Method parse_yield_expression

crates/ruff_python_parser/src/parser/expression.rs:2833–2873

Parses a `yield` expression. # Panics If the parser isn't positioned at a `yield` token. See:

(&mut self)

    ///
    /// See: <https://docs.python.org/3/reference/expressions.html#yield-expressions>
    fn parse_yield_expression(&mut self) -> Expr {
        let start = self.node_start();
        self.bump(TokenKind::Yield);

        if self.eat(TokenKind::From) {
            return self.parse_yield_from_expression(start);
        }

        let value = self.at_expr().then(|| {
            let parsed_expr = self.parse_expression_list(ExpressionContext::starred_bitwise_or());

            // test_ok iter_unpack_yield_py37
            // # parse_options: {"target-version": "3.7"}
            // rest = (4, 5, 6)
            // def g(): yield (1, 2, 3, *rest)

            // test_ok iter_unpack_yield_py38
            // # parse_options: {"target-version": "3.8"}
            // rest = (4, 5, 6)
            // def g(): yield 1, 2, 3, *rest
            // def h(): yield 1, (yield 2, *rest), 3

            // test_err iter_unpack_yield_py37
            // # parse_options: {"target-version": "3.7"}
            // rest = (4, 5, 6)
            // def g(): yield 1, 2, 3, *rest
            // def h(): yield 1, (yield 2, *rest), 3
            self.check_tuple_unpacking(
                &parsed_expr,
                UnsupportedSyntaxErrorKind::StarTuple(StarTupleKind::Yield),
            );

            Box::new(parsed_expr.expr)
        });

        Expr::Yield(ast::ExprYield {
            value,
            range: self.node_range(start),
            node_index: AtomicNodeIndex::NONE,
        })
    }

    /// Parses a `yield from` expression.
    ///