnow::Result<f64, E>
+where
+    E: ParserError<&'a str>,
+{
+    (
+        opt(one_of(['+', '-'])),
+        digit1,
+        opt(preceded(one_of(['.', ',']), digit1)),
+    )
+        .void()
+        .take()
+        .verify_map(|s: &str| s.replace(",", ".").parse().ok())
+        .parse_next(input)
+}
+
+/// Create a context error with a reason.
+pub(super) fn ctx_err(reason: &'static str) -> ContextError {
+    let mut err = ContextError::new();
+    err.push(StrContext::Expected(StrContextValue::Description(reason)));
+    err
+}

src/items/relative.rs

@@ -32,12 +32,15 @@
 //! > ‘this thursday’.
 
 use winnow::{
-    ascii::{alpha1, float},
+    ascii::alpha1,
     combinator::{alt, opt},
     ModalResult, Parser,
 };
 
-use super::{ordinal::ordinal, s};
+use super::{
+    ordinal::ordinal,
+    primitive::{float, s},
+};
 
 #[derive(Clone, Copy, Debug, PartialEq)]
 pub enum Relative {
@@ -51,13 +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),
         }
     }

src/items/time.rs

@@ -41,9 +41,8 @@ use std::fmt::Display;
 
 use chrono::FixedOffset;
 use winnow::{
-    ascii::{digit1, float},
     combinator::{alt, opt, peek, preceded},
-    error::{ContextError, ErrMode, StrContext, StrContextValue},
+    error::{ContextError, ErrMode},
     seq,
     stream::AsChar,
     token::take_while,
@@ -52,7 +51,10 @@ use winnow::{
 
 use crate::ParseDateTimeError;
 
-use super::{dec_uint, relative, s};
+use super::{
+    primitive::{ctx_err, dec_uint, float, s},
+    relative,
+};
 
 #[derive(PartialEq, Debug, Clone, Default)]
 pub struct Offset {
@@ -70,7 +72,7 @@ pub struct Time {
 }
 
 impl Offset {
-    fn merge(self, offset: Offset) -> Option<Offset> {
+    fn merge(self, offset: Offset) -> Offset {
         fn combine(a: u32, neg_a: bool, b: u32, neg_b: bool) -> (u32, bool) {
             if neg_a == neg_b {
                 (a + b, neg_a)
@@ -89,11 +91,11 @@ impl Offset {
         let hours = hours_minutes / 60;
         let minutes = hours_minutes % 60;
 
-        Some(Offset {
+        Offset {
             negative,
             hours,
             minutes,
-        })
+        }
     }
 }
 
@@ -140,7 +142,7 @@ impl Display for Offset {
 }
 
 #[derive(Clone)]
-enum Suffix {
+enum Meridiem {
     Am,
     Pm,
 }
@@ -154,7 +156,7 @@ pub fn parse(input: &mut &str) -> ModalResult<Time> {
 /// Also used by the [`combined`](super::combined) module
 pub fn iso(input: &mut &str) -> ModalResult<Time> {
     alt((
-        (hour24, timezone).map(|(hour, offset)| Time {
+        (hour24, timezone_num).map(|(hour, offset)| Time {
             hour,
             minute: 0,
             second: 0.0,
@@ -165,7 +167,7 @@ pub fn iso(input: &mut &str) -> ModalResult<Time> {
             _: colon,
             minute: minute,
             second: opt(preceded(colon, second)).map(|s| s.unwrap_or(0.0)),
-            offset: opt(timezone)
+            offset: opt(timezone_num)
         }),
     ))
     .parse_next(input)
@@ -175,30 +177,35 @@ pub fn iso(input: &mut &str) -> ModalResult<Time> {
 ///
 /// The hours are restricted to 12 or lower in this format
 fn am_pm_time(input: &mut &str) -> ModalResult<Time> {
-    seq!(
+    let (h, m, s, meridiem) = (
         hour12,
         opt(preceded(colon, minute)),
         opt(preceded(colon, second)),
         alt((
-            s("am").value(Suffix::Am),
-            s("a.m.").value(Suffix::Am),
-            s("pm").value(Suffix::Pm),
-            s("p.m.").value(Suffix::Pm)
+            s("am").value(Meridiem::Am),
+            s("a.m.").value(Meridiem::Am),
+            s("pm").value(Meridiem::Pm),
+            s("p.m.").value(Meridiem::Pm),
         )),
     )
-    .map(|(h, m, s, suffix)| {
-        let mut h = h % 12;
-        if let Suffix::Pm = suffix {
-            h += 12;
-        }
-        Time {
-            hour: h,
-            minute: m.unwrap_or(0),
-            second: s.unwrap_or(0.0),
-            offset: None,
-        }
+        .parse_next(input)?;
+
+    if h == 0 {
+        return Err(ErrMode::Cut(ctx_err(
+            "hour must be greater than 0 when meridiem is specified",
+        )));
+    }
+
+    let mut h = h % 12;
+    if let Meridiem::Pm = meridiem {
+        h += 12;
+    }
+    Ok(Time {
+        hour: h,
+        minute: m.unwrap_or(0),
+        second: s.unwrap_or(0.0),
+        offset: None,
     })
-    .parse_next(input)
 }
 
