Add timezone parsing

Author: sharkdp

numbat/src/datetime.rs

@@ -41,12 +41,30 @@ pub fn parse_datetime(input: &str) -> Result<Option<DateTime<FixedOffset>>, Pars
         ];
 
         for format in FORMATS {
-            // With UTC offset
+            // Try to match the given format plus an additional UTC offset (%z)
             if let Ok(dt) = chrono::DateTime::parse_from_str(input, &format!("{format} %z")) {
                 return Ok(Some(dt));
             }
 
-            // Without offset
+            // Try to match the given format plus an additional timezone name (%Z).
+            // chrono does not support %Z, so we implement this ourselves. We were
+            // warned by developers before us not to write timezone-related code on
+            // our own, so we're probably going to regret this.
+
+            // Get the last space-separated word in the input string, and try to parse it
+            // as a timezone specifier, then try to match the rest of the string with the
+            // given format.
+            if let Some((rest, potential_timezone_name)) = input.rsplit_once(' ') {
+                if let Ok(tz) = potential_timezone_name.parse::<Tz>() {
+                    if let Ok(ndt) = chrono::NaiveDateTime::parse_from_str(rest, format) {
+                        if let LocalResult::Single(dt) = ndt.and_local_timezone(tz) {
+                            return Ok(Some(dt.with_timezone(&local_offset_for_datetime(&dt))));
+                        }
+                    }
+                }
+            }
+
+            // Without timezone/offset
             if let Ok(ndt) = chrono::NaiveDateTime::parse_from_str(input, format) {
                 if let LocalResult::Single(dt) =
                     ndt.and_local_timezone(get_local_timezone().unwrap_or(chrono_tz::UTC))