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use crate::{Node, Parser, Token};
pub fn parse_file(p: &mut Parser) {
p.start_node(Node::File);
p.skip_insignificant();
while p.peek().is_some() {
parse_object(p);
}
p.finish_node();
}
pub fn parse_object(p: &mut Parser) {
p.start_node(Node::Object);
p.token(Token::Object);
p.token(Token::LiteralString);
p.token(Token::BraceOpen);
// Parse `code { ... }`
p.start_node(Node::Code);
p.token(Token::Code);
parse_block(p);
p.finish_node();
// Parse objects and raw data
while p.peek_is_not(Token::BraceClose) {
parse_data(p);
}
p.token(Token::BraceClose);
p.finish_node();
}
pub fn parse_block(p: &mut Parser) {
p.start_node(Node::Block);
p.token(Token::BraceOpen);
while p.peek_is_not(Token::BraceClose) {
parse_statement(p);
}
p.token(Token::BraceClose);
p.finish_node();
}
pub fn parse_data(p: &mut Parser) {
use Token::*;
if let Some(token) = p.peek() {
match token {
Object => parse_object(p),
Data => {
p.start_node(Node::Data);
p.token(Data);
p.token(LiteralString);
if let Some(token) = p.peek() {
match token {
LiteralString => p.token(LiteralString),
LiteralStringHex => p.token(LiteralStringHex),
_ => p.error(),
}
}
p.finish_node();
}
_ => p.error(),
}
}
}
pub fn parse_statement(p: &mut Parser) {
use Token::*;
if let Some(token) = p.peek() {
p.start_node(Node::Statement);
match token {
BraceOpen => parse_block(p),
Function => {
p.start_node(Node::Function);
p.token(Function);
p.token(Identifier);
p.start_node(Node::Arguments);
p.token(ParenOpen);
if p.peek_is(Identifier) {
parse_indentifiers(p);
}
p.token(ParenClose);
p.finish_node();
p.start_node(Node::Returns);
if p.peek_is(Returns) {
p.token(Returns);
parse_indentifiers(p);
}
p.finish_node();
parse_block(p);
p.finish_node();
}
Let => {
p.start_node(Node::Let);
p.token(Let);
parse_indentifiers(p);
if p.peek_is(Assign) {
p.token(Assign);
parse_expression(p);
}
p.finish_node();
}
If => {
p.start_node(Node::If);
p.token(If);
parse_expression(p);
parse_block(p);
p.finish_node();
}
Switch => {
p.start_node(Node::Switch);
p.token(Switch);
parse_expression(p);
while p.peek_is(Case) {
p.start_node(Node::Case);
p.token(Case);
parse_expression(p); // TODO: Only accept literal.
parse_block(p);
p.finish_node();
}
if p.peek_is(Default) {
p.start_node(Node::CaseDefault);
p.token(Default);
parse_block(p);
p.finish_node();
}
p.finish_node();
}
For => {
p.start_node(Node::For);
p.token(For);
parse_block(p);
parse_expression(p);
parse_block(p);
parse_block(p);
p.finish_node();
}
Break => {
p.start_node(Node::Break);
p.token(Break);
p.finish_node();
}
Continue => {
p.start_node(Node::Continue);
p.token(Continue);
p.finish_node();
}
Leave => {
p.start_node(Node::Leave);
p.token(Leave);
p.finish_node();
}
_ => {
// Here the grammar is a bit challenging, we can either have an
// expression or an assignment. Both can start with an identifier.
// If after the first identifier we get a Comma or Assign, we
// know it will be an assignment. Otherwise it will be an expression.
if p.peek_is(Identifier) {
let start = p.checkpoint();
p.token(Identifier);
match p.peek() {
Some(Comma) => {
p.start_node_at(start, Node::Assignment);
p.start_node_at(start, Node::Identifiers);
while p.peek_is(Comma) {
p.token(Comma);
p.token(Identifier);
}
p.finish_node();
p.token(Assign);
parse_expression(p);
p.finish_node();
}
Some(Assign) => {
p.start_node_at(start, Node::Assignment);
p.start_node_at(start, Node::Identifiers);
p.finish_node();
p.token(Assign);
parse_expression(p);
p.finish_node();
}
Some(ParenOpen) => {
// Call Expression
p.start_node_at(start, Node::Expression);
p.start_node_at(start, Node::Call);
p.start_node(Node::Arguments);
p.token(ParenOpen);
while p.peek_is_not(ParenClose) {
parse_expression(p);
if p.peek_is_not(ParenClose) {
p.token(Comma);
}
}
p.token(ParenClose);
p.finish_node();
p.finish_node();
p.finish_node();
}
_ => {
// Identifier Expression
p.start_node_at(start, Node::Expression);
p.finish_node();
}
}
} else {
parse_expression(p);
}
}
}
p.finish_node();
}
}
pub fn parse_expression(p: &mut Parser) {
use Token::*;
if let Some(token) = p.peek() {
p.start_node(Node::Expression);
match token {
Identifier => {
let start = p.checkpoint();
p.token(Identifier);
if p.peek_is(ParenOpen) {
p.start_node_at(start, Node::Call);
p.start_node(Node::Arguments);
p.token(ParenOpen);
while p.peek_is_not(ParenClose) {
parse_expression(p);
if p.peek_is_not(ParenClose) {
p.token(Comma);
}
}
p.token(ParenClose);
p.finish_node();
p.finish_node();
}
}
LiteralTrue | LiteralFalse | LiteralHex | LiteralInt | LiteralString => {
p.start_node(Node::Literal);
p.bump();
p.skip_insignificant();
p.finish_node();
}
_ => p.error(),
}
p.finish_node();
}
}
pub fn parse_indentifiers(p: &mut Parser) {
use Token::*;
p.start_node(Node::Identifiers);
p.token(Identifier);
while p.peek_is(Comma) {
p.token(Comma);
p.token(Identifier);
}
p.finish_node();
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn parse_example() {
let input = include_str!("../test/example.yul");
let mut parser = Parser::new(input);
parse_file(&mut parser);
let parse = parser.finish();
assert_eq!(
format!("{:#?}", &parse),
include_str!("../test/example.parse.txt")
);
let unparse = parse.unparse();
assert_eq!(input, unparse);
}
#[test]
fn parse_erc20() {
let input = include_str!("../test/erc20.yul");
let mut parser = Parser::new(input);
parse_file(&mut parser);
let parse = parser.finish();
assert_eq!(
format!("{:#?}", &parse),
include_str!("../test/erc20.parse.txt")
);
let unparse = parse.unparse();
assert_eq!(input, unparse);
}
}