 /// Parse a colon preceded by whitespace
@@ -223,11 +230,18 @@ fn minute(input: &mut &str) -> ModalResult<u32> {
 
 /// Parse a number of seconds (preceded by whitespace)
 fn second(input: &mut &str) -> ModalResult<f64> {
-    s(float).verify(|x| *x < 60.0).parse_next(input)
+    s(float)
+        .verify(|x| *x < 60.0)
+        .map(|x| {
+            // Truncates the fractional part of seconds to 9 digits.
+            let factor = 10f64.powi(9);
+            (x * factor).trunc() / factor
+        })
+        .parse_next(input)
 }
 
 pub(crate) fn timezone(input: &mut &str) -> ModalResult<Offset> {
-    alt((timezone_num, timezone_name_offset)).parse_next(input)
+    timezone_name_offset.parse_next(input)
 }
 
 /// Parse a timezone starting with `+` or `-`
@@ -245,19 +259,11 @@ fn timezone_num(input: &mut &str) -> ModalResult<Offset> {
         .parse_next(input)
         .and_then(|(negative, (hours, minutes))| {
             if !(0..=12).contains(&hours) {
-                let mut ctx_err = ContextError::new();
-                ctx_err.push(StrContext::Expected(StrContextValue::Description(
-                    "timezone hour between 0 and 12",
-                )));
-                return Err(ErrMode::Cut(ctx_err));
+                return Err(ErrMode::Cut(ctx_err("timezone hour between 0 and 12")));
             }
 
             if !(0..=60).contains(&minutes) {
-                let mut ctx_err = ContextError::new();
-                ctx_err.push(StrContext::Expected(StrContextValue::Description(
-                    "timezone minute between 0 and 60",
-                )));
-                return Err(ErrMode::Cut(ctx_err));
+                return Err(ErrMode::Cut(ctx_err("timezone minute between 0 and 60")));
             }
 
             Ok(Offset {
@@ -271,14 +277,7 @@ fn timezone_num(input: &mut &str) -> ModalResult<Offset> {
 /// Parse a timezone offset with a colon separating hours and minutes
 fn timezone_colon(input: &mut &str) -> ModalResult<(u32, u32)> {
     seq!(
-        s(take_while(1..=2, AsChar::is_dec_digit)).try_map(|x: &str| {
-            // parse will fail on empty input
-            if x.is_empty() {
-                Ok(0)
-            } else {
-                x.parse()
-            }
-        }),
+        s(take_while(1..=2, AsChar::is_dec_digit)).try_map(|x: &str| x.parse()),
         _: colon,
         s(take_while(1..=2, AsChar::is_dec_digit)).try_map(|x: &str| x.parse()),
     )
@@ -287,26 +286,21 @@ fn timezone_colon(input: &mut &str) -> ModalResult<(u32, u32)> {
 
