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821 lines
29 KiB
Rust
821 lines
29 KiB
Rust
//! Macro support for format strings
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//!
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//! These structures are used when parsing format strings for the compiler.
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//! Parsing does not happen at runtime: structures of `std::fmt::rt` are
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//! generated instead.
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#![doc(
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html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/",
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html_playground_url = "https://play.rust-lang.org/",
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test(attr(deny(warnings)))
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)]
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#![feature(nll)]
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#![feature(bool_to_option)]
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pub use Alignment::*;
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pub use Count::*;
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pub use Flag::*;
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pub use Piece::*;
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pub use Position::*;
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use std::iter;
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use std::str;
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use std::string;
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use rustc_span::{InnerSpan, Symbol};
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/// The type of format string that we are parsing.
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#[derive(Copy, Clone, Debug, Eq, PartialEq)]
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pub enum ParseMode {
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/// A normal format string as per `format_args!`.
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Format,
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/// An inline assembly template string for `asm!`.
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InlineAsm,
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}
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#[derive(Copy, Clone)]
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struct InnerOffset(usize);
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impl InnerOffset {
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fn to(self, end: InnerOffset) -> InnerSpan {
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InnerSpan::new(self.0, end.0)
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}
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}
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/// A piece is a portion of the format string which represents the next part
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/// to emit. These are emitted as a stream by the `Parser` class.
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#[derive(Copy, Clone, Debug, PartialEq)]
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pub enum Piece<'a> {
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/// A literal string which should directly be emitted
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String(&'a str),
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/// This describes that formatting should process the next argument (as
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/// specified inside) for emission.
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NextArgument(Argument<'a>),
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}
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/// Representation of an argument specification.
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#[derive(Copy, Clone, Debug, PartialEq)]
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pub struct Argument<'a> {
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/// Where to find this argument
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pub position: Position,
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/// How to format the argument
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pub format: FormatSpec<'a>,
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}
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/// Specification for the formatting of an argument in the format string.
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#[derive(Copy, Clone, Debug, PartialEq)]
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pub struct FormatSpec<'a> {
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/// Optionally specified character to fill alignment with.
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pub fill: Option<char>,
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/// Optionally specified alignment.
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pub align: Alignment,
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/// Packed version of various flags provided.
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pub flags: u32,
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/// The integer precision to use.
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pub precision: Count,
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/// The span of the precision formatting flag (for diagnostics).
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pub precision_span: Option<InnerSpan>,
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/// The string width requested for the resulting format.
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pub width: Count,
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/// The span of the width formatting flag (for diagnostics).
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pub width_span: Option<InnerSpan>,
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/// The descriptor string representing the name of the format desired for
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/// this argument, this can be empty or any number of characters, although
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/// it is required to be one word.
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pub ty: &'a str,
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/// The span of the descriptor string (for diagnostics).
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pub ty_span: Option<InnerSpan>,
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}
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/// Enum describing where an argument for a format can be located.
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#[derive(Copy, Clone, Debug, PartialEq)]
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pub enum Position {
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/// The argument is implied to be located at an index
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ArgumentImplicitlyIs(usize),
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/// The argument is located at a specific index given in the format
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ArgumentIs(usize),
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/// The argument has a name.
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ArgumentNamed(Symbol),
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}
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impl Position {
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pub fn index(&self) -> Option<usize> {
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match self {
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ArgumentIs(i) | ArgumentImplicitlyIs(i) => Some(*i),
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_ => None,
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}
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}
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}
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/// Enum of alignments which are supported.
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#[derive(Copy, Clone, Debug, PartialEq)]
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pub enum Alignment {
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/// The value will be aligned to the left.
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AlignLeft,
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/// The value will be aligned to the right.
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AlignRight,
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/// The value will be aligned in the center.
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AlignCenter,
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/// The value will take on a default alignment.
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AlignUnknown,
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}
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/// Various flags which can be applied to format strings. The meaning of these
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/// flags is defined by the formatters themselves.
