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dust/dust-lang/src/parser.rs

2291 lines
74 KiB
Rust

//! Parsing tools.
//!
//! This module provides two parsing options:
//! - `parse` convenience function
//! - `Parser` struct, which parses the input a statement at a time
use std::{
collections::VecDeque,
fmt::{self, Display, Formatter},
num::{ParseFloatError, ParseIntError},
str::ParseBoolError,
};
use crate::{
ast::*, Context, DustError, Identifier, LexError, Lexer, Token, TokenKind, TokenOwned, Type,
};
/// Parses the input into an abstract syntax tree.
///
/// # Examples
/// ```
/// # use dust_lang::*;
/// let source = "42.to_string()";
///
/// assert_eq!(
/// parse(source),
/// Ok(AbstractSyntaxTree::with_statements([
/// Statement::Expression(Expression::call(
/// Expression::field_access(
/// Expression::literal(42, (0, 2)),
/// Node::new(Identifier::new("to_string"), (3, 12)),
/// (0, 12)
/// ),
/// vec![],
/// (0, 14)
/// ))
/// ]))
/// );
/// ```
pub fn parse(source: &str) -> Result<AbstractSyntaxTree, DustError> {
let mut tree = AbstractSyntaxTree::new();
parse_into(source, &mut tree)?;
Ok(tree)
}
pub fn parse_into<'src>(
source: &'src str,
tree: &mut AbstractSyntaxTree,
) -> Result<(), DustError<'src>> {
let lexer = Lexer::new(source);
let mut parser = Parser::new(lexer);
loop {
let node = parser
.parse_statement()
.map_err(|parse_error| DustError::Parse {
parse_error,
source,
})?;
tree.statements.push_back(node);
if let Token::Eof = parser.current_token {
break;
}
}
Ok(())
}
/// Low-level tool for parsing the input a statement at a time.
///
/// # Examples
/// ```
/// # use std::collections::VecDeque;
/// # use dust_lang::*;
/// let source = "x = 42";
/// let lexer = Lexer::new(source);
/// let mut parser = Parser::new(lexer);
/// let mut statements = VecDeque::new();
///
/// loop {
/// let statement = parser.parse_statement().unwrap();
///
/// statements.push_back(statement);
///
/// if parser.is_eof() {
/// break;
/// }
/// }
///
/// let tree = AbstractSyntaxTree { statements };
///
/// ```
pub struct Parser<'src> {
lexer: Lexer<'src>,
current_token: Token<'src>,
current_position: Span,
mode: ParserMode,
context: Context,
}
impl<'src> Parser<'src> {
pub fn new(mut lexer: Lexer<'src>) -> Self {
let (current_token, current_position) = lexer.next_token().unwrap_or((Token::Eof, (0, 0)));
Parser {
lexer,
current_token,
current_position,
mode: ParserMode::Normal,
context: Context::new(),
}
}
pub fn is_eof(&self) -> bool {
matches!(self.current_token, Token::Eof)
}
pub fn parse_statement(&mut self) -> Result<Statement, ParseError> {
let start_position = self.current_position;
if let Token::Let = self.current_token {
log::trace!("Parsing let statement");
self.next_token()?;
let is_mutable = if let Token::Mut = self.current_token {
self.next_token()?;
true
} else {
false
};
let identifier = self.parse_identifier()?;
if let Token::Equal = self.current_token {
self.next_token()?;
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::Equal,
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
let value = self.parse_expression(0)?;
let end = if let Token::Semicolon = self.current_token {
let end = self.current_position.1;
self.next_token()?;
end
} else {
value.position().1
};
let r#let = if is_mutable {
LetStatement::LetMut { identifier, value }
} else {
LetStatement::Let { identifier, value }
};
let position = (start_position.0, end);
return Ok(Statement::Let(Node::new(r#let, position)));
}
if let Token::Struct = self.current_token {
log::trace!("Parsing struct definition");
self.next_token()?;
let name = if let Token::Identifier(_) = self.current_token {
self.parse_identifier()?
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::Identifier,
actual: self.current_token.to_owned(),
position: self.current_position,
});
};
if let Token::Semicolon = self.current_token {
let end = self.current_position.1;
self.next_token()?;
return Ok(Statement::struct_definition(
StructDefinition::Unit { name },
(start_position.0, end),
));
}
if let Token::LeftParenthesis = self.current_token {
self.next_token()?;
let mut types = Vec::new();
loop {
if let Token::RightParenthesis = self.current_token {
self.next_token()?;
if let Token::Semicolon = self.current_token {
self.next_token()?;
}
break;
}
let type_node = self.parse_type()?;
types.push(type_node);
if let Token::Comma = self.current_token {
self.next_token()?;
continue;
}
}
let position = (start_position.0, self.current_position.1);
return if types.is_empty() {
Ok(Statement::struct_definition(
StructDefinition::Unit { name },
position,
))
} else {
Ok(Statement::struct_definition(
StructDefinition::Tuple { name, items: types },
position,
))
};
}
if let Token::LeftCurlyBrace = self.current_token {
self.next_token()?;
let mut fields = Vec::new();
loop {
if let Token::RightCurlyBrace = self.current_token {
self.next_token()?;
if let Token::Semicolon = self.current_token {
self.next_token()?;
}
break;
}
let field_name = self.parse_identifier()?;
if let Token::Colon = self.current_token {
self.next_token()?;
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::Colon,
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
let field_type = self.parse_type()?;
fields.push((field_name, field_type));
if let Token::Comma = self.current_token {
self.next_token()?;
continue;
}
}
let position = (start_position.0, self.current_position.1);
return if fields.is_empty() {
Ok(Statement::struct_definition(
StructDefinition::Unit { name },
position,
))
} else {
Ok(Statement::struct_definition(
StructDefinition::Fields { name, fields },
position,
))
};
}
return Err(ParseError::ExpectedTokenMultiple {
expected: vec![
TokenKind::LeftParenthesis,
TokenKind::LeftCurlyBrace,
TokenKind::Semicolon,
],
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
let expression = self.parse_expression(0)?;
if let Token::Semicolon = self.current_token {
let position = (start_position.0, self.current_position.1);
self.next_token()?;
Ok(Statement::ExpressionNullified(Node::new(
expression, position,
)))
} else {
Ok(Statement::Expression(expression))
}
}
fn next_token(&mut self) -> Result<(), ParseError> {
let (token, position) = self.lexer.next_token()?;
self.current_token = token;
self.current_position = position;
Ok(())
}
fn parse_expression(&mut self, mut precedence: u8) -> Result<Expression, ParseError> {
// Parse a statement starting from the current node.
