Method parse_if_statement

crates/ruff_python_parser/src/parser/statement.rs:1423–1475

Parses an `if` statement. # Panics If the parser isn't positioned at an `if` token. See:

(&mut self)

    ///
    /// See: <https://docs.python.org/3/reference/compound_stmts.html#the-if-statement>
    fn parse_if_statement(&mut self) -> ast::StmtIf {
        let start = self.node_start();
        self.bump(TokenKind::If);

        // test_err if_stmt_invalid_test_expr
        // if *x: ...
        // if yield x: ...
        // if yield from x: ...

        // test_err if_stmt_missing_test
        // if : ...
        let test = self.parse_named_expression_or_higher(ExpressionContext::default());

        // test_err if_stmt_missing_colon
        // if x
        // if x
        //     pass
        // a = 1
        self.expect(TokenKind::Colon);

        // test_err if_stmt_empty_body
        // if True:
        // 1 + 1
        let body = self.parse_body(Clause::If);

        // test_err if_stmt_misspelled_elif
        // if True:
        //     pass
        // elf:
        //     pass
        // else:
        //     pass
        let mut elif_else_clauses = self.parse_clauses(Clause::ElIf, |p| {
            p.parse_elif_or_else_clause(ElifOrElse::Elif)
        });

        if self.at(TokenKind::Else) {
            if elif_else_clauses.is_empty() {
                elif_else_clauses.reserve_exact(1);
            }
            elif_else_clauses.push(self.parse_elif_or_else_clause(ElifOrElse::Else));
        }

        elif_else_clauses.shrink_to_fit();

        ast::StmtIf {
            test: Box::new(test.expr),
            body,
            elif_else_clauses,
            range: self.node_range(start),
            node_index: AtomicNodeIndex::NONE,
        }
    }

    /// Parses an `elif` or `else` clause.
    ///