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#[derive(Copy, Clone, Debug, PartialEq)]
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pub enum Flag {
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/// A `+` will be used to denote positive numbers.
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FlagSignPlus,
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/// A `-` will be used to denote negative numbers. This is the default.
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FlagSignMinus,
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/// An alternate form will be used for the value. In the case of numbers,
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/// this means that the number will be prefixed with the supplied string.
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FlagAlternate,
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/// For numbers, this means that the number will be padded with zeroes,
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/// and the sign (`+` or `-`) will precede them.
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FlagSignAwareZeroPad,
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/// For Debug / `?`, format integers in lower-case hexadecimal.
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FlagDebugLowerHex,
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/// For Debug / `?`, format integers in upper-case hexadecimal.
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FlagDebugUpperHex,
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}
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/// A count is used for the precision and width parameters of an integer, and
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/// can reference either an argument or a literal integer.
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#[derive(Copy, Clone, Debug, PartialEq)]
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pub enum Count {
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/// The count is specified explicitly.
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CountIs(usize),
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/// The count is specified by the argument with the given name.
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CountIsName(Symbol),
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/// The count is specified by the argument at the given index.
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CountIsParam(usize),
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/// The count is implied and cannot be explicitly specified.
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CountImplied,
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}
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pub struct ParseError {
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pub description: string::String,
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pub note: Option<string::String>,
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pub label: string::String,
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pub span: InnerSpan,
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pub secondary_label: Option<(string::String, InnerSpan)>,
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}
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/// The parser structure for interpreting the input format string. This is
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/// modeled as an iterator over `Piece` structures to form a stream of tokens
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/// being output.
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///
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/// This is a recursive-descent parser for the sake of simplicity, and if
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/// necessary there's probably lots of room for improvement performance-wise.
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pub struct Parser<'a> {
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mode: ParseMode,
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input: &'a str,
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cur: iter::Peekable<str::CharIndices<'a>>,
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/// Error messages accumulated during parsing
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pub errors: Vec<ParseError>,
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/// Current position of implicit positional argument pointer
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pub curarg: usize,
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/// `Some(raw count)` when the string is "raw", used to position spans correctly
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style: Option<usize>,
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/// Start and end byte offset of every successfully parsed argument
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pub arg_places: Vec<InnerSpan>,
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/// Characters that need to be shifted
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skips: Vec<usize>,
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/// Span of the last opening brace seen, used for error reporting
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last_opening_brace: Option<InnerSpan>,
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/// Whether the source string is comes from `println!` as opposed to `format!` or `print!`
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append_newline: bool,
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/// Whether this formatting string is a literal or it comes from a macro.
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pub is_literal: bool,
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/// Start position of the current line.
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cur_line_start: usize,
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/// Start and end byte offset of every line of the format string. Excludes
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/// newline characters and leading whitespace.
