2026-03-24 13:40:28 +00:00

1339 lines
47 KiB
Rust

use crate::common::diagnostics::{Diagnostic, DiagnosticBundle, Severity};
use crate::common::spans::{FileId, Span};
use crate::frontends::pbs::ast::*;
use crate::frontends::pbs::lexer::Lexer;
use crate::frontends::pbs::token::{Token, TokenKind};
use prometeu_analysis::{NameId, NameInterner, NodeId};
pub struct Parser<'a> {
tokens: Vec<Token>,
pos: usize,
file_id: FileId,
errors: Vec<Diagnostic>,
interner: &'a mut NameInterner,
arena: AstArena,
builtin_none: NameId,
builtin_some: NameId,
builtin_ok: NameId,
builtin_err: NameId,
builtin_true: NameId,
builtin_false: NameId,
builtin_void: NameId,
builtin_array: NameId,
builtin_optional: NameId,
builtin_result: NameId,
builtin_bounded: NameId,
}
impl<'a> Parser<'a> {
pub fn new(source: &str, file_id: FileId, interner: &'a mut NameInterner) -> Self {
let mut lexer = Lexer::new(source, file_id);
let mut tokens = Vec::new();
loop {
let token = lexer.next_token();
let is_eof = token.kind == TokenKind::Eof;
tokens.push(token);
if is_eof {
break;
}
}
let builtin_none = interner.intern("none");
let builtin_some = interner.intern("some");
let builtin_ok = interner.intern("ok");
let builtin_err = interner.intern("err");
let builtin_true = interner.intern("true");
let builtin_false = interner.intern("false");
let builtin_void = interner.intern("void");
let builtin_array = interner.intern("array");
let builtin_optional = interner.intern("optional");
let builtin_result = interner.intern("result");
let builtin_bounded = interner.intern("bounded");
Self {
tokens,
pos: 0,
file_id,
errors: Vec::new(),
interner,
arena: AstArena::default(),
builtin_none,
builtin_some,
builtin_ok,
builtin_err,
builtin_true,
builtin_false,
builtin_void,
builtin_array,
builtin_optional,
builtin_result,
builtin_bounded,
}
}
pub fn parse_file(&mut self) -> Result<ParsedAst, DiagnosticBundle> {
let start_span = self.peek().span.clone();
let mut imports = Vec::new();
let mut decls = Vec::new();
while self.peek().kind != TokenKind::Eof {
if self.peek().kind == TokenKind::Import {
match self.parse_import() {
Ok(imp) => imports.push(imp),
Err(_) => self.recover_to_top_level(),
}
} else {
match self.parse_top_level_decl() {
Ok(decl) => decls.push(decl),
Err(_) => self.recover_to_top_level(),
}
}
}
let end_span = self.peek().span.clone();
if !self.errors.is_empty() {
return Err(DiagnosticBundle {
diagnostics: self.errors.clone(),
});
}
let span = Span::new(self.file_id, start_span.start, end_span.end);
let root = self.arena.push(NodeKind::File(FileNodeArena { imports, decls }), span);
self.arena.roots.push(root);
Ok(ParsedAst {
arena: std::mem::take(&mut self.arena),
root,
})
}
fn recover_to_top_level(&mut self) {
while self.peek().kind != TokenKind::Eof {
match self.peek().kind {
TokenKind::Import
| TokenKind::Fn
| TokenKind::Pub
| TokenKind::Mod
| TokenKind::Declare
| TokenKind::Service => break,
_ => self.advance(),
};
}
}
fn parse_import(&mut self) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::Import)?.span;
let spec = self.parse_import_spec()?;
self.consume(TokenKind::Identifier("from".to_string()))?;
let path_tok = match self.peek().kind {
TokenKind::StringLit(ref s) => {
let s = s.clone();
let span = self.advance().span;
(s, span)
}
_ => return Err(self.error_with_code("Expected string literal after 'from'", Some("E_PARSE_EXPECTED_TOKEN"))),
};
if self.peek().kind == TokenKind::Semicolon {
self.advance();
}
let span = Span::new(self.file_id, start_span.start, path_tok.1.end);
Ok(self.arena.push(
NodeKind::Import(ImportNodeArena {
spec,
from: path_tok.0,
}),
span,
))
}
fn parse_import_spec(&mut self) -> Result<NodeId, DiagnosticBundle> {
let mut path = Vec::new();
let start_span = self.peek().span.clone();
if self.peek().kind == TokenKind::OpenBrace {
self.advance(); // {
loop {
let name = match self.peek().kind.clone() {
TokenKind::Identifier(name) => name,