 /// Parse a timezone offset without colon
 fn timezone_colonless(input: &mut &str) -> ModalResult<(u32, u32)> {
-    if let Ok(x) = peek(s(digit1::<&str, ContextError>)).parse_next(input) {
-        if x.len() > 4 {
-            let mut ctx_err = ContextError::new();
-            ctx_err.push(StrContext::Expected(StrContextValue::Description(
-                "timezone offset cannot be more than 4 digits",
-            )));
-            return Err(ErrMode::Cut(ctx_err));
-        }
-    }
-
-    // TODO: GNU date supports number strings with leading zeroes, e.g.,
-    // `UTC+000001100` is valid.
-    s(take_while(0..=4, AsChar::is_dec_digit))
-        .verify_map(|x: &str| {
-            Some(match x.len() {
+    s(take_while(0.., AsChar::is_dec_digit))
+        .verify_map(|s: &str| {
+            // GNU date supports number strings with leading zeroes, e.g.,
+            // `UTC+000001100` is valid.
+            let s = if s.len() > 4 {
+                s.trim_start_matches('0')
+            } else {
+                s
+            };
+            Some(match s.len() {
                 0 => (0, 0),
-                1 | 2 => (x.parse().ok()?, 0),
+                1 | 2 => (s.parse().ok()?, 0),
                 // The minutes are the last two characters here, for some reason.
-                3 => (x[..1].parse().ok()?, x[1..].parse().ok()?),
-                4 => (x[..2].parse().ok()?, x[2..].parse().ok()?),
+                3 => (s[..1].parse().ok()?, s[1..].parse().ok()?),
+                4 => (s[..2].parse().ok()?, s[2..].parse().ok()?),
                 _ => return None,
             })
         })
@@ -328,9 +322,7 @@ fn timezone_name_offset(input: &mut &str) -> ModalResult<Offset> {
     // Only process if the input cannot be parsed as a relative time.
     if peek(relative::parse).parse_next(input).is_err() {
         if let Ok(other_tz) = timezone_num.parse_next(input) {
-            let newtz = tz
-                .merge(other_tz)
-                .ok_or(ErrMode::Cut(ContextError::new()))?;
+            let newtz = tz.merge(other_tz);
 
             return Ok(newtz);
         };
@@ -623,6 +615,12 @@ mod tests {
         }
     }
 
+    #[test]
+    fn invalid() {
+        assert!(parse(&mut "00:00am").is_err());
+        assert!(parse(&mut "00:00:00am").is_err());
+    }
+
     #[test]
     fn hours_only() {
         let reference = Time {
@@ -829,6 +827,8 @@ mod tests {
 
         assert_eq!("(0, 0)", aux(&mut "0000"));
         assert_eq!("(12, 34)", aux(&mut "1234"));
+        assert_eq!("(12, 34)", aux(&mut "00001234"));
+        assert!(timezone_colonless(&mut "12345").is_err());
     }
 
     #[test]
@@ -837,17 +837,29 @@ mod tests {
         let make_timezone = |input: &mut &str| {
             timezone(input)
                 .map_err(|e| eprintln!("TEST FAILED AT:\n{e}"))
-                .map(|offset| format!("{}", offset))
+                .map(|offset| format!("{offset}"))
                 .expect("expect tests to succeed")
         };
 
-        assert_eq!("+00:00", make_timezone(&mut "+00:00"));
-        assert_eq!("+00:00", make_timezone(&mut "+0000"));
-        assert_eq!("-00:00", make_timezone(&mut "-0000"));
         assert_eq!("+00:00", make_timezone(&mut "gmt"));
         assert_eq!("+01:00", make_timezone(&mut "a"));
         assert_eq!("+00:00", make_timezone(&mut "utc"));
         assert_eq!("-02:00", make_timezone(&mut "brst"));
         assert_eq!("-03:00", make_timezone(&mut "brt"));
     }
+
+    #[test]
+    fn test_timezone_num() {
+        use super::timezone_num;
+        let make_timezone = |input: &mut &str| {
+            timezone_num(input)
+                .map_err(|e| eprintln!("TEST FAILED AT:\n{e}"))
+                .map(|offset| format!("{offset}"))
+                .expect("expect tests to succeed")
+        };
+
+        assert_eq!("+00:00", make_timezone(&mut "+00:00"));
+        assert_eq!("+00:00", make_timezone(&mut "+0000"));
+        assert_eq!("-00:00", make_timezone(&mut "-0000"));
+    }
 }