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pub line_spans: Vec<InnerSpan>,
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}
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impl<'a> Iterator for Parser<'a> {
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type Item = Piece<'a>;
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fn next(&mut self) -> Option<Piece<'a>> {
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if let Some(&(pos, c)) = self.cur.peek() {
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match c {
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'{' => {
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let curr_last_brace = self.last_opening_brace;
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let byte_pos = self.to_span_index(pos);
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self.last_opening_brace = Some(byte_pos.to(InnerOffset(byte_pos.0 + 1)));
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self.cur.next();
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if self.consume('{') {
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self.last_opening_brace = curr_last_brace;
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Some(String(self.string(pos + 1)))
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} else {
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let arg = self.argument();
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if let Some(rbrace_byte_idx) = self.must_consume('}') {
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let lbrace_inner_offset = self.to_span_index(pos);
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let rbrace_inner_offset = self.to_span_index(rbrace_byte_idx);
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if self.is_literal {
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self.arg_places.push(
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lbrace_inner_offset.to(InnerOffset(rbrace_inner_offset.0 + 1)),
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);
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}
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}
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Some(NextArgument(arg))
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}
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}
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'}' => {
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self.cur.next();
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if self.consume('}') {
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Some(String(self.string(pos + 1)))
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} else {
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let err_pos = self.to_span_index(pos);
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self.err_with_note(
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"unmatched `}` found",
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"unmatched `}`",
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"if you intended to print `}`, you can escape it using `}}`",
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err_pos.to(err_pos),
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);
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None
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}
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}
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_ => Some(String(self.string(pos))),
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}
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} else {
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if self.is_literal {
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let start = self.to_span_index(self.cur_line_start);
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let end = self.to_span_index(self.input.len());
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let span = start.to(end);
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if self.line_spans.last() != Some(&span) {
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self.line_spans.push(span);
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}
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}
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None
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}
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}
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}
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impl<'a> Parser<'a> {
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/// Creates a new parser for the given format string
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pub fn new(
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s: &'a str,
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style: Option<usize>,
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snippet: Option<string::String>,
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append_newline: bool,
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mode: ParseMode,
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) -> Parser<'a> {
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let (skips, is_literal) = find_skips_from_snippet(snippet, style);
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Parser {
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mode,
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input: s,
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cur: s.char_indices().peekable(),
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errors: vec![],
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curarg: 0,
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style,
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arg_places: vec![],
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skips,
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last_opening_brace: None,
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append_newline,
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is_literal,
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cur_line_start: 0,
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line_spans: vec![],
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}
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}
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/// Notifies of an error. The message doesn't actually need to be of type
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/// String, but I think it does when this eventually uses conditions so it
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/// might as well start using it now.
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fn err<S1: Into<string::String>, S2: Into<string::String>>(
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&mut self,
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description: S1,
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label: S2,
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span: InnerSpan,
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) {
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self.errors.push(ParseError {
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description: description.into(),
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note: None,
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label: label.into(),
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span,
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secondary_label: None,
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});
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}
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/// Notifies of an error. The message doesn't actually need to be of type
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/// String, but I think it does when this eventually uses conditions so it
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/// might as well start using it now.
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fn err_with_note<
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S1: Into<string::String>,
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S2: Into<string::String>,
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S3: Into<string::String>,
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>(
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&mut self,
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description: S1,
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label: S2,
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note: S3,
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span: InnerSpan,
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) {
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self.errors.push(ParseError {
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description: description.into(),
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note: Some(note.into()),
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label: label.into(),
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span,
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secondary_label: None,
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});
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}
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/// Optionally consumes the specified character. If the character is not at
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/// the current position, then the current iterator isn't moved and `false` is
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/// returned, otherwise the character is consumed and `true` is returned.
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fn consume(&mut self, c: char) -> bool {
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self.consume_pos(c).is_some()
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}
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/// Optionally consumes the specified character. If the character is not at
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/// the current position, then the current iterator isn't moved and `None` is
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/// returned, otherwise the character is consumed and the current position is
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/// returned.
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fn consume_pos(&mut self, c: char) -> Option<usize> {
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if let Some(&(pos, maybe)) = self.cur.peek() {
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if c == maybe {
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self.cur.next();
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return Some(pos);
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}
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}
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None
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}
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fn to_span_index(&self, pos: usize) -> InnerOffset {
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let mut pos = pos;
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// This handles the raw string case, the raw argument is the number of #
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// in r###"..."### (we need to add one because of the `r`).
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let raw = self.style.map_or(0, |raw| raw + 1);
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for skip in &self.skips {
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if pos > *skip {
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pos += 1;
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} else if pos == *skip && raw == 0 {
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pos += 1;
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} else {
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break;
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}
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}
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InnerOffset(raw + pos + 1)
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}
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/// Forces consumption of the specified character. If the character is not
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/// found, an error is emitted.