_ => return Err(self.error("Expected identifier in import spec")),
};
self.advance();
path.push(self.interner.intern(&name));
if self.peek().kind == TokenKind::Comma {
self.advance();
} else if self.peek().kind == TokenKind::CloseBrace {
break;
} else {
return Err(self.error("Expected ',' or '}' in import spec"));
}
}
self.consume(TokenKind::CloseBrace)?;
} else {
loop {
let name = match self.peek().kind.clone() {
TokenKind::Identifier(name) => name,
_ => return Err(self.error("Expected identifier in import spec")),
};
self.advance();
path.push(self.interner.intern(&name));
if self.peek().kind == TokenKind::Dot {
self.advance();
} else {
break;
}
}
}
let end_span = self.tokens[self.pos - 1].span.clone();
let span = Span::new(self.file_id, start_span.start, end_span.end);
Ok(self.arena.push(NodeKind::ImportSpec(ImportSpecNodeArena { path }), span))
}
fn parse_top_level_decl(&mut self) -> Result<NodeId, DiagnosticBundle> {
match self.peek().kind {
TokenKind::Fn => self.parse_fn_decl(None),
TokenKind::Pub | TokenKind::Mod | TokenKind::Declare | TokenKind::Service => self.parse_decl(),
TokenKind::Invalid(ref msg) => {
let code = if msg.contains("Unterminated string") {
"E_LEX_UNTERMINATED_STRING"
} else {
"E_LEX_INVALID_CHAR"
};
let msg = msg.clone();
Err(self.error_with_code(&msg, Some(code)))
}
_ => Err(self.error_with_code("Expected top-level declaration", Some("E_PARSE_UNEXPECTED_TOKEN"))),
}
}
fn parse_decl(&mut self) -> Result<NodeId, DiagnosticBundle> {
let vis = if self.peek().kind == TokenKind::Pub {
self.advance();
Some("pub".to_string())
} else if self.peek().kind == TokenKind::Mod {
self.advance();
Some("mod".to_string())
} else {
None
};
match self.peek().kind {
TokenKind::Service => self.parse_service_decl(vis),
TokenKind::Declare => self.parse_type_decl(vis),
TokenKind::Fn => self.parse_fn_decl(vis),
_ => Err(self.error("Expected 'service', 'declare', or 'fn'")),
}
}
fn parse_service_decl(&mut self, vis: Option<String>) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::Service)?.span;
let name = self.expect_identifier()?;
let mut extends = None;
if self.peek().kind == TokenKind::Colon {
self.advance();
extends = Some(self.expect_identifier()?);
}
self.consume(TokenKind::OpenBrace)?;
let mut members = Vec::new();
while self.peek().kind != TokenKind::CloseBrace && self.peek().kind != TokenKind::Eof {
members.push(self.parse_service_member()?);
// Optional semicolon after signature
if self.peek().kind == TokenKind::Semicolon {
self.advance();
}
}
let end_span = self.consume(TokenKind::CloseBrace)?.span;
let span = Span::new(self.file_id, start_span.start, end_span.end);
Ok(self.arena.push(
NodeKind::ServiceDecl(ServiceDeclNodeArena {
vis,
name,
extends,
members,
}),
span,
))
}
fn parse_service_member(&mut self) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::Fn)?.span;
let name = self.expect_identifier()?;
let params = self.parse_param_list()?;
let ret = if self.peek().kind == TokenKind::Colon {
self.advance();
self.parse_type_ref()?
} else {
self.arena.push(
NodeKind::TypeName(TypeNameNodeArena {
name: self.builtin_void,
}),
Span::new(self.file_id, 0, 0),
)
};
let span = Span::new(self.file_id, start_span.start, self.arena.span(ret).end);
Ok(self.arena.push(
NodeKind::ServiceFnSig(ServiceFnSigNodeArena { name, params, ret }),
span,
))
}
fn parse_type_decl(&mut self, vis: Option<String>) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::Declare)?.span;
let type_kind = match self.peek().kind {
TokenKind::Struct => { self.advance(); "struct".to_string() }
TokenKind::Contract => { self.advance(); "contract".to_string() }
TokenKind::Error => { self.advance(); "error".to_string() }
_ => return Err(self.error_with_code("Expected 'struct', 'contract', or 'error'", Some("E_PARSE_EXPECTED_TOKEN"))),
};
let name = self.expect_identifier()?;
let mut params = Vec::new();
if self.peek().kind == TokenKind::OpenParen {
