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use super::Span;
impl Span<'_> {
/// Return a new span, discarding the first `n` characters in the input
/// span.
pub(crate) fn discard(self, n: usize) -> Self {
self.into_parse_result(n).after
}
/// Return a new span, discarding any whitespace found at the beginning of
/// the input span.
pub(crate) fn discard_whitespace(self) -> Self {
self.take_whitespace().after
}
/// Return a new span, discarding all characters in the input span.
pub(crate) fn discard_all(self) -> Self {
self.discard(self.len())
}
}
#[cfg(test)]
mod tests {
#![allow(clippy::unwrap_used)]
mod discard {
use crate::tests::prelude::*;
#[test]
fn empty_source() {
let span = crate::Span::default();
assert_eq!(
span.discard(4),
Span {
data: "",
line: 1,
col: 1,
offset: 0,
}
);
}
#[test]
fn n_gt_len() {
let span = crate::Span::new("abc");
assert_eq!(
span.discard(6),
Span {
data: "",
line: 1,
col: 4,
offset: 3,
}
);
}
#[test]
fn n_eq_len() {
let span = crate::Span::new("abc");
assert_eq!(
span.discard(3),
Span {
data: "",
line: 1,
col: 4,
offset: 3,
}
);
}
#[test]
fn n_lt_len() {
let span = crate::Span::new("abc");
assert_eq!(
span.discard(2),
Span {
data: "c",
line: 1,
col: 3,
offset: 2,
}
);
}
#[test]
fn zero() {
let span = crate::Span::new("abc");
assert_eq!(
span.discard(0),
Span {
data: "abc",
line: 1,
col: 1,
offset: 0,
}
);
}
}
mod discard_whitespace {
use crate::tests::prelude::*;
#[test]
fn empty_source() {
let span = crate::Span::default();
assert_eq!(
span.discard_whitespace(),
Span {
data: "",
line: 1,
col: 1,
offset: 0,
}
);
}
#[test]
fn all_whitespace() {
let span = crate::Span::new(" \t ");
assert_eq!(
span.discard_whitespace(),
Span {
data: "",
line: 1,
col: 7,
offset: 6,
}
);
}
#[test]
fn doesnt_consume_newline() {
let span = crate::Span::new(" \nabc");
assert_eq!(
span.discard_whitespace(),
Span {
data: "\nabc",
line: 1,
col: 4,
offset: 3,
}
);
}
#[test]
fn some_whitespace() {
let span = crate::Span::new(" abc");
assert_eq!(
span.discard_whitespace(),
Span {
data: "abc",
line: 1,
col: 4,
offset: 3,
}
);
}
#[test]
fn no_whitespace() {
let span = crate::Span::new("abc");
assert_eq!(
span.discard_whitespace(),
Span {
data: "abc",
line: 1,
col: 1,
offset: 0,
}
);
}
}
mod discard_all {
use crate::tests::prelude::*;
#[test]
fn empty_source() {
let span = crate::Span::default();
assert_eq!(
span.discard_all(),
Span {
data: "",
line: 1,
col: 1,
offset: 0,
}
);
}
#[test]
fn non_empty() {
let span = crate::Span::new("abc");
assert_eq!(
span.discard(3),
Span {
data: "",
line: 1,
col: 4,
offset: 3,
}
);
}
}
}