1
0
mirror of https://github.com/bspeice/dtparse synced 2024-12-22 12:28:08 -05:00

Write ALL the documentation!

This commit is contained in:
Bradlee Speice 2018-08-01 23:27:49 -04:00
parent 256f937742
commit 8f8ba7887a

View File

@ -1,4 +1,4 @@
// #![deny(missing_docs)] #![deny(missing_docs)]
#![cfg_attr(test, deny(warnings))] #![cfg_attr(test, deny(warnings))]
//! # dtparse //! # dtparse
@ -11,8 +11,8 @@
//! from the test cases should give some context: //! from the test cases should give some context:
//! //!
//! ```rust //! ```rust
//! extern crate chrono; //! # extern crate chrono;
//! extern crate dtparse; //! # extern crate dtparse;
//! use chrono::prelude::*; //! use chrono::prelude::*;
//! use dtparse::parse; //! use dtparse::parse;
//! //!
@ -35,11 +35,11 @@
//! only content if we dig into the implementation a bit! //! only content if we dig into the implementation a bit!
//! //!
//! ```rust //! ```rust
//! extern crate chrono; //! # extern crate chrono;
//! extern crate dtparse; //! # extern crate dtparse;
//! use chrono::prelude::*; //! use chrono::prelude::*;
//! use dtparse::Parser; //! use dtparse::Parser;
//! use std::collections::HashMap; //! # use std::collections::HashMap;
//! //!
//! let mut p = Parser::default(); //! let mut p = Parser::default();
//! assert_eq!( //! assert_eq!(
@ -116,16 +116,25 @@ impl From<ParseIntError> for ParseError {
} }
} }
/// Potential errors that come up when trying to parse time strings
#[derive(Debug, PartialEq)] #[derive(Debug, PartialEq)]
pub enum ParseError { pub enum ParseError {
AmbiguousYMD, /// Attempted to specify "AM" or "PM" without indicating an hour
AmbiguousWeekday,
AmPmWithoutHour, AmPmWithoutHour,
/// Impossible value for a category; the 32nd day of a month is impossible
ImpossibleTimestamp(&'static str), ImpossibleTimestamp(&'static str),
/// Unable to parse a numeric value from a token expected to be numeric
InvalidNumeric(String), InvalidNumeric(String),
/// Generally unrecognized date string; please report to maintainer so
/// new test cases can be developed
UnrecognizedFormat, UnrecognizedFormat,
/// A token the parser did not recognize was in the string, and fuzzy mode was off
UnrecognizedToken(String), UnrecognizedToken(String),
/// A timezone could not be handled; please report to maintainer as the timestring
/// likely exposes a bug in the implementation
TimezoneUnsupported, TimezoneUnsupported,
/// Parser unable to make sense of year/month/day parameters in the time string;
/// please report to maintainer as the timestring likely exposes a bug in implementation
YearMonthDayError(&'static str), YearMonthDayError(&'static str),
} }
@ -136,7 +145,9 @@ pub(crate) fn tokenize(parse_string: &str) -> Vec<String> {
tokenizer.collect() tokenizer.collect()
} }
fn parse_info(vec: Vec<Vec<&str>>) -> HashMap<String, usize> { /// Utility function for `ParserInfo` that helps in constructing
/// the attributes that make up the `ParserInfo` container
pub fn parse_info(vec: Vec<Vec<&str>>) -> HashMap<String, usize> {
let mut m = HashMap::new(); let mut m = HashMap::new();
if vec.len() == 1 { if vec.len() == 1 {
@ -154,6 +165,23 @@ fn parse_info(vec: Vec<Vec<&str>>) -> HashMap<String, usize> {
m m
} }
/// Container for specific tokens to be recognized during parsing.
///
/// - `jump`: Values that indicate the end of a token for parsing and can be ignored
/// - `weekday`: Names of the days of the week
/// - `months`: Names of the months
/// - `hms`: Names for the units of time - hours, minutes, seconds in English
/// - `ampm`: AM and PM tokens
/// - `utczone`: Tokens indicating a UTC-timezone string
/// - `pertain`: Tokens indicating a "belongs to" relationship; in English this is just "of"
/// - `tzoffset`:
/// - `dayfirst`: Upon encountering an ambiguous date, treat the first value as the day
/// - `yearfirst`: Upon encountering an ambiguous date, treat the first value as the year
/// - `year`: The current year