params = self.parse_param_list()?;
}
let mut constructors = Vec::new();
if self.peek().kind == TokenKind::OpenBracket {
constructors = self.parse_constructor_list()?;
}
let mut is_host = false;
if self.peek().kind == TokenKind::Host {
self.advance();
is_host = true;
}
let mut constants = Vec::new();
if self.peek().kind == TokenKind::OpenDoubleBracket {
self.advance();
while self.peek().kind != TokenKind::CloseDoubleBracket && self.peek().kind != TokenKind::Eof {
let c_start = self.peek().span.start;
let c_name = self.expect_identifier()?;
self.consume(TokenKind::Colon)?;
let c_value = self.parse_expr(0)?;
let c_span = Span::new(self.file_id, c_start, self.arena.span(c_value).end);
constants.push(self.arena.push(
NodeKind::ConstantDecl(ConstantDeclNodeArena {
name: c_name,
value: c_value,
}),
c_span,
));
if self.peek().kind == TokenKind::Comma {
self.advance();
}
}
self.consume(TokenKind::CloseDoubleBracket)?;
}
let mut body = None;
if self.peek().kind == TokenKind::OpenBrace {
body = Some(self.parse_type_body()?);
}
let mut end_pos = start_span.end;
if let Some(b) = body {
end_pos = self.arena.span(b).end;
body = Some(b);
} else if !constants.is_empty() {
// We should use the CloseDoubleBracket span here, but I don't have it easily
// Let's just use the last constant's end
end_pos = self.arena.span(*constants.last().unwrap()).end;
} else if !params.is_empty() {
end_pos = params.last().unwrap().span.end;
}
let span = Span::new(self.file_id, start_span.start, end_pos);
Ok(self.arena.push(
NodeKind::TypeDecl(TypeDeclNodeArena {
vis,
type_kind,
name,
is_host,
params,
constructors,
constants,
body,
}),
span,
))
}
fn parse_type_body(&mut self) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::OpenBrace)?.span;
let mut members = Vec::new();
let mut methods = Vec::new();
while self.peek().kind != TokenKind::CloseBrace && self.peek().kind != TokenKind::Eof {
if self.peek().kind == TokenKind::Fn {
let sig_node = self.parse_service_member()?;
methods.push(sig_node);
if self.peek().kind == TokenKind::Semicolon {
self.advance();
}
} else {
let m_start = self.peek().span.start;
let name = self.expect_identifier()?;
self.consume(TokenKind::Colon)?;
let ty = self.parse_type_ref()?;
let m_end = self.arena.span(ty).end;
members.push(TypeMemberNodeArena {
span: Span::new(self.file_id, m_start, m_end),
name,
ty,
});
if self.peek().kind == TokenKind::Comma {
self.advance();
} else if self.peek().kind == TokenKind::Semicolon {
self.advance();
}
}
}
let end_span = self.consume(TokenKind::CloseBrace)?.span;
let span = Span::new(self.file_id, start_span.start, end_span.end);
Ok(self.arena.push(
NodeKind::TypeBody(TypeBodyNodeArena { members, methods }),
span,
))
}
fn parse_fn_decl(&mut self, vis: Option<String>) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::Fn)?.span;
let name = self.expect_identifier()?;
let params = self.parse_param_list()?;
let _ret = if self.peek().kind == TokenKind::Colon {
self.advance();
Some(self.parse_type_ref()?)
} else {
None
};
let mut else_fallback = None;
if self.peek().kind == TokenKind::Else {
self.advance();
else_fallback = Some(self.parse_block()?);
}
let body = self.parse_block()?;
let body_span = self.arena.span(body);
let span = Span::new(self.file_id, start_span.start, body_span.end);
Ok(self.arena.push(
NodeKind::FnDecl(FnDeclNodeArena {
vis,
name,
params,
ret: _ret,
else_fallback,
body,
}),
span,
))
}
fn parse_param_list(&mut self) -> Result<Vec<ParamNodeArena>, DiagnosticBundle> {
self.consume(TokenKind::OpenParen)?;
let mut params = Vec::new();
while self.peek().kind != TokenKind::CloseParen && self.peek().kind != TokenKind::Eof {
let p_start = self.peek().span.start;
let name = self.expect_identifier()?;
self.consume(TokenKind::Colon)?;
let ty = self.parse_type_ref()?;
let p_end = self.arena.span(ty).end;
params.push(ParamNodeArena {
span: Span::new(self.file_id, p_start, p_end),
name,
