Add %#z as "Permissive" timezone parsing

This allows you to parse a timezone that:

* Is either `Z` or an actual offset
* Contains no minutes, just the hour

Fixes #219
This commit is contained in:
Brandon W Maister 2018-04-24 22:11:37 -04:00
parent 9276929c58
commit 95f6a2be1c
4 changed files with 77 additions and 12 deletions

View File

@ -200,6 +200,15 @@ pub enum Fixed {
/// Same to [`TimezoneOffsetColonZ`](#variant.TimezoneOffsetColonZ) but prints no colon.
/// Parsing allows an optional colon.
TimezoneOffsetZ,
/// Same as [`TimezoneOffsetColonZ`](#variant.TimezoneOffsetColonZ), but
/// allows missing minutes (per [ISO 8601][iso8601]).
///
/// # Panics
///
/// If you try to use this for printing.
///
/// [iso8601]: https://en.wikipedia.org/wiki/ISO_8601#Time_offsets_from_UTC
TimezoneOffsetPermissive,
/// RFC 2822 date and time syntax. Commonly used for email and MIME date and time.
RFC2822,
/// RFC 3339 & ISO 8601 date and time syntax.
@ -491,6 +500,8 @@ pub fn format<'a, I>(w: &mut fmt::Formatter, date: Option<&NaiveDate>, time: Opt
off.map(|&(_, off)| write_local_minus_utc(w, off, false, false)),
TimezoneOffsetZ =>
off.map(|&(_, off)| write_local_minus_utc(w, off, true, false)),
TimezoneOffsetPermissive =>
panic!("Do not try to write %#z it is undefined"),
RFC2822 => // same to `%a, %e %b %Y %H:%M:%S %z`
if let (Some(d), Some(t), Some(&(_, off))) = (date, time, off) {
let sec = t.second() + t.nanosecond() / 1_000_000_000;
@ -609,4 +620,3 @@ impl FromStr for Weekday {
}
}
}

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@ -328,6 +328,11 @@ pub fn parse<'a, I>(parsed: &mut Parsed, mut s: &str, items: I) -> ParseResult<(
scan::colon_or_space));
try!(parsed.set_offset(i64::from(offset)));
}
TimezoneOffsetPermissive => {
let offset = try_consume!(scan::timezone_offset_permissive(
s.trim_left(), scan::colon_or_space));
try!(parsed.set_offset(i64::from(offset)));
}
RFC2822 => try_consume!(parse_rfc2822(parsed, s)),
RFC3339 => try_consume!(parse_rfc3339(parsed, s)),
@ -570,6 +575,10 @@ fn test_parse() {
check!("zulu", [fix!(TimezoneOffsetZ), lit!("ulu")]; offset: 0);
check!("+1234ulu", [fix!(TimezoneOffsetZ), lit!("ulu")]; offset: 754 * 60);
check!("+12:34ulu", [fix!(TimezoneOffsetZ), lit!("ulu")]; offset: 754 * 60);
check!("Z", [fix!(TimezoneOffsetPermissive)]; offset: 0);
check!("z", [fix!(TimezoneOffsetPermissive)]; offset: 0);
check!("+12:00", [fix!(TimezoneOffsetPermissive)]; offset: 12 * 60 * 60);
check!("+12", [fix!(TimezoneOffsetPermissive)]; offset: 12 * 60 * 60);
check!("???", [fix!(TimezoneName)]; BAD_FORMAT); // not allowed
// some practical examples