let mut left = if self.current_token.is_prefix() {
self.parse_prefix()?
} else {
self.parse_primary()?
};
// While the current token has a higher precedence than the given precedence
while precedence < self.current_token.precedence() {
// Give precedence to postfix operations
left = if self.current_token.is_postfix() {
let statement = self.parse_postfix(left)?;
precedence = self.current_token.precedence();
// Replace the left-hand side with the postfix operation
statement
} else {
// Replace the left-hand side with the infix operation
self.parse_infix(left)?
};
}
Ok(left)
}
fn parse_prefix(&mut self) -> Result<Expression, ParseError> {
log::trace!("Parsing {} as prefix operator", self.current_token);
let operator_start = self.current_position.0;
match self.current_token {
Token::Bang => {
self.next_token()?;
let operand = self.parse_expression(0)?;
let position = (operator_start, self.current_position.1);
Ok(Expression::not(operand, position))
}
Token::Minus => {
self.next_token()?;
let operand = self.parse_expression(0)?;
let position = (operator_start, self.current_position.1);
Ok(Expression::negation(operand, position))
}
Token::Star => {
self.next_token()?;
let operand = self.parse_expression(0)?;
let position = (operator_start, self.current_position.1);
Ok(Expression::dereference(operand, position))
}
_ => Err(ParseError::ExpectedTokenMultiple {
expected: vec![TokenKind::Bang, TokenKind::Minus, TokenKind::Star],
actual: self.current_token.to_owned(),
position: self.current_position,
}),
}
}
fn parse_primary(&mut self) -> Result<Expression, ParseError> {
log::trace!("Parsing {} as primary", self.current_token);
let start_position = self.current_position;
match self.current_token {
Token::Async => {
let block = self.parse_block()?;
let position = (start_position.0, block.position.1);
Ok(Expression::block(block.inner, position))
}
Token::Boolean(text) => {
self.next_token()?;
let boolean = text.parse::<bool>().map_err(|error| ParseError::Boolean {
error,
position: start_position,
})?;
let expression = Expression::literal(boolean, start_position);
Ok(expression)
}
Token::Break => {
let break_end = self.current_position.1;
self.next_token()?;
let (expression_option, end) = if let Token::Semicolon = self.current_token {
// Do not consume the semicolon, allowing it to nullify the expression
(None, break_end)
} else if let Ok(expression) = self.parse_expression(0) {
let end = expression.position().1;
(Some(expression), end)
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::Semicolon,
actual: self.current_token.to_owned(),
position: self.current_position,
});
};
let position = (start_position.0, end);
Ok(Expression::r#break(expression_option, position))
}
Token::Character(character) => {
self.next_token()?;
let expression = Expression::literal(character, start_position);
Ok(expression)
}
Token::Float(text) => {
self.next_token()?;
let float = text.parse::<f64>().map_err(|error| ParseError::Float {
error,
position: start_position,
})?;
Ok(Expression::literal(float, start_position))
}
Token::Identifier(text) => {
self.next_token()?;
let identifier = Identifier::new(text);
if let ParserMode::Condition = self.mode {
return Ok(Expression::identifier(identifier, start_position));
}
if let Token::LeftCurlyBrace = self.current_token {
self.next_token()?;
let name = Node::new(identifier, start_position);
let mut fields = Vec::new();
loop {
if let Token::RightCurlyBrace = self.current_token {
self.next_token()?;
break;
}
let field_name = self.parse_identifier()?;
if let Token::Colon = self.current_token {
self.next_token()?;
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::Colon,
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
let field_value = self.parse_expression(0)?;
fields.push((field_name, field_value));
if let Token::Comma = self.current_token {
self.next_token()?;
}
}
let position = (start_position.0, self.current_position.1);
return Ok(Expression::r#struct(
StructExpression::Fields { name, fields },
position,
));
}
Ok(Expression::identifier(identifier, start_position))
}
Token::Integer(text) => {
self.next_token()?;
let integer = text.parse::<i64>().map_err(|error| ParseError::Integer {
error,
position: start_position,
})?;
Ok(Expression::literal(integer, start_position))
}
Token::If => {
self.next_token()?;
let r#if = self.parse_if()?;
let position = (start_position.0, self.current_position.1);
Ok(Expression::r#if(r#if, position))
}
Token::String(text) => {
self.next_token()?;
Ok(Expression::literal(text.to_string(), start_position))
}
Token::LeftCurlyBrace => {
let block_node = self.parse_block()?;
Ok(Expression::block(block_node.inner, block_node.position))
}
Token::LeftParenthesis => {
self.next_token()?;
let node = self.parse_expression(0)?;
if let Token::RightParenthesis = self.current_token {
let position = (start_position.0, self.current_position.1);
self.next_token()?;
Ok(Expression::grouped(node, position))
} else {
Err(ParseError::ExpectedToken {
expected: TokenKind::RightParenthesis,
actual: self.current_token.to_owned(),
position: self.current_position,
})
}
}
Token::LeftSquareBrace => {
self.next_token()?;