ty,
});
if self.peek().kind == TokenKind::Comma {
self.advance();
} else {
break;
}
}
self.consume(TokenKind::CloseParen)?;
Ok(params)
}
fn parse_type_ref(&mut self) -> Result<NodeId, DiagnosticBundle> {
let id_tok = self.peek().clone();
let name = match id_tok.kind {
TokenKind::Identifier(ref s) => {
self.advance();
self.interner.intern(s)
}
TokenKind::Optional => {
self.advance();
self.builtin_optional
}
TokenKind::Result => {
self.advance();
self.builtin_result
}
TokenKind::Bounded => {
self.advance();
self.builtin_bounded
}
TokenKind::None => {
self.advance();
self.builtin_none
}
TokenKind::Some => {
self.advance();
self.builtin_some
}
TokenKind::Ok => {
self.advance();
self.builtin_ok
}
TokenKind::Err => {
self.advance();
self.builtin_err
}
_ => return Err(self.error_with_code("Expected type name", Some("E_PARSE_EXPECTED_TOKEN"))),
};
let mut node = if self.peek().kind == TokenKind::Lt {
self.advance(); // <
let mut args = Vec::new();
loop {
args.push(self.parse_type_ref()?);
if self.peek().kind == TokenKind::Comma {
self.advance();
} else {
break;
}
}
let end_tok = self.consume(TokenKind::Gt)?;
self.arena.push(
NodeKind::TypeApp(TypeAppNodeArena { base: name, args }),
Span::new(self.file_id, id_tok.span.start, end_tok.span.end),
)
} else {
self.arena.push(
NodeKind::TypeName(TypeNameNodeArena { name }),
id_tok.span,
)
};
if self.peek().kind == TokenKind::OpenBracket {
self.advance();
let size_tok = self.peek().clone();
let size = match size_tok.kind {
TokenKind::IntLit(v) => {
self.advance();
v as u32
}
TokenKind::BoundedLit(v) => {
self.advance();
v
}
_ => {
return Err(self.error_with_code(
"integer or bounded literal for array size",
Some("E_PARSE_EXPECTED_TOKEN"),
))
}
};
let end_tok = self.consume(TokenKind::CloseBracket)?;
let size_node = self.arena.push(
NodeKind::IntLit(IntLitNodeArena { value: size as i64 }),
size_tok.span,
);
let span = Span::new(self.file_id, self.arena.span(node).start, end_tok.span.end);
let mut wrapped = true;
let index = node.0 as usize;
if let NodeKind::TypeApp(ta) = &mut self.arena.nodes[index] {
if ta.base == self.builtin_array {
ta.args.push(size_node);
self.arena.spans[index] = span.clone();
wrapped = false;
}
}
if wrapped {
node = self.arena.push(
NodeKind::TypeApp(TypeAppNodeArena {
base: self.builtin_array,
args: vec![node, size_node],
}),
span,
);
}
}
Ok(node)
}
fn parse_block(&mut self) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::OpenBrace)?.span;
let mut stmts = Vec::new();
let mut tail = None;
while self.peek().kind != TokenKind::CloseBrace && self.peek().kind != TokenKind::Eof {
if self.peek().kind == TokenKind::Let {
stmts.push(self.parse_let_stmt()?);
} else if self.peek().kind == TokenKind::Return {
stmts.push(self.parse_return_stmt()?);
} else {
let expr = self.parse_expr(0)?;
if self.peek().kind == TokenKind::Semicolon {
let semi_span = self.advance().span;
let expr_start = self.arena.span(expr).start;
let span = Span::new(self.file_id, expr_start, semi_span.end);
stmts.push(self.arena.push(
NodeKind::ExprStmt(ExprStmtNodeArena { expr }),
span,
));
} else if self.peek().kind == TokenKind::CloseBrace {
tail = Some(expr);
} else {
// Treat as ExprStmt even without semicolon (e.g. for if/when used as statement)
let expr_span = self.arena.span(expr);
stmts.push(self.arena.push(
NodeKind::ExprStmt(ExprStmtNodeArena { expr }),
expr_span,
));
}
}
}
let end_span = self.consume(TokenKind::CloseBrace)?.span;
let span = Span::new(self.file_id, start_span.start, end_span.end);
Ok(self.arena.push(NodeKind::Block(BlockNodeArena { stmts, tail }), span))
}
fn parse_let_stmt(&mut self) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::Let)?.span;
let is_mut = if self.peek().kind == TokenKind::Mut {
self.advance();
true
} else {
false
};
let name = self.expect_identifier()?;
let ty = if self.peek().kind == TokenKind::Colon {
self.advance();
Some(self.parse_type_ref()?)
