Method parse_match_pattern_lhs

crates/ruff_python_parser/src/parser/pattern.rs:142–174

Parses a pattern. See:

(&mut self, allow_star_pattern: AllowStarPattern)

    ///
    /// See: <https://docs.python.org/3/reference/compound_stmts.html#grammar-token-python-grammar-closed_pattern>
    fn parse_match_pattern_lhs(&mut self, allow_star_pattern: AllowStarPattern) -> Pattern {
        self.with_recursion(|parser| {
            let start = parser.node_start();

            let mut lhs = match parser.current_token_kind() {
                TokenKind::Lbrace => Pattern::MatchMapping(parser.parse_match_pattern_mapping()),
                TokenKind::Star => {
                    let star_pattern = parser.parse_match_pattern_star();
                    if allow_star_pattern.is_no() {
                        parser.add_error(ParseErrorType::InvalidStarPatternUsage, &star_pattern);
                    }
                    Pattern::MatchStar(star_pattern)
                }
                TokenKind::Lpar | TokenKind::Lsqb => {
                    parser.parse_parenthesized_or_sequence_pattern()
                }
                _ => parser.parse_match_pattern_literal(),
            };

            if parser.at(TokenKind::Lpar) {
                lhs = Pattern::MatchClass(parser.parse_match_pattern_class(lhs, start));
            }

            if matches!(
                parser.current_token_kind(),
                TokenKind::Plus | TokenKind::Minus
            ) {
                lhs = Pattern::MatchValue(parser.parse_complex_literal_pattern(lhs, start));
            }

            lhs
        })
    }

    /// Parses a mapping pattern.
    ///