src/items/timezone.rs

@@ -0,0 +1,10 @@
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use winnow::ModalResult;
+
+use super::time;
+
+pub(crate) fn parse(input: &mut &str) -> ModalResult<time::Offset> {
+    time::timezone(input)
+}

src/items/weekday.rs

@@ -21,11 +21,15 @@
 //! >
 //! > A comma following a day of the week item is ignored.
 
-use winnow::{ascii::alpha1, combinator::opt, seq, ModalResult, Parser};
+use winnow::{
+    ascii::alpha1,
+    combinator::{opt, terminated},
+    seq, ModalResult, Parser,
+};
 
-use super::{ordinal::ordinal, s};
+use super::{ordinal::ordinal, primitive::s};
 
-#[derive(PartialEq, Eq, Debug)]
+#[derive(PartialEq, Eq, Debug, Copy, Clone)]
 pub(crate) enum Day {
     Monday,
     Tuesday,
@@ -55,10 +59,12 @@ impl From<Day> for chrono::Weekday {
         }
     }
 }
-pub fn parse(input: &mut &str) -> ModalResult<Weekday> {
+
+/// Parse a weekday item.
+pub(super) fn parse(input: &mut &str) -> ModalResult<Weekday> {
     seq!(Weekday {
         offset: opt(ordinal).map(|o| o.unwrap_or_default()),
-        day: day,
+        day: terminated(day, opt(s(","))),
     })
     .parse_next(input)
 }
@@ -134,4 +140,17 @@ mod tests {
             );
         }
     }
+
+    #[test]
+    fn optional_comma() {
+        for mut s in ["monday,", "mon,", "mon.,", "mon. ,"] {
+            assert_eq!(
+                parse(&mut s).unwrap(),
+                Weekday {
+                    offset: 0,
+                    day: Day::Monday,
+                }
+            );
+        }
+    }
 }

src/items/year.rs

@@ -0,0 +1,78 @@
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+//! Parse a year from a string.
+//!
+//! The year must be parsed to a string first, this is to handle a specific GNU
+//! compatibility quirk. According to the GNU documentation: "if the year is 68
+//! or smaller, then 2000 is added to it; otherwise, if year is less than 100,
+//! then 1900 is added to it." This adjustment only applies to two-digit year
+//! strings. For example, `"00"` is interpreted as `2000`, whereas `"0"`,
+//! `"000"`, or `"0000"` are interpreted as `0`.
+
+use winnow::{error::ErrMode, stream::AsChar, token::take_while, ModalResult, Parser};
+
+use super::primitive::{ctx_err, s};
+
+pub(super) fn parse(input: &mut &str) -> ModalResult<u32> {
+    year_from_str(year_str(input)?).map_err(|e| ErrMode::Cut(ctx_err(e)))
+}
+
+// TODO: Leverage `TryFrom` trait.
+pub(super) fn year_from_str(year_str: &str) -> Result<u32, &'static str> {
+    let mut year = year_str
+        .parse::<u32>()
+        .map_err(|_| "year must be a valid number")?;
+
+    // If year is 68 or smaller, then 2000 is added to it; otherwise, if year
+    // is less than 100, then 1900 is added to it.
+    //
+    // GNU quirk: this only applies to two-digit years. For example,
+    // "98-01-01" will be parsed as "1998-01-01", whereas "098-01-01" will be
+    // parsed as "0098-01-01".
+    if year_str.len() == 2 {
+        if year <= 68 {
+            year += 2000
+        } else {
+            year += 1900
+        }
+    }
+
+    // 2147485547 is the maximum value accepted by GNU, but chrono only
+    // behaves like GNU for years in the range: [0, 9999], so we keep in the
+    // range [0, 9999].
+    //
+    // See discussion in https://github.com/uutils/parse_datetime/issues/160.
+    if year > 9999 {
+        return Err("year must be no greater than 9999");
+    }
+
+    Ok(year)
+}
+
+pub(super) fn year_str<'a>(input: &mut &'a str) -> ModalResult<&'a str> {
+    s(take_while(1.., AsChar::is_dec_digit)).parse_next(input)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::parse;
+
+    #[test]
+    fn test_year() {
+        // 2-characters are converted to 19XX/20XX
+        assert_eq!(parse(&mut "10").unwrap(), 2010u32);
+        assert_eq!(parse(&mut "68").unwrap(), 2068u32);
+        assert_eq!(parse(&mut "69").unwrap(), 1969u32);
+        assert_eq!(parse(&mut "99").unwrap(), 1999u32);
+
+        // 3,4-characters are converted verbatim
+        assert_eq!(parse(&mut "468").unwrap(), 468u32);
+        assert_eq!(parse(&mut "469").unwrap(), 469u32);
+        assert_eq!(parse(&mut "1568").unwrap(), 1568u32);
+        assert_eq!(parse(&mut "1569").unwrap(), 1569u32);
+
+        // years greater than 9999 are not accepted
+        assert!(parse(&mut "10000").is_err());
+    }
+}