if let Token::RightSquareBrace = self.current_token {
let position = (start_position.0, self.current_position.1);
self.next_token()?;
return Ok(Expression::list(Vec::new(), position));
}
let first_expression = self.parse_expression(0)?;
if let Token::Semicolon = self.current_token {
self.next_token()?;
let repeat_operand = self.parse_expression(0)?;
if let Token::RightSquareBrace = self.current_token {
let position = (start_position.0, self.current_position.1);
self.next_token()?;
return Ok(Expression::auto_fill_list(
first_expression,
repeat_operand,
position,
));
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::RightSquareBrace,
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
}
let mut expressions = vec![first_expression];
loop {
if let Token::RightSquareBrace = self.current_token {
let position = (start_position.0, self.current_position.1);
self.next_token()?;
return Ok(Expression::list(expressions, position));
}
if let Token::Comma = self.current_token {
self.next_token()?;
continue;
}
let expression = self.parse_expression(0)?;
expressions.push(expression);
}
}
Token::Loop => {
self.next_token()?;
let block = self.parse_block()?;
let position = (start_position.0, block.position.1);
Ok(Expression::infinite_loop(block, position))
}
Token::Map => {
self.next_token()?;
if let Token::LeftCurlyBrace = self.current_token {
self.next_token()?;
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::LeftCurlyBrace,
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
let mut fields = Vec::new();
loop {
if let Token::RightCurlyBrace = self.current_token {
let position = (start_position.0, self.current_position.1);
self.next_token()?;
return Ok(Expression::map(fields, position));
}
let field_name = self.parse_identifier()?;
if let Token::Equal = self.current_token {
self.next_token()?;
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::Equal,
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
let field_value = self.parse_expression(0)?;
fields.push((field_name, field_value));
if let Token::Comma = self.current_token {
self.next_token()?;
}
}
}
Token::While => {
self.next_token()?;
let condition = self.parse_expression(0)?;
let block = self.parse_block()?;
let position = (start_position.0, block.position.1);
Ok(Expression::while_loop(condition, block, position))
}
_ => Err(ParseError::ExpectedTokenMultiple {
expected: vec![
TokenKind::Async,
TokenKind::Boolean,
TokenKind::Float,
TokenKind::Identifier,
TokenKind::Integer,
TokenKind::If,
TokenKind::LeftCurlyBrace,
TokenKind::LeftParenthesis,
TokenKind::LeftSquareBrace,
TokenKind::String,
TokenKind::While,
],
actual: self.current_token.to_owned(),
position: self.current_position,
}),
}
}
fn parse_infix(&mut self, left: Expression) -> Result<Expression, ParseError> {
log::trace!("Parsing {} as infix operator", self.current_token);
let operator_precedence = self.current_token.precedence()
- if self.current_token.is_right_associative() {
1
} else {
0
};
let left_start = left.position().0;
if let Token::Equal = &self.current_token {
self.next_token()?;
let value = self.parse_expression(operator_precedence)?;
let position = (left_start, value.position().1);
return Ok(Expression::assignment(left, value, position));
}
if let Token::PlusEqual | Token::MinusEqual = &self.current_token {
let math_operator = match self.current_token {
Token::PlusEqual => MathOperator::Add,
Token::MinusEqual => MathOperator::Subtract,
_ => unreachable!(),
};
let operator = Node::new(math_operator, self.current_position);
self.next_token()?;
let value = self.parse_expression(operator_precedence)?;
let position = (left_start, value.position().1);
return Ok(Expression::operator(
OperatorExpression::CompoundAssignment {
assignee: left,
operator,
modifier: value,
},
position,
));
}
if let Token::DoubleDot = &self.current_token {
self.next_token()?;
let end = self.parse_expression(operator_precedence)?;
let position = (left_start, end.position().1);
return Ok(Expression::exclusive_range(left, end, position));
}
if let Token::Minus | Token::Plus | Token::Star | Token::Slash | Token::Percent =
&self.current_token
{
let math_operator = match &self.current_token {
Token::Minus => Node::new(MathOperator::Subtract, self.current_position),
Token::Plus => Node::new(MathOperator::Add, self.current_position),
Token::Star => Node::new(MathOperator::Multiply, self.current_position),
Token::Slash => Node::new(MathOperator::Divide, self.current_position),
Token::Percent => Node::new(MathOperator::Modulo, self.current_position),
_ => unreachable!(),
};
self.next_token()?;
let right = self.parse_expression(operator_precedence)?;
let position = (left_start, right.position().1);
return Ok(Expression::operator(
OperatorExpression::Math {
left,
operator: math_operator,
right,
},
position,
));
}
if let Token::DoubleEqual
| Token::BangEqual
| Token::Less
| Token::LessEqual
| Token::Greater
| Token::GreaterEqual = &self.current_token
{
let comparison_operator = match &self.current_token {
Token::DoubleEqual => Node::new(ComparisonOperator::Equal, self.current_position),
Token::BangEqual => Node::new(ComparisonOperator::NotEqual, self.current_position),