} else {
None
};
self.consume(TokenKind::Assign)?;
let init = self.parse_expr(0)?;
let end_span = self.consume(TokenKind::Semicolon)?.span;
let span = Span::new(self.file_id, start_span.start, end_span.end);
Ok(self.arena.push(
NodeKind::LetStmt(LetStmtNodeArena {
name,
is_mut,
ty,
init,
}),
span,
))
}
fn parse_return_stmt(&mut self) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::Return)?.span;
let mut expr = None;
if self.peek().kind != TokenKind::Semicolon {
expr = Some(self.parse_expr(0)?);
}
let end_span = self.consume(TokenKind::Semicolon)?.span;
let span = Span::new(self.file_id, start_span.start, end_span.end);
Ok(self.arena.push(NodeKind::ReturnStmt(ReturnStmtNodeArena { expr }), span))
}
fn parse_alloc(&mut self) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::Alloc)?.span;
let ty = self.parse_type_ref()?;
let span = Span::new(self.file_id, start_span.start, self.arena.span(ty).end);
Ok(self.arena.push(NodeKind::Alloc(AllocNodeArena { ty }), span))
}
fn parse_mutate_borrow_peek(&mut self, kind: TokenKind) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(kind.clone())?.span;
let target_expr = self.parse_expr(0)?;
let (target, binding) = if let NodeKind::Cast(cast) = self.arena.kind(target_expr) {
let binding = match self.arena.kind(cast.ty) {
NodeKind::Ident(id) => Some(id.name),
NodeKind::TypeName(tn) => Some(tn.name),
_ => None,
};
if let Some(binding) = binding {
(cast.expr, binding)
} else {
return Err(self.error_with_code(
"Expected binding name after 'as'",
Some("E_PARSE_EXPECTED_TOKEN"),
));
}
} else {
self.consume(TokenKind::As)?;
let binding = self.expect_identifier()?;
(target_expr, binding)
};
let body = self.parse_block()?;
let span = Span::new(self.file_id, start_span.start, self.arena.span(body).end);
match kind {
TokenKind::Mutate => Ok(self.arena.push(
NodeKind::Mutate(MutateNodeArena { target, binding, body }),
span,
)),
TokenKind::Borrow => Ok(self.arena.push(
NodeKind::Borrow(BorrowNodeArena { target, binding, body }),
span,
)),
TokenKind::Peek => Ok(self.arena.push(
NodeKind::Peek(PeekNodeArena { target, binding, body }),
span,
)),
_ => unreachable!(),
}
}
fn parse_expr(&mut self, min_precedence: u8) -> Result<NodeId, DiagnosticBundle> {
let mut left = self.parse_primary()?;
loop {
let (op, precedence) = match self.get_binary_precedence() {
Some((op, p)) if p >= min_precedence => (op, p),
_ => break,
};
self.advance();
let right = self.parse_expr(precedence + 1)?;
let span = Span::new(
self.file_id,
self.arena.span(left).start,
self.arena.span(right).end,
);
left = self.arena.push(
NodeKind::Binary(BinaryNodeArena { op, left, right }),
span,
);
}
Ok(left)
}
fn parse_primary(&mut self) -> Result<NodeId, DiagnosticBundle> {
let tok = self.peek().clone();
match tok.kind {
TokenKind::IntLit(v) => {
self.advance();
Ok(self.arena.push(
NodeKind::IntLit(IntLitNodeArena { value: v }),
tok.span,
))
}
TokenKind::FloatLit(v) => {
self.advance();
Ok(self.arena.push(
NodeKind::FloatLit(FloatLitNodeArena { value: v }),
tok.span,
))
}
TokenKind::BoundedLit(v) => {
self.advance();
Ok(self.arena.push(
NodeKind::BoundedLit(BoundedLitNodeArena { value: v }),
tok.span,
))
}
TokenKind::StringLit(s) => {
self.advance();
Ok(self.arena.push(
NodeKind::StringLit(StringLitNodeArena { value: s }),
tok.span,
))
}
TokenKind::Identifier(name) => {
self.advance();
let name = self.interner.intern(&name);
let mut node = self.arena.push(
NodeKind::Ident(IdentNodeArena { name }),
tok.span,
);
loop {
if self.peek().kind == TokenKind::OpenParen {
node = self.parse_call(node)?;
} else if self.peek().kind == TokenKind::As {
node = self.parse_cast(node)?;
} else if self.peek().kind == TokenKind::Dot {
node = self.parse_member_access(node)?;
} else {
break;
}
}
Ok(node)
}
TokenKind::None | TokenKind::Some | TokenKind::Ok | TokenKind::Err => {
let name = match tok.kind {
TokenKind::None => self.builtin_none,
TokenKind::Some => self.builtin_some,
TokenKind::Ok => self.builtin_ok,
TokenKind::Err => self.builtin_err,
_ => unreachable!(),
};
self.advance();
let mut node = self.arena.push(
NodeKind::Ident(IdentNodeArena { name }),
tok.span,
);
loop {
if self.peek().kind == TokenKind::OpenParen {
node = self.parse_call(node)?;
} else if self.peek().kind == TokenKind::As {
node = self.parse_cast(node)?;
} else if self.peek().kind == TokenKind::Dot {