/// - `century`: The first year in the current century
///
/// Please note that if both `dayfirst` and `yearfirst` are true, years take precedence
/// and will be parsed as "YDM"
#[derive(Debug, PartialEq)] #[derive(Debug, PartialEq)]
pub struct ParserInfo { pub struct ParserInfo {
jump: HashMap<String, usize>, jump: HashMap<String, usize>,
@ -171,6 +199,7 @@ pub struct ParserInfo {
} }
impl Default for ParserInfo { impl Default for ParserInfo {
/// Create a basic `ParserInfo` object suitable for parsing dates in English
fn default() -> Self { fn default() -> Self {
let year = Local::now().year(); let year = Local::now().year();
let century = year / 100 * 100; let century = year / 100 * 100;
@ -568,16 +597,54 @@ struct ParsingResult {
any_unused_tokens: Vec<String>, any_unused_tokens: Vec<String>,
} }
/// Parser is responsible for doing the actual work of understanding a time string.
/// The root level `parse` function is responsible for constructing a default `Parser`
/// and triggering its behavior.
#[derive(Default)] #[derive(Default)]
pub struct Parser { pub struct Parser {
info: ParserInfo, info: ParserInfo,
} }
impl Parser { impl Parser {
/// Create a new `Parser` instance using the provided `ParserInfo`.
///
/// This method allows you to set up a parser to handle different
/// names for days of the week, months, etc., enabling customization
/// for different languages or extra values.
pub fn new(info: ParserInfo) -> Self { pub fn new(info: ParserInfo) -> Self {
Parser { info } Parser { info }
} }
/// Main method to trigger parsing of a string using the previously-provided
/// parser information. Returns a naive timestamp along with timezone and
/// unused tokens if available.
///
/// `dayfirst` and `yearfirst` force parser behavior in the event of ambiguous
/// dates. Consider the following scenarios where we parse the string '01.02.03'
///
/// - `dayfirst=Some(true)`, `yearfirst=None`: Results in `February 2, 2003`
/// - `dayfirst=None`, `yearfirst=Some(true)`: Results in `February 3, 2001`
/// - `dayfirst=Some(true)`, `yearfirst=Some(true)`: Results in `March 2, 2001`
///
/// `fuzzy` enables fuzzy parsing mode, allowing the parser to skip tokens if
/// they are unrecognized. However, the unused tokens will not be returned
/// unless `fuzzy_with_tokens` is set as `true`.
///
/// `default` is the timestamp used to infer missing values, and is midnight
/// of the current day by default. For example, when parsing the text '2003',
/// we will use the current month and day as a default value, leading to a
/// result of 'March 3, 2003' if the function was run using a default of
/// March 3rd.
///
/// `ignoretz` forces the parser to ignore timezone information even if it
/// is recognized in the time string
///
/// `tzinfos` is a map of timezone names to the offset seconds. For example,
/// the parser would ignore the 'EST' part of the string in '10 AM EST'
/// unless you added a `tzinfos` map of `{"EST": "14400"}`. Please note that
/// timezone name support (i.e. "EST", "BRST") is not available by default
/// at the moment, they must be added through `tzinfos` at the moment in
/// order to be resolved.
pub fn parse( pub fn parse(
&mut self, &mut self,
timestr: &str, timestr: &str,
@ -1187,6 +1254,12 @@ fn ljust(s: &str, chars: usize, replace: char) -> String {
} }
} }
/// Main entry point for using `dtparse`. The parse function is responsible for
/// taking in a string representing some time value, and turning it into
/// a timestamp with optional timezone information if it can be identified.
///
/// The default implementation assumes English values for names of months,
/// days of the week, etc. It is equivalent to Python's `dateutil.parser.parse()`
pub fn parse(timestr: &str) -> ParseResult<(NaiveDateTime, Option<FixedOffset>)> { pub fn parse(timestr: &str) -> ParseResult<(NaiveDateTime, Option<FixedOffset>)> {
let res = Parser::default().parse( let res = Parser::default().parse(
timestr, timestr,