boa_engine 0.17.0

Boa is a Javascript lexer, parser and compiler written in Rust. Currently, it has support for some of the language.
Documentation 
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use crate::{bytecompiler::ByteCompiler, vm::Opcode};
use boa_ast::statement::Continue;

impl ByteCompiler<'_, '_> {
    #[allow(clippy::unnecessary_wraps)]
    pub(crate) fn compile_continue(&mut self, node: Continue, _use_expr: bool) {
        if let Some(info) = self.jump_info.last().filter(|info| info.is_try_block()) {
            let in_finally = info.in_finally();
            let in_finally_or_has_finally = in_finally || info.has_finally();

            // 1. Handle if node has a label.
            if let Some(node_label) = node.label() {
                let items = self.jump_info.iter().rev().filter(|info| info.is_loop());
                let mut iterator_closes = Vec::new();

                for info in items {
                    if info.label() == Some(node_label) {
                        break;
                    }

                    if info.iterator_loop() {
                        iterator_closes.push(info.for_await_of_loop());
                    }
                }

                for r#async in iterator_closes {
                    self.iterator_close(r#async);
                }

                let (cont_label, set_label) = self.emit_opcode_with_two_operands(Opcode::Continue);

                let loops = self
                    .jump_info
                    .iter_mut()
                    .rev()
                    .filter(|info| info.is_loop());
                let mut set_continue_as_break = false;
                for info in loops {
                    let found_label = info.label() == Some(node_label);
                    if found_label && in_finally_or_has_finally {
                        set_continue_as_break = true;
                        info.push_try_continue_label(set_label);
                        break;
                    } else if found_label && !in_finally_or_has_finally {
                        info.push_try_continue_label(cont_label);
                        info.push_try_continue_label(set_label);
                        break;
                    }
                }
                if set_continue_as_break {
                    self.jump_info
                        .last_mut()
                        .expect("no jump information found")
                        .push_break_label(cont_label);
                }
            } else {
                // TODO: Add has finally or in finally here
                let (cont_label, set_label) = self.emit_opcode_with_two_operands(Opcode::Continue);
                if in_finally_or_has_finally {
                    self.jump_info
                        .last_mut()
                        .expect("Must exist and be a try block")
                        .push_break_label(cont_label);
                };
                let mut items = self
                    .jump_info
                    .iter_mut()
                    .rev()
                    .filter(|info| info.is_loop());
                let jump_info = items.next().expect("continue must be inside loop");
                if !in_finally_or_has_finally {
                    jump_info.push_try_continue_label(cont_label);
                };
                jump_info.push_try_continue_label(set_label);
            };
        } else if let Some(node_label) = node.label() {
            let items = self.jump_info.iter().rev().filter(|info| info.is_loop());
            let mut iterator_closes = Vec::new();
            for info in items {
                if info.label() == Some(node_label) {
                    break;
                }

                if info.iterator_loop() {
                    iterator_closes.push(info.for_await_of_loop());
                }
            }

            for r#async in iterator_closes {
                self.iterator_close(r#async);
            }

            let (cont_label, set_label) = self.emit_opcode_with_two_operands(Opcode::Continue);
            let loops = self
                .jump_info
                .iter_mut()
                .rev()
                .filter(|info| info.is_loop());

            for info in loops {
                if info.label() == Some(node_label) {
                    info.push_try_continue_label(cont_label);
                    info.push_try_continue_label(set_label);
                }
            }
        } else {
            let (cont_label, set_label) = self.emit_opcode_with_two_operands(Opcode::Continue);
            let mut items = self
                .jump_info
                .iter_mut()
                .rev()
                .filter(|info| info.is_loop());
            let jump_info = items.next().expect("continue must be inside loop");
            jump_info.push_try_continue_label(cont_label);
            jump_info.push_try_continue_label(set_label);
        }
    }
}