node = self.parse_member_access(node)?;
} else {
break;
}
}
Ok(node)
}
TokenKind::OpenParen => {
self.advance();
let expr = self.parse_expr(0)?;
self.consume(TokenKind::CloseParen)?;
Ok(expr)
}
TokenKind::OpenBrace => self.parse_block(),
TokenKind::If => self.parse_if_expr(),
TokenKind::When => self.parse_when_expr(),
TokenKind::Alloc => self.parse_alloc(),
TokenKind::Mutate => self.parse_mutate_borrow_peek(TokenKind::Mutate),
TokenKind::Borrow => self.parse_mutate_borrow_peek(TokenKind::Borrow),
TokenKind::Peek => self.parse_mutate_borrow_peek(TokenKind::Peek),
TokenKind::Minus | TokenKind::Not => {
self.advance();
let op = match tok.kind {
TokenKind::Minus => "-".to_string(),
TokenKind::Not => "!".to_string(),
_ => unreachable!(),
};
let expr = self.parse_expr(11)?;
let span = Span::new(self.file_id, tok.span.start, self.arena.span(expr).end);
Ok(self.arena.push(
NodeKind::Unary(UnaryNodeArena { op, expr }),
span,
))
}
TokenKind::Invalid(msg) => {
let code = if msg.contains("Unterminated string") {
"E_LEX_UNTERMINATED_STRING"
} else {
"E_LEX_INVALID_CHAR"
};
Err(self.error_with_code(&msg, Some(code)))
}
_ => Err(self.error_with_code("Expected expression", Some("E_PARSE_UNEXPECTED_TOKEN"))),
}
}
fn parse_member_access(&mut self, object: NodeId) -> Result<NodeId, DiagnosticBundle> {
self.consume(TokenKind::Dot)?;
let member = self.expect_identifier()?;
let span = Span::new(
self.file_id,
self.arena.span(object).start,
self.tokens[self.pos - 1].span.end,
);
Ok(self.arena.push(
NodeKind::MemberAccess(MemberAccessNodeArena { object, member }),
span,
))
}
fn parse_call(&mut self, callee: NodeId) -> Result<NodeId, DiagnosticBundle> {
self.consume(TokenKind::OpenParen)?;
let mut args = Vec::new();
while self.peek().kind != TokenKind::CloseParen && self.peek().kind != TokenKind::Eof {
args.push(self.parse_expr(0)?);
if self.peek().kind == TokenKind::Comma {
self.advance();
} else {
break;
}
}
let end_span = self.consume(TokenKind::CloseParen)?.span;
let span = Span::new(self.file_id, self.arena.span(callee).start, end_span.end);
Ok(self.arena.push(
NodeKind::Call(CallNodeArena { callee, args }),
span,
))
}
fn parse_cast(&mut self, expr: NodeId) -> Result<NodeId, DiagnosticBundle> {
self.consume(TokenKind::As)?;
let ty = self.parse_type_ref()?;
let span = Span::new(self.file_id, self.arena.span(expr).start, self.arena.span(ty).end);
Ok(self.arena.push(NodeKind::Cast(CastNodeArena { expr, ty }), span))
}
fn parse_if_expr(&mut self) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::If)?.span;
let cond = self.parse_expr(0)?;
let then_block = self.parse_block()?;
let mut else_block = None;
if self.peek().kind == TokenKind::Else {
self.advance();
if self.peek().kind == TokenKind::If {
else_block = Some(self.parse_if_expr()?);
} else {
else_block = Some(self.parse_block()?);
}
}
let end_span = else_block
.map(|b| self.arena.span(b).end)
.unwrap_or(self.arena.span(then_block).end);
let span = Span::new(self.file_id, start_span.start, end_span);
Ok(self.arena.push(
NodeKind::IfExpr(IfExprNodeArena {
cond,
then_block,
else_block,
}),
span,
))
}
fn parse_when_expr(&mut self) -> Result<NodeId, DiagnosticBundle> {
let start_span = self.consume(TokenKind::When)?.span;
self.consume(TokenKind::OpenBrace)?;
let mut arms = Vec::new();
while self.peek().kind != TokenKind::CloseBrace && self.peek().kind != TokenKind::Eof {
let arm_start = self.peek().span.start;
let cond = self.parse_expr(0)?;
self.consume(TokenKind::Arrow)?;
let body = self.parse_block()?;
let arm_span = Span::new(self.file_id, arm_start, self.arena.span(body).end);
arms.push(self.arena.push(
NodeKind::WhenArm(WhenArmNodeArena { cond, body }),
arm_span,
));
if self.peek().kind == TokenKind::Comma {
self.advance();
}
}
let end_span = self.consume(TokenKind::CloseBrace)?.span;
let span = Span::new(self.file_id, start_span.start, end_span.end);
Ok(self.arena.push(NodeKind::WhenExpr(WhenExprNodeArena { arms }), span))
}
fn get_binary_precedence(&self) -> Option<(String, u8)> {
match self.peek().kind {
TokenKind::Plus => Some(("+".to_string(), 5)),
TokenKind::Minus => Some(("-".to_string(), 5)),
TokenKind::Star => Some(("*".to_string(), 4)),
TokenKind::Slash => Some(("/".to_string(), 4)),
TokenKind::Percent => Some(("%".to_string(), 4)),
TokenKind::Lt => Some(("<".to_string(), 7)),
