beenull/ladybird
1
0
Fork 0
mirror of https://github.com/LadybirdBrowser/ladybird.git synced 2024-11-25 17:10:23 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 7

LibJS: Fix broken parsing of !o.a

Browse source 
Unary expressions parsing now respects precedence and associativity of
operators. This patch also makes `typeof` left-associative which was
an oversight.

Thanks to Conrad for helping me work this out. :^)
This commit is contained in:
Andreas Kling 2020-03-28 11:48:52 +01:00
parent f1a074a262
commit 14de45296e
Notes: sideshowbarker 2024-07-19 08:05:55 +09:00 
Author: https://github.com/awesomekling
Commit: https://github.com/SerenityOS/serenity/commit/14de45296eb
2 changed files with 26 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

13
Libraries/LibJS/Parser.cpp
View file

@ -150,6 +150,7 @@ Associativity Parser::operator_associativity(TokenType type) const
case TokenType::ExclamationMarkEquals:
case TokenType::EqualsEqualsEquals:
case TokenType::ExclamationMarkEqualsEquals:
case TokenType::Typeof:
case TokenType::Ampersand:
case TokenType::Caret:
case TokenType::Pipe:
@ -256,22 +257,24 @@ NonnullRefPtr<Expression> Parser::parse_primary_expression()
NonnullRefPtr<Expression> Parser::parse_unary_prefixed_expression()
{
auto precedence = operator_precedence(m_current_token.type());
auto associativity = operator_associativity(m_current_token.type());
switch (m_current_token.type()) {
case TokenType::PlusPlus:
consume();
return create_ast_node<UpdateExpression>(UpdateOp::Increment, parse_primary_expression(), true);
return create_ast_node<UpdateExpression>(UpdateOp::Increment, parse_expression(precedence, associativity), true);
case TokenType::MinusMinus:
consume();
return create_ast_node<UpdateExpression>(UpdateOp::Decrement, parse_primary_expression(), true);
return create_ast_node<UpdateExpression>(UpdateOp::Decrement, parse_expression(precedence, associativity), true);
case TokenType::ExclamationMark:
consume();
return create_ast_node<UnaryExpression>(UnaryOp::Not, parse_primary_expression());
return create_ast_node<UnaryExpression>(UnaryOp::Not, parse_expression(precedence, associativity));
case TokenType::Tilde:
consume();
return create_ast_node<UnaryExpression>(UnaryOp::BitwiseNot, parse_primary_expression());
return create_ast_node<UnaryExpression>(UnaryOp::BitwiseNot, parse_expression(precedence, associativity));
case TokenType::Typeof:
consume();
return create_ast_node<UnaryExpression>(UnaryOp::Typeof, parse_primary_expression());
return create_ast_node<UnaryExpression>(UnaryOp::Typeof, parse_expression(precedence, associativity));
default:
m_has_errors = true;
expected("primary expression (missing switch case)");

18
Libraries/LibJS/Tests/parser-unary-associativity.js Normal file
View file

@ -0,0 +1,18 @@
function assert(x) { if (!x) throw 1; }
try {
var o = {};
o.a = 1;
assert(o.a === 1);
assert(!o.a === false);
assert(!o.a === !(o.a));
assert(~o.a === ~(o.a));
assert((typeof "x" === "string") === true);
assert(!(typeof "x" === "string") === false);
console.log("PASS");
} catch (e) {
console.log("FAIL: " + e);
}