Token::Less => Node::new(ComparisonOperator::LessThan, self.current_position),
Token::LessEqual => {
Node::new(ComparisonOperator::LessThanOrEqual, self.current_position)
}
Token::Greater => Node::new(ComparisonOperator::GreaterThan, self.current_position),
Token::GreaterEqual => Node::new(
ComparisonOperator::GreaterThanOrEqual,
self.current_position,
),
_ => unreachable!(),
};
self.next_token()?;
let right = self.parse_expression(operator_precedence)?;
let position = (left_start, right.position().1);
return Ok(Expression::operator(
OperatorExpression::Comparison {
left,
operator: comparison_operator,
right,
},
position,
));
}
let logic_operator = match &self.current_token {
Token::DoubleAmpersand => Node::new(LogicOperator::And, self.current_position),
Token::DoublePipe => Node::new(LogicOperator::Or, self.current_position),
_ => {
return Err(ParseError::UnexpectedToken {
actual: self.current_token.to_owned(),
position: self.current_position,
})
}
};
self.next_token()?;
let right = self.parse_expression(operator_precedence)?;
let position = (left_start, right.position().1);
Ok(Expression::operator(
OperatorExpression::Logic {
left,
operator: logic_operator,
right,
},
position,
))
}
fn parse_postfix(&mut self, left: Expression) -> Result<Expression, ParseError> {
log::trace!("Parsing {} as postfix operator", self.current_token);
let expression = match &self.current_token {
Token::Dot => {
self.next_token()?;
if let Token::Integer(text) = &self.current_token {
let index = text.parse::<usize>().map_err(|error| ParseError::Integer {
error,
position: self.current_position,
})?;
let index_node = Node::new(index, self.current_position);
let position = (left.position().0, self.current_position.1);
self.next_token()?;
Expression::tuple_access(left, index_node, position)
} else {
let field = self.parse_identifier()?;
let position = (left.position().0, field.position.1);
Expression::field_access(left, field, position)
}
}
Token::LeftParenthesis => {
self.next_token()?;
let mut arguments = Vec::new();
while self.current_token != Token::RightParenthesis {
let argument = self.parse_expression(0)?;
arguments.push(argument);
if let Token::Comma = self.current_token {
self.next_token()?;
} else {
break;
}
}
self.next_token()?;
let position = (left.position().0, self.current_position.1);
Expression::call(left, arguments, position)
}
Token::LeftSquareBrace => {
self.next_token()?;
let index = self.parse_expression(0)?;
let operator_end = if let Token::RightSquareBrace = self.current_token {
let end = self.current_position.1;
self.next_token()?;
end
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::RightSquareBrace,
actual: self.current_token.to_owned(),
position: self.current_position,
});
};
let position = (left.position().0, operator_end);
Expression::list_index(left, index, position)
}
_ => {
return Err(ParseError::ExpectedTokenMultiple {
expected: vec![
TokenKind::Dot,
TokenKind::LeftParenthesis,
TokenKind::LeftSquareBrace,
],
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
};
if self.current_token.is_postfix() {
self.parse_postfix(expression)
} else {
Ok(expression)
}
}
fn parse_if(&mut self) -> Result<IfExpression, ParseError> {
// Assume that the "if" token has already been consumed
self.mode = ParserMode::Condition;
let condition = self.parse_expression(0)?;
self.mode = ParserMode::Normal;
let if_block = self.parse_block()?;
if let Token::Else = self.current_token {
self.next_token()?;
let if_keyword_start = self.current_position.0;
if let Token::If = self.current_token {
self.next_token()?;
let if_expression = self.parse_if()?;
let position = (if_keyword_start, self.current_position.1);
Ok(IfExpression::IfElse {
condition,
if_block,
r#else: ElseExpression::If(Node::new(Box::new(if_expression), position)),
})
} else {
let else_block = self.parse_block()?;
Ok(IfExpression::IfElse {
condition,
if_block,
r#else: ElseExpression::Block(else_block),
})
}
} else {
Ok(IfExpression::If {
condition,
if_block,
})
}
}
fn parse_identifier(&mut self) -> Result<Node<Identifier>, ParseError> {
if let Token::Identifier(text) = self.current_token {
let position = self.current_position;
self.next_token()?;
Ok(Node::new(Identifier::new(text), position))
} else {
Err(ParseError::ExpectedToken {
expected: TokenKind::Identifier,
actual: self.current_token.to_owned(),
position: self.current_position,
})
}
}
fn parse_block(&mut self) -> Result<Node<BlockExpression>, ParseError> {
let left_start = self.current_position.0;
let is_async = if let Token::Async = self.current_token {
self.next_token()?;
true
} else {
false
};
if let Token::LeftCurlyBrace = self.current_token {
self.next_token()?;
} else {
return Err(ParseError::ExpectedToken {
expected: TokenKind::LeftCurlyBrace,
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
let mut statements = VecDeque::new();
loop {
if let Token::RightCurlyBrace = self.current_token {
let position = (left_start, self.current_position.1);
self.next_token()?;
let ast = AbstractSyntaxTree {
statements,
context: self.context.create_child(),
};
return if is_async {
Ok(Node::new(BlockExpression::Async(ast), position))
} else {