TokenKind::Lte => Some(("<=".to_string(), 7)),
TokenKind::Gt => Some((">".to_string(), 7)),
TokenKind::Gte => Some((">=".to_string(), 7)),
TokenKind::Eq => Some(("==".to_string(), 8)),
TokenKind::Neq => Some(("!=".to_string(), 8)),
TokenKind::And => Some(("&&".to_string(), 9)),
TokenKind::Or => Some(("||".to_string(), 10)),
_ => None,
}
}
fn peek(&self) -> &Token {
&self.tokens[self.pos]
}
fn advance(&mut self) -> Token {
let tok = self.tokens[self.pos].clone();
if tok.kind != TokenKind::Eof {
self.pos += 1;
}
tok
}
fn consume(&mut self, kind: TokenKind) -> Result<Token, DiagnosticBundle> {
let peeked_kind = self.peek().kind.clone();
if peeked_kind == kind {
Ok(self.advance())
} else {
if let TokenKind::Invalid(ref msg) = peeked_kind {
let code = if msg.contains("Unterminated string") {
"E_LEX_UNTERMINATED_STRING"
} else {
"E_LEX_INVALID_CHAR"
};
let msg = msg.clone();
Err(self.error_with_code(&msg, Some(code)))
} else {
Err(self.error_with_code(&format!("Expected {:?}, found {:?}", kind, peeked_kind), Some("E_PARSE_EXPECTED_TOKEN")))
}
}
}
fn expect_identifier(&mut self) -> Result<NameId, DiagnosticBundle> {
let peeked_kind = self.peek().kind.clone();
match peeked_kind {
TokenKind::Identifier(name) => {
self.advance();
Ok(self.interner.intern(&name))
}
TokenKind::Optional => {
self.advance();
Ok(self.builtin_optional)
}
TokenKind::Result => {
self.advance();
Ok(self.builtin_result)
}
TokenKind::None => {
self.advance();
Ok(self.builtin_none)
}
TokenKind::Some => {
self.advance();
Ok(self.builtin_some)
}
TokenKind::Ok => {
self.advance();
Ok(self.builtin_ok)
}
TokenKind::Err => {
self.advance();
Ok(self.builtin_err)
}
TokenKind::Bounded => {
self.advance();
Ok(self.builtin_bounded)
}
TokenKind::Invalid(msg) => {
let code = if msg.contains("Unterminated string") {
"E_LEX_UNTERMINATED_STRING"
} else {
"E_LEX_INVALID_CHAR"
};
Err(self.error_with_code(&msg, Some(code)))
}
_ => Err(self.error_with_code(&format!("Expected identifier, found {:?}", peeked_kind), Some("E_PARSE_EXPECTED_TOKEN"))),
}
}
fn error(&mut self, message: &str) -> DiagnosticBundle {
self.error_with_code(message, None)
}
fn error_with_code(&mut self, message: &str, code: Option<&str>) -> DiagnosticBundle {
let diag = Diagnostic {
severity: Severity::Error,
code: code.unwrap_or("E_PARSE_ERROR").to_string(),
message: message.to_string(),
span: self.peek().span.clone(),
related: Vec::new(),
};
self.errors.push(diag.clone());
DiagnosticBundle::from(diag)
}
fn parse_constructor_list(&mut self) -> Result<Vec<NodeId>, DiagnosticBundle> {
self.consume(TokenKind::OpenBracket)?;
let mut constructors = Vec::new();
while self.peek().kind != TokenKind::CloseBracket && self.peek().kind != TokenKind::Eof {
let start_span = self.peek().span.clone();
let params = self.parse_param_list()?;
self.consume(TokenKind::Colon)?;
let mut initializers = Vec::new();
if self.peek().kind == TokenKind::OpenParen {
self.advance();
while self.peek().kind != TokenKind::CloseParen && self.peek().kind != TokenKind::Eof {
initializers.push(self.parse_expr(0)?);
if self.peek().kind == TokenKind::Comma {
self.advance();
}
}
self.consume(TokenKind::CloseParen)?;
} else {
initializers.push(self.parse_expr(0)?);
}
self.consume(TokenKind::As)?;
let name = self.expect_identifier()?;
let body = self.parse_block()?;
let span = Span::new(self.file_id, start_span.start, self.arena.span(body).end);
constructors.push(self.arena.push(
NodeKind::ConstructorDecl(ConstructorDeclNodeArena {
params,
initializers,
name,
body,
}),
span,
));
}
self.consume(TokenKind::CloseBracket)?;
Ok(constructors)
}
}
#[cfg(test)]
mod tests {
use super::*;
use serde_json;
use crate::common::spans::FileId;
#[test]
fn test_parse_empty_file() {
let mut interner = NameInterner::new();
let mut parser = Parser::new("", FileId(0), &mut interner);
let parsed = parser.parse_file().unwrap();
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
assert_eq!(file.imports.len(), 0);
assert_eq!(file.decls.len(), 0);
}
#[test]
fn test_parse_imports() {
let source = r#"
import std.io from "std";
import math from "./math.pbs";
"#;
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let parsed = parser.parse_file().unwrap();
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
assert_eq!(file.imports.len(), 2);
let imp = match parsed.arena.kind(file.imports[0]) {