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fn must_consume(&mut self, c: char) -> Option<usize> {
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self.ws();
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if let Some(&(pos, maybe)) = self.cur.peek() {
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if c == maybe {
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self.cur.next();
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Some(pos)
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} else {
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let pos = self.to_span_index(pos);
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let description = format!("expected `'}}'`, found `{:?}`", maybe);
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let label = "expected `}`".to_owned();
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let (note, secondary_label) = if c == '}' {
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(
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Some(
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"if you intended to print `{`, you can escape it using `{{`".to_owned(),
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),
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self.last_opening_brace
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.map(|sp| ("because of this opening brace".to_owned(), sp)),
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)
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} else {
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(None, None)
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};
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self.errors.push(ParseError {
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description,
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note,
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label,
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span: pos.to(pos),
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secondary_label,
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});
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None
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}
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} else {
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let description = format!("expected `{:?}` but string was terminated", c);
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// point at closing `"`
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let pos = self.input.len() - if self.append_newline { 1 } else { 0 };
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let pos = self.to_span_index(pos);
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if c == '}' {
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let label = format!("expected `{:?}`", c);
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let (note, secondary_label) = if c == '}' {
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(
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Some(
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"if you intended to print `{`, you can escape it using `{{`".to_owned(),
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),
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self.last_opening_brace
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.map(|sp| ("because of this opening brace".to_owned(), sp)),
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)
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} else {
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(None, None)
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};
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self.errors.push(ParseError {
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description,
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note,
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label,
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span: pos.to(pos),
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secondary_label,
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});
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} else {
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self.err(description, format!("expected `{:?}`", c), pos.to(pos));
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}
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None
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}
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}
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/// Consumes all whitespace characters until the first non-whitespace character
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fn ws(&mut self) {
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while let Some(&(_, c)) = self.cur.peek() {
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if c.is_whitespace() {
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self.cur.next();
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} else {
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break;
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}
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}
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}
|
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|
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/// Parses all of a string which is to be considered a "raw literal" in a
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/// format string. This is everything outside of the braces.
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fn string(&mut self, start: usize) -> &'a str {
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// we may not consume the character, peek the iterator
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while let Some(&(pos, c)) = self.cur.peek() {
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match c {
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'{' | '}' => {
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return &self.input[start..pos];
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}
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'\n' if self.is_literal => {
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let start = self.to_span_index(self.cur_line_start);
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let end = self.to_span_index(pos);
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self.line_spans.push(start.to(end));
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self.cur_line_start = pos + 1;
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self.cur.next();
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}
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_ => {
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if self.is_literal && pos == self.cur_line_start && c.is_whitespace() {
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self.cur_line_start = pos + c.len_utf8();
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}
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self.cur.next();
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}
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}
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}
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&self.input[start..self.input.len()]
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}
|
|
|
|
/// Parses an `Argument` structure, or what's contained within braces inside the format string.
|
|
fn argument(&mut self) -> Argument<'a> {
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let pos = self.position();
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let format = match self.mode {
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ParseMode::Format => self.format(),
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|
ParseMode::InlineAsm => self.inline_asm(),
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};
|
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|
|
// Resolve position after parsing format spec.
|
|
let pos = match pos {
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Some(position) => position,
|
|
None => {
|
|
let i = self.curarg;
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self.curarg += 1;
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ArgumentImplicitlyIs(i)
|
|
}
|
|
};
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|
|
Argument { position: pos, format }
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|
}
|
|
|
|
/// Parses a positional argument for a format. This could either be an
|
|
/// integer index of an argument, a named argument, or a blank string.
|
|
/// Returns `Some(parsed_position)` if the position is not implicitly
|
|
/// consuming a macro argument, `None` if it's the case.
|
|
fn position(&mut self) -> Option<Position> {
|
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if let Some(i) = self.integer() {
|
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Some(ArgumentIs(i))
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|
} else {
|
|
match self.cur.peek() {
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Some(&(_, c)) if rustc_lexer::is_id_start(c) => {
|
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Some(ArgumentNamed(Symbol::intern(self.word())))
|
|
}
|
|
|
|
// This is an `ArgumentNext`.
