Merge pull request #137 from yuankunzhang/replace-the-regex-parser

Replace the regex parser with winnow-based parse

Author: tertsdiepraam

Cargo.lock

@@ -11,3 +11,5 @@ readme = "README.md"
 regex = "1.10.4"
 chrono = { version="0.4.38", default-features=false, features=["std", "alloc", "clock"] }
 nom = "8.0.0"
+winnow = "0.5.34"
+num-traits = "0.2.19"

Cargo.toml

@@ -0,0 +1,75 @@
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+//! Parse an ISO 8601 date and time item
+//!
+//! The GNU docs state:
+//!
+//! > The ISO 8601 date and time of day extended format consists of an ISO 8601
+//! > date, a ‘T’ character separator, and an ISO 8601 time of day. This format
+//! > is also recognized if the ‘T’ is replaced by a space.
+//! >
+//! > 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.
+use winnow::{combinator::alt, seq, trace::trace, PResult, Parser};
+
+use crate::items::space;
+
+use super::{
+    date::{self, Date},
+    s,
+    time::{self, Time},
+};
+
+#[derive(PartialEq, Debug, Clone, Default)]
+pub struct DateTime {
+    pub(crate) date: Date,
+    pub(crate) time: Time,
+}
+
+pub fn parse(input: &mut &str) -> PResult<DateTime> {
+    seq!(DateTime {
+        date: trace("date iso", 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),
+    })
+    .parse_next(input)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{parse, DateTime};
+    use crate::items::{date::Date, time::Time};
+
+    #[test]
+    fn some_date() {
+        let reference = Some(DateTime {
+            date: Date {
+                day: 10,
+                month: 10,
+                year: Some(2022),
+            },
+            time: Time {
+                hour: 10,
+                minute: 10,
+                second: 55.0,
+                offset: None,
+            },
+        });
+
+        for mut s in [
+            "2022-10-10t10:10:55",
+            "2022-10-10 10:10:55",
+            "2022-10-10    t   10:10:55",
+            "2022-10-10       10:10:55",
+            "2022-10-10  (A comment!) t   10:10:55",
+            "2022-10-10  (A comment!)   10:10:55",
+        ] {
+            let old_s = s.to_owned();
+            assert_eq!(parse(&mut s).ok(), reference, "Failed string: {old_s}")
+        }
+    }
+}