src/lib.rs

@@ -165,7 +165,13 @@ mod tests {
 
         #[test]
         fn invalid_formats() {
-            let invalid_dts = vec!["NotADate", "202104", "202104-12T22:37:47"];
+            let invalid_dts = vec![
+                "NotADate",
+                "202104",
+                "202104-12T22:37:47",
+                "a774e26sec", // 774e26 is not a valid seconds value (we don't accept E-notation)
+                "12.",        // Invalid floating point number
+            ];
             for dt in invalid_dts {
                 assert_eq!(parse_datetime(dt), Err(ParseDateTimeError::InvalidInput));
             }
@@ -216,7 +222,6 @@ mod tests {
         use chrono::{Local, NaiveDate};
 
         use crate::parse_datetime;
-        use crate::ParseDateTimeError;
 
         #[test]
         fn test_positive_offsets() {
@@ -227,8 +232,6 @@ mod tests {
                 "Z+07:00",
                 "Z+0700",
                 "Z+07",
-                "+07",
-                "+7",
             ];
 
             let expected = format!("{}{}", Local::now().format("%Y%m%d"), "0000+0700");
@@ -248,15 +251,6 @@ mod tests {
             }
         }
 
-        #[test]
-        fn invalid_offset_format() {
-            let offset = "UTC+01005";
-            assert_eq!(
-                parse_datetime(offset),
-                Err(ParseDateTimeError::InvalidInput)
-            );
-        }
-
         #[test]
         fn test_datetime_with_offset() {
             let actual = parse_datetime("1997-01-19 08:17:48 +2").unwrap();
@@ -383,21 +377,6 @@ mod tests {
         }
     }
 
-    #[cfg(test)]
-    mod timeonly {
-        use crate::parse_datetime_at_date;
-        use chrono::{Local, TimeZone};
-        use std::env;
-        #[test]
-        fn test_time_only() {
-            env::set_var("TZ", "UTC");
-            let test_date = Local.with_ymd_and_hms(2024, 3, 3, 0, 0, 0).unwrap();
-            let parsed_time = parse_datetime_at_date(test_date, "9:04:30 PM +0530")
-                .unwrap()
-                .timestamp();
-            assert_eq!(parsed_time, 1709480070);
-        }
-    }
     /// Used to test example code presented in the README.
     mod readme_test {
         use crate::parse_datetime;
@@ -463,9 +442,6 @@ mod tests {
         for s in [
             "1997-01-01 00:00:00 +0000",
             "1997-01-01 00:00:00 +00",
-            "199701010000 +0000",
-            "199701010000UTC+0000",
-            "199701010000Z+0000",
             "1997-01-01 00:00 +0000",
             "1997-01-01 00:00:00 +0000",
             "1997-01-01T00:00:00+0000",
@@ -531,9 +507,6 @@ mod tests {
         for s in [
             "1997-01-01 00:00:00 +0000 +1 year",
             "1997-01-01 00:00:00 +00 +1 year",
-            "199701010000 +0000 +1 year",
-            "199701010000UTC+0000 +1 year",
-            "199701010000Z+0000 +1 year",
             "1997-01-01T00:00:00Z +1 year",
             "1997-01-01 00:00 +0000 +1 year",
             "1997-01-01 00:00:00 +0000 +1 year",
@@ -596,22 +569,6 @@ mod tests {
         }
     }
 