|
|
// Record the fact and do the resolution after parsing the
|
|
// format spec, to make things like `{:.*}` work.
|
|
_ => None,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Parses a format specifier at the current position, returning all of the
|
|
/// relevant information in the `FormatSpec` struct.
|
|
fn format(&mut self) -> FormatSpec<'a> {
|
|
let mut spec = FormatSpec {
|
|
fill: None,
|
|
align: AlignUnknown,
|
|
flags: 0,
|
|
precision: CountImplied,
|
|
precision_span: None,
|
|
width: CountImplied,
|
|
width_span: None,
|
|
ty: &self.input[..0],
|
|
ty_span: None,
|
|
};
|
|
if !self.consume(':') {
|
|
return spec;
|
|
}
|
|
|
|
// fill character
|
|
if let Some(&(_, c)) = self.cur.peek() {
|
|
if let Some((_, '>' | '<' | '^')) = self.cur.clone().nth(1) {
|
|
spec.fill = Some(c);
|
|
self.cur.next();
|
|
}
|
|
}
|
|
// Alignment
|
|
if self.consume('<') {
|
|
spec.align = AlignLeft;
|
|
} else if self.consume('>') {
|
|
spec.align = AlignRight;
|
|
} else if self.consume('^') {
|
|
spec.align = AlignCenter;
|
|
}
|
|
// Sign flags
|
|
if self.consume('+') {
|
|
spec.flags |= 1 << (FlagSignPlus as u32);
|
|
} else if self.consume('-') {
|
|
spec.flags |= 1 << (FlagSignMinus as u32);
|
|
}
|
|
// Alternate marker
|
|
if self.consume('#') {
|
|
spec.flags |= 1 << (FlagAlternate as u32);
|
|
}
|
|
// Width and precision
|
|
let mut havewidth = false;
|
|
|
|
if self.consume('0') {
|
|
// small ambiguity with '0$' as a format string. In theory this is a
|
|
// '0' flag and then an ill-formatted format string with just a '$'
|
|
// and no count, but this is better if we instead interpret this as
|
|
// no '0' flag and '0$' as the width instead.
|
|
if self.consume('$') {
|
|
spec.width = CountIsParam(0);
|
|
havewidth = true;
|
|
} else {
|
|
spec.flags |= 1 << (FlagSignAwareZeroPad as u32);
|
|
}
|
|
}
|
|
if !havewidth {
|
|
let width_span_start = if let Some((pos, _)) = self.cur.peek() { *pos } else { 0 };
|
|
let (w, sp) = self.count(width_span_start);
|
|
spec.width = w;
|
|
spec.width_span = sp;
|
|
}
|
|
if let Some(start) = self.consume_pos('.') {
|
|
if let Some(end) = self.consume_pos('*') {
|
|
// Resolve `CountIsNextParam`.
|
|
// We can do this immediately as `position` is resolved later.
|
|
let i = self.curarg;
|
|
self.curarg += 1;
|
|
spec.precision = CountIsParam(i);
|
|
spec.precision_span =
|
|
Some(self.to_span_index(start).to(self.to_span_index(end + 1)));
|
|
} else {
|
|
let (p, sp) = self.count(start);
|
|
spec.precision = p;
|
|
spec.precision_span = sp;
|
|
}
|
|
}
|
|
let ty_span_start = self.cur.peek().map(|(pos, _)| *pos);
|
|
// Optional radix followed by the actual format specifier
|
|
if self.consume('x') {
|
|
if self.consume('?') {
|
|
spec.flags |= 1 << (FlagDebugLowerHex as u32);
|
|
spec.ty = "?";
|
|
} else {
|
|
spec.ty = "x";
|
|
}
|
|
} else if self.consume('X') {
|
|
if self.consume('?') {
|
|
spec.flags |= 1 << (FlagDebugUpperHex as u32);
|
|
spec.ty = "?";
|
|
} else {
|
|
spec.ty = "X";
|
|
}
|
|
} else if self.consume('?') {
|
|
spec.ty = "?";
|
|
} else {
|
|
spec.ty = self.word();
|
|
let ty_span_end = self.cur.peek().map(|(pos, _)| *pos);
|
|
if !spec.ty.is_empty() {
|
|
spec.ty_span = ty_span_start
|
|
.and_then(|s| ty_span_end.map(|e| (s, e)))
|
|
.map(|(start, end)| self.to_span_index(start).to(self.to_span_index(end)));
|
|
}
|
|
}
|
|
spec
|
|
}
|
|
|
|
/// Parses an inline assembly template modifier at the current position, returning the modifier
|
|
/// in the `ty` field of the `FormatSpec` struct.