Ok(Node::new(BlockExpression::Sync(ast), position))
};
}
let statement = self.parse_statement()?;
statements.push_back(statement);
}
}
fn parse_type(&mut self) -> Result<Node<Type>, ParseError> {
let r#type = match self.current_token {
Token::Bool => Type::Boolean,
Token::FloatKeyword => Type::Float,
Token::Int => Type::Integer,
_ => {
return Err(ParseError::ExpectedTokenMultiple {
expected: vec![TokenKind::Bool, TokenKind::FloatKeyword, TokenKind::Int],
actual: self.current_token.to_owned(),
position: self.current_position,
});
}
};
let position = self.current_position;
self.next_token()?;
Ok(Node::new(r#type, position))
}
}
#[derive(Debug, PartialEq, Clone)]
pub enum ParserMode {
Condition,
Normal,
}
#[derive(Debug, PartialEq, Clone)]
pub enum ParseError {
Boolean {
error: ParseBoolError,
position: Span,
},
Lex(LexError),
ExpectedAssignment {
actual: Statement,
},
ExpectedExpression {
actual: Statement,
},
ExpectedIdentifierNode {
actual: Expression,
},
ExpectedIdentifierToken {
actual: TokenOwned,
position: Span,
},
ExpectedToken {
expected: TokenKind,
actual: TokenOwned,
position: Span,
},
ExpectedTokenMultiple {
expected: Vec<TokenKind>,
actual: TokenOwned,
position: Span,
},
UnexpectedToken {
actual: TokenOwned,
position: Span,
},
Float {
error: ParseFloatError,
position: Span,
},
Integer {
error: ParseIntError,
position: Span,
},
}
impl From<LexError> for ParseError {
fn from(v: LexError) -> Self {
Self::Lex(v)
}
}
impl ParseError {
pub fn position(&self) -> Span {
match self {
ParseError::Boolean { position, .. } => *position,
ParseError::ExpectedAssignment { actual } => actual.position(),
ParseError::ExpectedExpression { actual } => actual.position(),
ParseError::ExpectedIdentifierNode { actual } => actual.position(),
ParseError::ExpectedIdentifierToken { position, .. } => *position,
ParseError::ExpectedToken { position, .. } => *position,
ParseError::ExpectedTokenMultiple { position, .. } => *position,
ParseError::Float { position, .. } => *position,
ParseError::Integer { position, .. } => *position,
ParseError::Lex(error) => error.position(),
ParseError::UnexpectedToken { position, .. } => *position,
}
}
}
impl Display for ParseError {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
match self {
Self::Boolean { error, .. } => write!(f, "{}", error),
Self::ExpectedAssignment { .. } => write!(f, "Expected assignment"),
Self::ExpectedExpression { .. } => write!(f, "Expected expression"),
Self::ExpectedIdentifierNode { actual } => {
write!(f, "Expected identifier, found {actual}")
}
Self::ExpectedIdentifierToken { actual, .. } => {
write!(f, "Expected identifier, found {actual}")
}
Self::ExpectedToken {
expected, actual, ..
} => write!(f, "Expected token {expected}, found {actual}"),
Self::ExpectedTokenMultiple {
expected, actual, ..
} => {
write!(f, "Expected one of")?;
for (i, token_kind) in expected.iter().enumerate() {
if i == 0 {
write!(f, " {token_kind}")?;
} else if i == expected.len() - 1 {
write!(f, " or {token_kind}")?;
} else {
write!(f, ", {token_kind}")?;
}
}
write!(f, ", found {actual}")
}
Self::Float { error, .. } => write!(f, "{}", error),
Self::Integer { error, .. } => write!(f, "{}", error),
Self::Lex(error) => write!(f, "{}", error),
Self::UnexpectedToken { actual, .. } => write!(f, "Unexpected token {actual}"),
}
}
}
#[cfg(test)]
mod tests {
use crate::{Identifier, Type};
use super::*;
#[test]
fn dereference() {
let source = "*a";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::dereference(
Expression::identifier(Identifier::new("a"), (1, 2)),
(0, 2)
),)
]))
);
}
#[test]
fn character_literal() {
let source = "'a'";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::literal('a', (0, 3)))
]))
);
}
#[test]
fn break_loop() {
let source = "loop { break; }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::infinite_loop(
Node::new(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::ExpressionNullified(Node::new(
Expression::r#break(None, (7, 12)),
(7, 13)
))
])),
(5, 15)
),
(0, 15)
))
]))
);
}
#[test]
fn built_in_function() {
let source = "42.to_string()";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::call(
Expression::field_access(
Expression::literal(42, (0, 2)),
Node::new(Identifier::new("to_string"), (3, 12)),
(0, 12)
),
vec![],
(0, 14)
))
]))
);
}
#[test]
fn map_expression() {
let source = "map { x = \"1\", y = 2, z = 3.0 }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::map(
vec![
(
Node::new(Identifier::new("x"), (6, 7)),
Expression::literal("1".to_string(), (10, 13)),
),
(
Node::new(Identifier::new("y"), (15, 16)),
Expression::literal(2, (19, 20)),
),
(
Node::new(Identifier::new("z"), (22, 23)),
Expression::literal(3.0, (26, 29)),
),
],
(0, 31),
))
]))
);
}
#[test]
fn let_mut_while_loop() {
let source = "let mut x = 0; while x < 10 { x += 1 }; x";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Let(Node::new(
LetStatement::LetMut {
identifier: Node::new(Identifier::new("x"), (8, 9)),
value: Expression::literal(0, (12, 13)),
},
(0, 14),
)),
Statement::ExpressionNullified(Node::new(
Expression::while_loop(
Expression::comparison(
Expression::identifier(Identifier::new("x"), (21, 22)),