-    #[test]
-    fn test_time_only() {
-        use chrono::{FixedOffset, Local};
-        std::env::set_var("TZ", "UTC");
-
-        let offset = FixedOffset::east_opt(5 * 60 * 60 + 1800).unwrap();
-        let expected = Local::now()
-            .date_naive()
-            .and_hms_opt(21, 4, 30)
-            .unwrap()
-            .and_local_timezone(offset)
-            .unwrap();
-        let actual = crate::parse_datetime("9:04:30 PM +0530").unwrap();
-        assert_eq!(actual, expected);
-    }
-
     #[test]
     fn test_weekday_only() {
         use chrono::{Datelike, Days, Local, MappedLocalTime, NaiveTime, Weekday};

tests/common/mod.rs

@@ -0,0 +1,33 @@
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use std::env;
+
+use chrono::{DateTime, FixedOffset};
+use parse_datetime::{parse_datetime, parse_datetime_at_date};
+
+pub fn check_absolute(input: &str, expected: &str) {
+    env::set_var("TZ", "UTC0");
+
+    let parsed = match parse_datetime(input) {
+        Ok(v) => v,
+        Err(e) => panic!("Failed to parse date from value '{input}': {e}"),
+    };
+
+    assert_eq!(
+        &parsed.to_rfc3339().replace("T", " "),
+        expected,
+        "Input value: {input}"
+    );
+}
+
+pub fn check_relative(now: DateTime<FixedOffset>, input: &str, expected: &str) {
+    env::set_var("TZ", "UTC0");
+
+    let parsed = match parse_datetime_at_date(now.into(), input) {
+        Ok(v) => v,
+        Err(e) => panic!("Failed to parse date from value '{input}': {e}"),
+    };
+    let expected_parsed = DateTime::parse_from_rfc3339(expected).unwrap();
+    assert_eq!(parsed, expected_parsed, "Input value: {input}");
+}