|
|
fn inline_asm(&mut self) -> FormatSpec<'a> {
|
|
let mut spec = FormatSpec {
|
|
fill: None,
|
|
align: AlignUnknown,
|
|
flags: 0,
|
|
precision: CountImplied,
|
|
precision_span: None,
|
|
width: CountImplied,
|
|
width_span: None,
|
|
ty: &self.input[..0],
|
|
ty_span: None,
|
|
};
|
|
if !self.consume(':') {
|
|
return spec;
|
|
}
|
|
|
|
let ty_span_start = self.cur.peek().map(|(pos, _)| *pos);
|
|
spec.ty = self.word();
|
|
let ty_span_end = self.cur.peek().map(|(pos, _)| *pos);
|
|
if !spec.ty.is_empty() {
|
|
spec.ty_span = ty_span_start
|
|
.and_then(|s| ty_span_end.map(|e| (s, e)))
|
|
.map(|(start, end)| self.to_span_index(start).to(self.to_span_index(end)));
|
|
}
|
|
|
|
spec
|
|
}
|
|
|
|
/// Parses a `Count` parameter at the current position. This does not check
|
|
/// for 'CountIsNextParam' because that is only used in precision, not
|
|
/// width.
|
|
fn count(&mut self, start: usize) -> (Count, Option<InnerSpan>) {
|
|
if let Some(i) = self.integer() {
|
|
if let Some(end) = self.consume_pos('$') {
|
|
let span = self.to_span_index(start).to(self.to_span_index(end + 1));
|
|
(CountIsParam(i), Some(span))
|
|
} else {
|
|
(CountIs(i), None)
|
|
}
|
|
} else {
|
|
let tmp = self.cur.clone();
|
|
let word = self.word();
|
|
if word.is_empty() {
|
|
self.cur = tmp;
|
|
(CountImplied, None)
|
|
} else if self.consume('$') {
|
|
(CountIsName(Symbol::intern(word)), None)
|
|
} else {
|
|
self.cur = tmp;
|
|
(CountImplied, None)
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Parses a word starting at the current position. A word is the same as
|
|
/// Rust identifier, except that it can't start with `_` character.
|
|
fn word(&mut self) -> &'a str {
|
|
let start = match self.cur.peek() {
|
|
Some(&(pos, c)) if rustc_lexer::is_id_start(c) => {
|
|
self.cur.next();
|
|
pos
|
|
}
|
|
_ => {
|
|
return "";
|
|
}
|
|
};
|
|
let mut end = None;
|
|
while let Some(&(pos, c)) = self.cur.peek() {
|
|
if rustc_lexer::is_id_continue(c) {
|
|
self.cur.next();
|
|
} else {
|
|
end = Some(pos);
|
|
break;
|
|
}
|
|
}
|
|
let end = end.unwrap_or(self.input.len());
|
|
let word = &self.input[start..end];
|
|
if word == "_" {
|
|
self.err_with_note(
|
|
"invalid argument name `_`",
|
|
"invalid argument name",
|
|
"argument name cannot be a single underscore",
|
|
self.to_span_index(start).to(self.to_span_index(end)),
|
|
);
|
|
}
|
|
word
|
|
}
|
|
|
|
/// Optionally parses an integer at the current position. This doesn't deal
|
|
/// with overflow at all, it's just accumulating digits.