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@ -171,8 +171,15 @@ pub fn colon_or_space(s: &str) -> ParseResult<&str> {
///
/// The additional `colon` may be used to parse a mandatory or optional `:`
/// between hours and minutes, and should return either a new suffix or `Err` when parsing fails.
pub fn timezone_offset<F>(mut s: &str, mut colon: F) -> ParseResult<(&str, i32)>
pub fn timezone_offset<F>(s: &str, consume_colon: F) -> ParseResult<(&str, i32)>
where F: FnMut(&str) -> ParseResult<&str> {
timezone_offset_internal(s, consume_colon, false)
}
fn timezone_offset_internal<F>(mut s: &str, mut consume_colon: F, allow_missing_minutes: bool)
-> ParseResult<(&str, i32)>
where F: FnMut(&str) -> ParseResult<&str>
{
fn digits(s: &str) -> ParseResult<(u8, u8)> {
let b = s.as_bytes();
if b.len() < 2 {
@ -197,29 +204,54 @@ pub fn timezone_offset<F>(mut s: &str, mut colon: F) -> ParseResult<(&str, i32)>
s = &s[2..];
// colons (and possibly other separators)
s = try!(colon(s));
s = try!(consume_colon(s));
// minutes (00--59)
let minutes = match try!(digits(s)) {
// if the next two items are digits then we have to add minutes
let minutes = if let Ok(ds) = digits(s) {
match ds {
(m1 @ b'0'...b'5', m2 @ b'0'...b'9') => i32::from((m1 - b'0') * 10 + (m2 - b'0')),
(b'6'...b'9', b'0'...b'9') => return Err(OUT_OF_RANGE),
_ => return Err(INVALID),
}
} else if allow_missing_minutes {
0
} else {
return Err(TOO_SHORT);
};
s = match s.len() {
len if len >= 2 => &s[2..],
len if len == 0 => s,
_ => return Err(TOO_SHORT),
};
s = &s[2..];
let seconds = hours * 3600 + minutes * 60;
Ok((s, if negative {-seconds} else {seconds}))
}
/// Same to `timezone_offset` but also allows for `z`/`Z` which is same to `+00:00`.
pub fn timezone_offset_zulu<F>(s: &str, colon: F) -> ParseResult<(&str, i32)>
where F: FnMut(&str) -> ParseResult<&str> {
pub fn timezone_offset_zulu<F>(s: &str, colon: F)
-> ParseResult<(&str, i32)>
where F: FnMut(&str) -> ParseResult<&str>
{
match s.as_bytes().first() {
Some(&b'z') | Some(&b'Z') => Ok((&s[1..], 0)),
_ => timezone_offset(s, colon),
}
}
/// Same to `timezone_offset` but also allows for `z`/`Z` which is same to
/// `+00:00`, and allows missing minutes entirely.
pub fn timezone_offset_permissive<F>(s: &str, colon: F)
-> ParseResult<(&str, i32)>
where F: FnMut(&str) -> ParseResult<&str>
{
match s.as_bytes().first() {
Some(&b'z') | Some(&b'Z') => Ok((&s[1..], 0)),
_ => timezone_offset_internal(s, colon, true),
}
}
/// Same to `timezone_offset` but also allows for RFC 2822 legacy timezones.
/// May return `None` which indicates an insufficient offset data (i.e. `-0000`).
pub fn timezone_offset_2822(s: &str) -> ParseResult<(&str, Option<i32>)> {

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@ -68,6 +68,7 @@ The following specifiers are available both to formatting and parsing.
| `%Z` | `ACST` | *Formatting only:* Local time zone name. |
| `%z` | `+0930` | Offset from the local time to UTC (with UTC being `+0000`). |
| `%:z` | `+09:30` | Same to `%z` but with a colon. |
| `%#z` | `+09` | *Parsing only:* Same to `%z` but allows minutes to be missing or present. |
| | | |
| | | **DATE & TIME SPECIFIERS:** |
|`%c`|`Sun Jul 8 00:34:60 2001`|`ctime` date & time format. Same to `%a %b %e %T %Y` sans `\n`.|
@ -167,6 +168,8 @@ impl<'a> StrftimeItems<'a> {
}
}
const HAVE_ALTERNATES: &str = "z";
impl<'a> Iterator for StrftimeItems<'a> {
type Item = Item<'a>;
@ -205,7 +208,11 @@ impl<'a> Iterator for StrftimeItems<'a> {
'_' => Some(Pad::Space),
_ => None,
};
let spec = if pad_override.is_some() { next!() } else { spec };
let is_alternate = spec == '#';
let spec = if pad_override.is_some() || is_alternate { next!() } else { spec };
if is_alternate && !HAVE_ALTERNATES.contains(spec) {
return Some(Item::Error);
}
macro_rules! recons {
[$head:expr, $($tail:expr),+] => ({
@ -262,7 +269,11 @@ impl<'a> Iterator for StrftimeItems<'a> {
'x' => recons![num0!(Month), lit!("/"), num0!(Day), lit!("/"),
num0!(YearMod100)],
'y' => num0!(YearMod100),
'z' => fix!(TimezoneOffset),
'z' => if is_alternate {
fix!(TimezoneOffsetPermissive)
} else {
fix!(TimezoneOffset)
},
'+' => fix!(RFC3339),
':' => match next!() {
'z' => fix!(TimezoneOffsetColon),
@ -368,6 +379,9 @@ fn test_strftime_items() {
assert_eq!(parse_and_collect("%-e"), [num!(Day)]);
assert_eq!(parse_and_collect("%0e"), [num0!(Day)]);
assert_eq!(parse_and_collect("%_e"), [nums!(Day)]);
assert_eq!(parse_and_collect("%z"), [fix!(TimezoneOffset)]);
assert_eq!(parse_and_collect("%#z"), [fix!(TimezoneOffsetPermissive)]);
assert_eq!(parse_and_collect("%#m"), [Item::Error]);
}
#[cfg(test)]