Node::new(ComparisonOperator::LessThan, (23, 24)),
Expression::literal(10, (25, 27)),
(21, 27),
),
Node::new(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::compound_assignment(
Expression::identifier(Identifier::new("x"), (30, 31)),
Node::new(MathOperator::Add, (32, 34)),
Expression::literal(1, (35, 36)),
(30, 36),
),)
])),
(28, 38),
),
(15, 38),
),
(15, 39)
)),
Statement::Expression(Expression::identifier(Identifier::new("x"), (40, 41)),),
]))
);
}
#[test]
fn let_statement() {
let source = "let x = 42;";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([Statement::Let(
Node::new(
LetStatement::Let {
identifier: Node::new(Identifier::new("x"), (4, 5)),
value: Expression::literal(42, (8, 10)),
},
(0, 11),
)
)]))
);
}
#[test]
fn let_mut_statement() {
let source = "let mut x = false;";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([Statement::Let(
Node::new(
LetStatement::LetMut {
identifier: Node::new(Identifier::new("x"), (8, 9)),
value: Expression::literal(false, (12, 17)),
},
(0, 18),
)
)]))
);
}
#[test]
fn async_block() {
let source = "async { x = 42; y = 4.0 }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::block(
BlockExpression::Async(AbstractSyntaxTree::with_statements([
Statement::ExpressionNullified(Node::new(
Expression::operator(
OperatorExpression::Assignment {
assignee: Expression::identifier(Identifier::new("x"), (8, 9)),
value: Expression::literal(42, (12, 14)),
},
(8, 14)
),
(8, 15)
)),
Statement::Expression(Expression::operator(
OperatorExpression::Assignment {
assignee: Expression::identifier(Identifier::new("y"), (16, 17)),
value: Expression::literal(4.0, (20, 23)),
},
(16, 23)
))
])),
(0, 25)
))
]))
);
}
#[test]
fn tuple_struct_access() {
let source = "Foo(42, \"bar\").0";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::tuple_access(
Expression::call(
Expression::identifier(Identifier::new("Foo"), (0, 3)),
vec![
Expression::literal(42, (4, 6)),
Expression::literal("bar".to_string(), (8, 13)),
],
(0, 15)
),
Node::new(0, (15, 16)),
(0, 16)
))
]))
);
}
#[test]
fn fields_struct_instantiation() {
let source = "Foo { a: 42, b: 4.0 }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::r#struct(
StructExpression::Fields {
name: Node::new(Identifier::new("Foo"), (0, 3)),
fields: vec![
(
Node::new(Identifier::new("a"), (6, 7)),
Expression::literal(42, (9, 11)),
),
(
Node::new(Identifier::new("b"), (13, 14)),
Expression::literal(4.0, (16, 19))
)
]
},
(0, 21)
))
]))
);
}
#[test]
fn fields_struct() {
let source = "struct Foo { a: int, b: float }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::struct_definition(
StructDefinition::Fields {
name: Node::new(Identifier::new("Foo"), (7, 10)),
fields: vec![
(
Node::new(Identifier::new("a"), (13, 14)),
Node::new(Type::Integer, (16, 19))
),
(
Node::new(Identifier::new("b"), (21, 22)),
Node::new(Type::Float, (24, 29))
)
]
},
(0, 31)
)
]))
);
}
#[test]
fn tuple_struct_instantiation() {
let source = "Foo(1, 2.0)";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::call(
Expression::identifier(Identifier::new("Foo"), (0, 3)),
vec![
Expression::literal(1, (4, 5)),
Expression::literal(2.0, (7, 10))
],
(0, 11)
))
]))
);
}
#[test]
fn tuple_struct_definition() {
let source = "struct Foo(int, float);";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::StructDefinition(Node::new(
StructDefinition::Tuple {
name: Node::new(Identifier::new("Foo"), (7, 10)),
items: vec![
Node::new(Type::Integer, (11, 14)),
Node::new(Type::Float, (16, 21)),
],
},
(0, 23)
))
]))
);
}
#[test]
fn unit_struct() {
let source = "struct Foo;";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::StructDefinition(Node::new(
StructDefinition::Unit {
name: Node::new(Identifier::new("Foo"), (7, 10)),
},
(0, 11)
))
]))
);
}
#[test]
fn list_index_nested() {
let source = "[1, [2], 3][1][0]";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::list_index(
Expression::list_index(
Expression::list(
[
Expression::literal(1, (1, 2)),
Expression::list([Expression::literal(2, (5, 6))], (4, 7)),
Expression::literal(3, (9, 10)),
],
(0, 11)
),
Expression::literal(1, (12, 13)),
(0, 14)
),
Expression::literal(0, (15, 16)),
(0, 17)
),)
]))
);
}
#[test]
fn range() {
let source = "0..42";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::exclusive_range(
Expression::literal(0, (0, 1)),
Expression::literal(42, (3, 5)),
(0, 5)
))
]))
);
}
#[test]
fn negate_variable() {
let source = "a = 1; -a";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::ExpressionNullified(Node::new(
Expression::operator(
OperatorExpression::Assignment {
assignee: Expression::identifier(Identifier::new("a"), (0, 1)),
value: Expression::literal(1, (4, 5)),
},
(0, 5)
),
(0, 6)
)),
Statement::Expression(Expression::operator(
OperatorExpression::Negation(Expression::identifier(
Identifier::new("a"),
(8, 9)
)),
(7, 9)
))
]))
);
}
#[test]
fn negate_expression() {
let source = "-(1 + 1)";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::operator(
OperatorExpression::Negation(Expression::grouped(
Expression::operator(
OperatorExpression::Math {
left: Expression::literal(1, (2, 3)),
operator: Node::new(MathOperator::Add, (4, 5)),
right: Expression::literal(1, (6, 7)),