tests/date.rs

@@ -0,0 +1,95 @@
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use rstest::rstest;
+
+mod common;
+use common::check_absolute;
+
+// The expected values are produced by GNU date version 8.32
+// export LC_TIME=en_US.UTF-8
+// export TZ=UTC
+// date --rfc-3339=seconds --date="2022-11-14"
+//
+// Documentation for the date format can be found at:
+// https://www.gnu.org/software/coreutils/manual/html_node/Calendar-date-items.html
+
+#[rstest]
+#[case::iso8601("2022-11-14", "2022-11-14 00:00:00+00:00")]
+#[case::short_year_22("22-11-14", "2022-11-14 00:00:00+00:00")]
+#[case::short_year_68("68-11-14", "2068-11-14 00:00:00+00:00")]
+#[case::short_year_00("00-11-14", "2000-11-14 00:00:00+00:00")]
+#[case::short_year_69("69-11-14", "1969-11-14 00:00:00+00:00")]
+#[case::short_year_99("99-11-14", "1999-11-14 00:00:00+00:00")]
+#[case::us_style("11/14/2022", "2022-11-14 00:00:00+00:00")]
+#[case::us_style_short_year("11/14/22", "2022-11-14 00:00:00+00:00")]
+#[case::year_zero("0000-01-01", "0000-01-01 00:00:00+00:00")]
+#[case::year_001("001-11-14", "0001-11-14 00:00:00+00:00")]
+#[case::year_100("100-11-14", "0100-11-14 00:00:00+00:00")]
+#[case::year_999("999-11-14", "0999-11-14 00:00:00+00:00")]
+#[case::year_9999("9999-11-14", "9999-11-14 00:00:00+00:00")]
+/** TODO: https://github.com/uutils/parse_datetime/issues/160
+#[case::year_10000("10000-12-31", "10000-12-31 00:00:00+00:00")]
+#[case::year_100000("100000-12-31", "100000-12-31 00:00:00+00:00")]
+#[case::year_1000000("1000000-12-31", "1000000-12-31 00:00:00+00:00")]
+#[case::year_10000000("10000000-12-31", "10000000-12-31 00:00:00+00:00")]
+#[case::max_date("2147485547-12-31", "2147485547-12-31 00:00:00+00:00")]
+**/
+#[case::long_month_in_the_middle("14 November 2022", "2022-11-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_lowercase("14 november 2022", "2022-11-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_uppercase("14 NOVEMBER 2022", "2022-11-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle("14 nov 2022", "2022-11-14 00:00:00+00:00")]
+#[case::short_month_in_the_uppercase("14 NOV 2022", "2022-11-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_hyphened("14-november-2022", "2022-11-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_nospace("14november2022", "2022-11-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_hyphened("14-nov-2022", "2022-11-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_nospace("14nov2022", "2022-11-14 00:00:00+00:00")]
+#[case::long_month_at_start("November 14 2022", "2022-11-14 00:00:00+00:00")]
+#[case::long_month_at_start_with_comma("November 14, 2022", "2022-11-14 00:00:00+00:00")]
+#[case::short_month_at_start("nov 14 2022", "2022-11-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_jan("14 January 2022", "2022-01-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_feb("14 February 2022", "2022-02-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_mar("14 March 2022", "2022-03-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_apr("14 April 2022", "2022-04-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_may("14 May 2022", "2022-05-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_jun("14 June 2022", "2022-06-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_jul("14 July 2022", "2022-07-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_aug("14 August 2022", "2022-08-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_sep("14 September 2022", "2022-09-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_oct("14 October 2022", "2022-10-14 00:00:00+00:00")]
+#[case::long_month_in_the_middle_dec("14 December 2022", "2022-12-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_jan("14 jan 2022", "2022-01-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_feb("14 feb 2022", "2022-02-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_mar("14 mar 2022", "2022-03-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_apr("14 apr 2022", "2022-04-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_may("14 may 2022", "2022-05-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_jun("14 jun 2022", "2022-06-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_jul("14 jul 2022", "2022-07-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_aug("14 aug 2022", "2022-08-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_sep("14 sep 2022", "2022-09-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_sept("14 sept 2022", "2022-09-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_oct("14 oct 2022", "2022-10-14 00:00:00+00:00")]
+#[case::short_month_in_the_middle_dec("14 dec 2022", "2022-12-14 00:00:00+00:00")]
+fn test_absolute_date_numeric(#[case] input: &str, #[case] expected: &str) {
+    check_absolute(input, expected);
+}
+
+#[rstest]
+#[case::us_style("11/14", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_full_month_in_front("november 14", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_full_month_at_back("14 november", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_short_month_in_front("nov 14", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_short_month_at_back("14 nov", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_full_month_in_front("november 14", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_full_month_at_back("14 november", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_short_month_in_front("nov 14", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_short_month_at_back("14 nov", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_long_month_at_back_hyphen("14-november", 2022, "2022-11-14 00:00:00+00:00")]
+#[case::alphabetical_short_month_at_back_hyphen("14-nov", 2022, "2022-11-14 00:00:00+00:00")]
+fn test_date_omitting_year(#[case] input: &str, #[case] year: u32, #[case] expected: &str) {
+    use chrono::DateTime;
+    use common::check_relative;
+
+    let now = DateTime::parse_from_rfc3339(&format!("{year}-06-01T00:00:00+00:00")).unwrap();
+    check_relative(now, input, expected);
+}

tests/simple.rs

@@ -1 +0,0 @@
-