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|
use crate::{
TextRange,
string_lexing::{
parser::Parser,
StringComponent,
}};
pub fn parse_string_literal(src: &str) -> StringComponentIterator {
StringComponentIterator {
parser: Parser::new(src, b'"'),
has_closing_quote: false,
suffix: None,
prefix: None,
quote: b'"',
}
}
pub fn parse_byte_string_literal(src: &str) -> StringComponentIterator {
StringComponentIterator {
parser: Parser::new(src, b'"'),
has_closing_quote: false,
suffix: None,
prefix: Some(b'b'),
quote: b'"',
}
}
pub fn parse_char_literal(src: &str) -> StringComponentIterator {
StringComponentIterator {
parser: Parser::new(src, b'\''),
has_closing_quote: false,
suffix: None,
prefix: None,
quote: b'\'',
}
}
pub fn parse_byte_literal(src: &str) -> StringComponentIterator {
StringComponentIterator {
parser: Parser::new(src, b'\''),
has_closing_quote: false,
suffix: None,
prefix: Some(b'b'),
quote: b'\'',
}
}
pub struct StringComponentIterator<'a> {
parser: Parser<'a>,
pub has_closing_quote: bool,
pub suffix: Option<TextRange>,
prefix: Option<u8>,
quote: u8,
}
impl<'a> Iterator for StringComponentIterator<'a> {
type Item = StringComponent;
fn next(&mut self) -> Option<StringComponent> {
if self.parser.pos == 0 {
if let Some(prefix) = self.prefix {
assert!(
self.parser.advance() == prefix as char,
"literal should start with a {:?}",
prefix as char,
);
}
assert!(
self.parser.advance() == self.quote as char,
"literal should start with a {:?}",
self.quote as char,
);
}
if let Some(component) = self.parser.parse_component() {
return Some(component);
}
// We get here when there are no char components left to parse
if self.parser.peek() == Some(self.quote as char) {
self.parser.advance();
self.has_closing_quote = true;
if let Some(range) = self.parser.parse_suffix() {
self.suffix = Some(range);
}
}
assert!(
self.parser.peek() == None,
"literal should leave no unparsed input: src = {:?}, pos = {}, length = {}",
self.parser.src,
self.parser.pos,
self.parser.src.len()
);
None
}
}
#[cfg(test)]
mod tests {
use rowan::TextRange;
use crate::string_lexing::{
StringComponent,
StringComponentKind::*,
};
fn parse(src: &str) -> (bool, Vec<StringComponent>) {
let component_iterator = &mut super::parse_char_literal(src);
let components: Vec<_> = component_iterator.collect();
(component_iterator.has_closing_quote, components)
}
fn unclosed_char_component(src: &str) -> StringComponent {
let (has_closing_quote, components) = parse(src);
assert!(!has_closing_quote, "char should not have closing quote");
assert!(components.len() == 1);
components[0].clone()
}
fn closed_char_component(src: &str) -> StringComponent {
let (has_closing_quote, components) = parse(src);
assert!(has_closing_quote, "char should have closing quote");
assert!(components.len() == 1, "Literal: {}\nComponents: {:#?}", src, components);
components[0].clone()
}
fn closed_char_components(src: &str) -> Vec<StringComponent> {
let (has_closing_quote, components) = parse(src);
assert!(has_closing_quote, "char should have closing quote");
components
}
fn range_closed(src: &str) -> TextRange {
TextRange::from_to(1.into(), (src.len() as u32 - 1).into())
}
fn range_unclosed(src: &str) -> TextRange {
TextRange::from_to(1.into(), (src.len() as u32).into())
}
#[test]
fn test_unicode_escapes() {
let unicode_escapes = &[r"{DEAD}", "{BEEF}", "{FF}", "{}", ""];
for escape in unicode_escapes {
let escape_sequence = format!(r"'\u{}'", escape);
let component = closed_char_component(&escape_sequence);
let expected_range = range_closed(&escape_sequence);
assert_eq!(component.kind, UnicodeEscape);
assert_eq!(component.range, expected_range);
}
}
#[test]
fn test_unicode_escapes_unclosed() {
let unicode_escapes = &["{DEAD", "{BEEF", "{FF"];
for escape in unicode_escapes {
let escape_sequence = format!(r"'\u{}'", escape);
let component = unclosed_char_component(&escape_sequence);
let expected_range = range_unclosed(&escape_sequence);
assert_eq!(component.kind, UnicodeEscape);
assert_eq!(component.range, expected_range);
}
}
#[test]
fn test_empty_char() {
let (has_closing_quote, components) = parse("''");
assert!(has_closing_quote, "char should have closing quote");
assert!(components.len() == 0);
}
#[test]
fn test_unclosed_char() {
let component = unclosed_char_component("'a");
assert!(component.kind == CodePoint);
assert!(component.range == TextRange::from_to(1.into(), 2.into()));
}
#[test]
fn test_digit_escapes() {
let literals = &[r"", r"5", r"55"];
for literal in literals {
let lit_text = format!(r"'\x{}'", literal);
let component = closed_char_component(&lit_text);
assert!(component.kind == AsciiCodeEscape);
assert!(component.range == range_closed(&lit_text));
}
// More than 2 digits starts a new codepoint
let components = closed_char_components(r"'\x555'");
assert!(components.len() == 2);
assert!(components[1].kind == CodePoint);
}
#[test]
fn test_ascii_escapes() {
let literals = &[
r"\'", "\\\"", // equivalent to \"
r"\n", r"\r", r"\t", r"\\", r"\0",
];
for literal in literals {
let lit_text = format!("'{}'", literal);
let component = closed_char_component(&lit_text);
assert!(component.kind == AsciiEscape);
assert!(component.range == range_closed(&lit_text));
}
}
#[test]
fn test_no_escapes() {
let literals = &['"', 'n', 'r', 't', '0', 'x', 'u'];
for &literal in literals {
let lit_text = format!("'{}'", literal);
let component = closed_char_component(&lit_text);
assert!(component.kind == CodePoint);
assert!(component.range == range_closed(&lit_text));
}
}
}
|