|
|
fn integer(&mut self) -> Option<usize> {
|
|
let mut cur = 0;
|
|
let mut found = false;
|
|
while let Some(&(_, c)) = self.cur.peek() {
|
|
if let Some(i) = c.to_digit(10) {
|
|
cur = cur * 10 + i as usize;
|
|
found = true;
|
|
self.cur.next();
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
found.then_some(cur)
|
|
}
|
|
}
|
|
|
|
/// Finds the indices of all characters that have been processed and differ between the actual
|
|
/// written code (code snippet) and the `InternedString` that gets processed in the `Parser`
|
|
/// in order to properly synthethise the intra-string `Span`s for error diagnostics.
|
|
fn find_skips_from_snippet(
|
|
snippet: Option<string::String>,
|
|
str_style: Option<usize>,
|
|
) -> (Vec<usize>, bool) {
|
|
let snippet = match snippet {
|
|
Some(ref s) if s.starts_with('"') || s.starts_with("r\"") || s.starts_with("r#") => s,
|
|
_ => return (vec![], false),
|
|
};
|
|
|
|
fn find_skips(snippet: &str, is_raw: bool) -> Vec<usize> {
|
|
let mut s = snippet.char_indices().peekable();
|
|
let mut skips = vec![];
|
|
while let Some((pos, c)) = s.next() {
|
|
match (c, s.peek()) {
|
|
// skip whitespace and empty lines ending in '\\'
|
|
('\\', Some((next_pos, '\n'))) if !is_raw => {
|
|
skips.push(pos);
|
|
skips.push(*next_pos);
|
|
let _ = s.next();
|
|
|
|
while let Some((pos, c)) = s.peek() {
|
|
if matches!(c, ' ' | '\n' | '\t') {
|
|
skips.push(*pos);
|
|
let _ = s.next();
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
('\\', Some((next_pos, 'n' | 't' | 'r' | '0' | '\\' | '\'' | '\"'))) => {
|
|
skips.push(*next_pos);
|
|
let _ = s.next();
|
|
}
|
|
('\\', Some((_, 'x'))) if !is_raw => {
|
|
for _ in 0..3 {
|
|
// consume `\xAB` literal
|
|
if let Some((pos, _)) = s.next() {
|
|
skips.push(pos);
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
('\\', Some((_, 'u'))) if !is_raw => {
|
|
if let Some((pos, _)) = s.next() {
|
|
skips.push(pos);
|
|
}
|
|
if let Some((next_pos, next_c)) = s.next() {
|
|
if next_c == '{' {
|
|
skips.push(next_pos);
|
|
let mut i = 0; // consume up to 6 hexanumeric chars + closing `}`
|
|
while let (Some((next_pos, c)), true) = (s.next(), i < 7) {
|
|
if c.is_digit(16) {
|
|
skips.push(next_pos);
|
|
} else if c == '}' {
|
|
skips.push(next_pos);
|
|
break;
|
|
} else {
|
|
break;
|
|
}
|
|
i += 1;
|
|
}
|
|
} else if next_c.is_digit(16) {
|
|
skips.push(next_pos);
|
|
// We suggest adding `{` and `}` when appropriate, accept it here as if
|
|
// it were correct
|
|
let mut i = 0; // consume up to 6 hexanumeric chars
|
|
while let (Some((next_pos, c)), _) = (s.next(), i < 6) {
|
|
if c.is_digit(16) {
|
|
skips.push(next_pos);
|
|
} else {
|
|
break;
|
|
}
|
|
i += 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
skips
|
|
}
|
|
|
|
let r_start = str_style.map_or(0, |r| r + 1);
|
|
let r_end = str_style.unwrap_or(0);
|
|
let s = &snippet[r_start + 1..snippet.len() - r_end - 1];
|
|
(find_skips(s, str_style.is_some()), true)
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests;
|