NodeKind::Import(imp) => imp,
_ => panic!("Expected Import"),
};
assert_eq!(imp.from, "std");
let spec = match parsed.arena.kind(imp.spec) {
NodeKind::ImportSpec(spec) => spec,
_ => panic!("Expected ImportSpec"),
};
let path: Vec<&str> = spec.path.iter().map(|id| interner.resolve(*id)).collect();
assert_eq!(path, vec!["std", "io"]);
}
#[test]
fn test_parse_fn_decl() {
let source = r#"
fn add(a: int, b: int): int {
return a + b;
}
"#;
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let parsed = parser.parse_file().unwrap();
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
assert_eq!(file.decls.len(), 1);
if let NodeKind::FnDecl(f) = parsed.arena.kind(file.decls[0]) {
assert_eq!(interner.resolve(f.name), "add");
assert_eq!(f.params.len(), 2);
assert_eq!(interner.resolve(f.params[0].name), "a");
assert_eq!(interner.resolve(f.params[1].name), "b");
} else {
panic!("Expected FnDecl");
}
}
#[test]
fn test_parse_type_decl() {
let source = r#"
pub declare struct Point {
x: int,
y: int
}
"#;
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let parsed = parser.parse_file().unwrap();
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
assert_eq!(file.decls.len(), 1);
if let NodeKind::TypeDecl(t) = parsed.arena.kind(file.decls[0]) {
assert_eq!(interner.resolve(t.name), "Point");
assert_eq!(t.type_kind, "struct");
assert_eq!(t.vis, Some("pub".to_string()));
} else {
panic!("Expected TypeDecl");
}
}
#[test]
fn test_parse_service_decl() {
let source = r#"
pub service Audio {
fn play(sound: Sound);
fn stop(): bool;
}
"#;
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let parsed = parser.parse_file().unwrap();
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
assert_eq!(file.decls.len(), 1);
if let NodeKind::ServiceDecl(s) = parsed.arena.kind(file.decls[0]) {
assert_eq!(interner.resolve(s.name), "Audio");
assert_eq!(s.members.len(), 2);
} else {
panic!("Expected ServiceDecl");
}
}
#[test]
fn test_parse_expressions() {
let source = r#"
fn main() {
let x = 10 + 20 * 30;
let y = (x - 5) / 2;
foo(x, y);
}
"#;
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let parsed = parser.parse_file().unwrap();
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
assert_eq!(file.decls.len(), 1);
}
#[test]
fn test_parse_if_when() {
let source = r#"
fn main(x: int) {
if x > 0 {
print("positive");
} else {
print("non-positive");
}
let msg = when {
x == 0 -> { return "zero"; },
x == 1 -> { return "one"; }
};
}
"#;
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let parsed = parser.parse_file().unwrap();
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
assert_eq!(file.decls.len(), 1);
}
#[test]
fn test_parse_error_recovery() {
let source = r#"
fn bad() {
let x = ; // Missing init
let y = 10;
}
fn good() {}
"#;
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let result = parser.parse_file();
assert!(result.is_err());
}
#[test]
fn test_parse_mod_fn() {
let source = "mod fn test() {}";
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let parsed = parser.parse_file().expect("mod fn should be allowed");
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
if let NodeKind::FnDecl(fn_decl) = parsed.arena.kind(file.decls[0]) {
assert_eq!(fn_decl.vis, Some("mod".to_string()));
} else {
panic!("Expected FnDecl");
}
}
#[test]
fn test_parse_pub_fn() {
let source = "pub fn test() {}";
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let parsed = parser.parse_file().expect("pub fn should be allowed in parser");
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
if let NodeKind::FnDecl(fn_decl) = parsed.arena.kind(file.decls[0]) {
assert_eq!(fn_decl.vis, Some("pub".to_string()));
} else {
panic!("Expected FnDecl");
}
}
#[test]
fn test_ast_json_snapshot() {
let source = r#"
fn main() {
return 42;
}
"#;
let mut interner = NameInterner::new();
let mut parser = Parser::new(source, FileId(0), &mut interner);
let parsed = parser.parse_file().unwrap();
let file = match parsed.arena.kind(parsed.root) {
NodeKind::File(file) => file,
_ => panic!("Expected File"),
};
let json = serde_json::to_string_pretty(parsed.arena.kind(parsed.root)).unwrap();
assert!(json.contains("\"kind\": \"File\""));
if let NodeKind::FnDecl(fn_decl) = parsed.arena.kind(file.decls[0]) {
assert_eq!(interner.resolve(fn_decl.name), "main");
} else {
panic!("Expected FnDecl");
}
}
}