},
(2, 7)
),
(1, 8)
)),
(0, 8)
))
]))
);
}
#[test]
fn not_expression() {
let source = "!(1 > 42)";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::operator(
OperatorExpression::Not(Expression::grouped(
Expression::operator(
OperatorExpression::Comparison {
left: Expression::literal(1, (2, 3)),
operator: Node::new(ComparisonOperator::GreaterThan, (4, 5)),
right: Expression::literal(42, (6, 8)),
},
(2, 8)
),
(1, 9)
)),
(0, 9)
))
]))
);
}
#[test]
fn not_variable() {
let source = "a = false; !a";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::ExpressionNullified(Node::new(
Expression::operator(
OperatorExpression::Assignment {
assignee: Expression::identifier(Identifier::new("a"), (0, 1)),
value: Expression::literal(false, (4, 9)),
},
(0, 9)
),
(0, 10)
)),
Statement::Expression(Expression::operator(
OperatorExpression::Not(Expression::identifier(Identifier::new("a"), (12, 13))),
(11, 13)
)),
]))
);
}
#[test]
fn r#if() {
let source = "if x { y }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::r#if(
IfExpression::If {
condition: Expression::identifier(Identifier::new("x"), (3, 4)),
if_block: Node::new(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::identifier(
Identifier::new("y"),
(7, 8)
))
])),
(5, 10)
)
},
(0, 10)
))
]))
);
}
#[test]
fn if_else() {
let source = "if x { y } else { z }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::r#if(
IfExpression::IfElse {
condition: Expression::identifier(Identifier::new("x"), (3, 4)),
if_block: Node::new(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::identifier(
Identifier::new("y"),
(7, 8)
))
])),
(5, 10)
),
r#else: ElseExpression::Block(Node::new(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::identifier(
Identifier::new("z"),
(18, 19)
))
])),
(16, 21)
))
},
(0, 21)
))
]))
);
}
#[test]
fn if_else_if_else() {
let source = "if x { y } else if z { a } else { b }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::r#if(
IfExpression::IfElse {
condition: Expression::identifier(Identifier::new("x"), (3, 4)),
if_block: Node::new(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::identifier(
Identifier::new("y"),
(7, 8)
))
])),
(5, 10)
),
r#else: ElseExpression::If(Node::new(
Box::new(IfExpression::IfElse {
condition: Expression::identifier(Identifier::new("z"), (19, 20)),
if_block: Node::new(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::identifier(
Identifier::new("a"),
(23, 24)
))
])),
(21, 26)
),
r#else: ElseExpression::Block(Node::new(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::identifier(
Identifier::new("b"),
(34, 35)
))
])),
(32, 37)
)),
}),
(16, 37)
)),
},
(0, 37)
))
]))
)
}
#[test]
fn while_loop() {
let source = "while x < 10 { x += 1 }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::while_loop(
Expression::operator(
OperatorExpression::Comparison {
left: Expression::identifier(Identifier::new("x"), (6, 7)),
operator: Node::new(ComparisonOperator::LessThan, (8, 9)),
right: Expression::literal(10, (10, 12)),
},
(6, 12)
),
Node::new(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::operator(
OperatorExpression::CompoundAssignment {
assignee: Expression::identifier(
Identifier::new("x"),
(15, 16)
),
operator: Node::new(MathOperator::Add, (17, 19)),
modifier: Expression::literal(1, (20, 21)),
},
(15, 21)
))
])),
(13, 23)
),
(0, 23)
))
]))
)
}
#[test]
fn add_assign() {
let source = "a += 1";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::operator(
OperatorExpression::CompoundAssignment {
assignee: Expression::identifier(Identifier::new("a"), (0, 1)),
operator: Node::new(MathOperator::Add, (2, 4)),
modifier: Expression::literal(1, (5, 6)),
},
(0, 6)
))
]))
)
}
#[test]
fn or() {
let source = "true || false";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::operator(
OperatorExpression::Logic {
left: Expression::literal(true, (0, 4)),
operator: Node::new(LogicOperator::Or, (5, 7)),
right: Expression::literal(false, (8, 13)),
},
(0, 13)
))
]))
)
}
#[test]
fn block_with_one_statement() {
let source = "{ 40 + 2 }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::block(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::operator(
OperatorExpression::Math {
left: Expression::literal(40, (2, 4)),
operator: Node::new(MathOperator::Add, (5, 6)),
right: Expression::literal(2, (7, 8)),
},
(2, 8)
))
])),
(0, 10)
))
]))
)
}
#[test]
fn block_with_assignment() {
let source = "{ foo = 42; bar = 42; baz = \"42\" }";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::block(
BlockExpression::Sync(AbstractSyntaxTree::with_statements([
Statement::ExpressionNullified(Node::new(
Expression::assignment(
Expression::identifier("foo", (2, 5)),
Expression::literal(42, (8, 10)),
(2, 10)
),
(2, 11)
)),
Statement::ExpressionNullified(Node::new(
Expression::assignment(
Expression::identifier("bar", (12, 15)),
Expression::literal(42, (18, 20)),
(12, 20)
),
(12, 21)
)),
Statement::Expression(Expression::assignment(
Expression::identifier("baz", (22, 25)),
Expression::literal("42", (28, 32)),
(22, 32)
))
])),
(0, 34)
))
]))
)
}
#[test]
fn equal() {
let source = "42 == 42";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::comparison(
Expression::literal(42, (0, 2)),
Node::new(ComparisonOperator::Equal, (3, 5)),
Expression::literal(42, (6, 8)),
(0, 8)
))
]))
);
}
#[test]
fn less_than() {
let source = "1 < 2";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::comparison(
Expression::literal(1, (0, 1)),
Node::new(ComparisonOperator::LessThan, (2, 3)),
Expression::literal(2, (4, 5)),
(0, 5)
))
]))
);
}
#[test]
fn less_than_or_equal() {
let source = "1 <= 2";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::comparison(
Expression::literal(1, (0, 1)),
Node::new(ComparisonOperator::LessThanOrEqual, (2, 4)),
Expression::literal(2, (5, 6)),
(0, 6)
))
]))
);
}
#[test]
fn greater_than_or_equal() {
let source = "1 >= 2";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::comparison(
Expression::literal(1, (0, 1)),
Node::new(ComparisonOperator::GreaterThanOrEqual, (2, 4)),
Expression::literal(2, (5, 6)),
(0, 6)
))
]))
);
}
#[test]
fn greater_than() {
let source = "1 > 2";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::comparison(
Expression::literal(1, (0, 1)),
Node::new(ComparisonOperator::GreaterThan, (2, 3)),
Expression::literal(2, (4, 5)),
(0, 5)
))
]))
);
}
#[test]
fn subtract_negative_integers() {
let source = "-1 - -2";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::math(
Expression::literal(-1, (0, 2)),
MathOperator::subtract((3, 4)),
Expression::literal(-2, (5, 7)),
(0, 7)
))
]))
);
}
#[test]
fn modulo() {
let source = "42 % 2";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::math(
Expression::literal(42, (0, 2)),
MathOperator::modulo((3, 4)),
Expression::literal(2, (5, 6)),
(0, 6)
))
]))
);
}
#[test]
fn divide() {
let source = "42 / 2";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::math(
Expression::literal(42, (0, 2)),
MathOperator::divide((3, 4)),
Expression::literal(2, (5, 6)),
(0, 6)
))
]))
);
}
#[test]
fn string_concatenation() {
let source = "\"Hello, \" + \"World!\"";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::math(
Expression::literal("Hello, ", (0, 9)),
MathOperator::add((10, 11)),
Expression::literal("World!", (12, 20)),
(0, 20)
))
]))
);
}
#[test]
fn string() {
let source = "\"Hello, World!\"";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::literal("Hello, World!", (0, 15)))
]))
);
}
#[test]
fn boolean() {
let source = "true";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::literal(true, (0, 4)))
]))
);
}
#[test]
fn list_index() {
let source = "[1, 2, 3][0]";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::list_index(
Expression::list(
[
Expression::literal(1, (1, 2)),
Expression::literal(2, (4, 5)),
Expression::literal(3, (7, 8)),
],
(0, 9)
),
Expression::literal(0, (10, 11)),
(0, 12)
))
]))
);
}
#[test]
fn property_access() {
let source = "a.b";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::field_access(
Expression::identifier(Identifier::new("a"), (0, 1)),
Node::new(Identifier::new("b"), (2, 3)),
(0, 3)
))
]))
);
}
#[test]
fn complex_list() {
let source = "[1, 1 + 1, 2 + (4 * 10)]";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::list(
[
Expression::literal(1, (1, 2)),
Expression::math(
Expression::literal(1, (4, 5)),
MathOperator::add((6, 7)),
Expression::literal(1, (8, 9)),
(4, 9)
),
Expression::math(
Expression::literal(2, (11, 12)),
Node::new(MathOperator::Add, (13, 14)),
Expression::grouped(
Expression::math(
Expression::literal(4, (16, 17)),
MathOperator::multiply((18, 19)),
Expression::literal(10, (20, 22)),
(16, 22)
),
(15, 23)
),
(11, 23)
),
],
(0, 24)
))
]))
);
}
#[test]
fn list() {
let source = "[1, 2]";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::list(
[
Expression::literal(1, (1, 2)),
Expression::literal(2, (4, 5))
],
(0, 6)
))
]))
);
}
#[test]
fn empty_list() {
let source = "[]";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::list(vec![], (0, 2)))
]))
);
}
#[test]
fn float() {
let source = "42.0";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::literal(42.0, (0, 4)))
]))
);
}
#[test]
fn add() {
let source = "1 + 2";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::math(
Expression::literal(1, (0, 1)),
MathOperator::add((2, 3)),
Expression::literal(2, (4, 5)),
(0, 5)
))
]))
);
}
#[test]
fn multiply() {
let source = "1 * 2";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::math(
Expression::literal(1, (0, 1)),
MathOperator::multiply((2, 3)),
Expression::literal(2, (4, 5)),
(0, 5)
),)
]))
);
}
#[test]
fn add_and_multiply() {
let source = "1 + 2 * 3";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::math(
Expression::literal(1, (0, 1)),
MathOperator::add((2, 3)),
Expression::math(
Expression::literal(2, (4, 5)),
MathOperator::multiply((6, 7)),
Expression::literal(3, (8, 9)),
(4, 9)
),
(0, 9)
)),
]))
);
}
#[test]
fn assignment() {
let source = "a = 1 + 2 * 3";
assert_eq!(
parse(source),
Ok(AbstractSyntaxTree::with_statements([
Statement::Expression(Expression::assignment(
Expression::identifier("a", (0, 1)),
Expression::math(
Expression::literal(1, (4, 5)),
MathOperator::add((6, 7)),
Expression::math(
Expression::literal(2, (8, 9)),
MathOperator::multiply((10, 11)),
Expression::literal(3, (12, 13)),
(8, 13)
),
(4, 13)
),
(0, 13)
))
]))
);
}
}