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use std::iter;
use crate::lexer::Lexer;
use crate::parser::Parser;
use crate::{parse_script, ParseOptions};
use ast::source_atom_set::SourceAtomSet;
use ast::source_slice_list::SourceSliceList;
use ast::{arena, source_location::SourceLocation, types::*};
use bumpalo::{self, Bump};
use generated_parser::{self, AstBuilder, ParseError, Result, TerminalId};
use std::cell::RefCell;
use std::rc::Rc;
#[cfg(all(feature = "unstable", test))]
mod benchmarks {
extern crate test;
use std::fs::File;
use std::io::Read;
use test::Bencher;
use crate::lexer::Lexer;
use crate::parse_script;
#[bench]
fn bench_parse_grammar(b: &mut Bencher) {
let mut buffer = fs::read_to_string("../vue.js").expect("reading test file");
b.iter(|| {
let lexer = Lexer::new(buffer.chars());
parse_script(lexer).unwrap();
});
}
}
trait IntoChunks<'a> {
type Chunks: Iterator<Item = &'a str>;
fn into_chunks(self) -> Self::Chunks;
}
impl<'a> IntoChunks<'a> for &'a str {
type Chunks = iter::Once<&'a str>;
fn into_chunks(self) -> Self::Chunks {
iter::once(self)
}
}
impl<'a> IntoChunks<'a> for &'a Vec<&'a str> {
type Chunks = iter::Cloned<std::slice::Iter<'a, &'a str>>;
fn into_chunks(self) -> Self::Chunks {
self.iter().cloned()
}
}
// Glue all the chunks together. XXX TODO Once the lexer supports chunks,
// we'll reimplement this to feed the code to the lexer one chunk at a time.
fn chunks_to_string<'a, T: IntoChunks<'a>>(code: T) -> String {
let mut buf = String::new();
for chunk in code.into_chunks() {
buf.push_str(chunk);
}
buf
}
fn try_parse<'alloc, 'source, Source>(
allocator: &'alloc Bump,
code: Source,
) -> Result<'alloc, arena::Box<'alloc, Script<'alloc>>>
where
Source: IntoChunks<'source>,
{
let buf = arena::alloc_str(allocator, &chunks_to_string(code));
let options = ParseOptions::new();
let atoms = Rc::new(RefCell::new(SourceAtomSet::new()));
let slices = Rc::new(RefCell::new(SourceSliceList::new()));
parse_script(allocator, &buf, &options, atoms, slices)
}
fn assert_parses<'alloc, T: IntoChunks<'alloc>>(code: T) {
let allocator = &Bump::new();
try_parse(allocator, code).unwrap();
}
fn assert_error<'alloc, T: IntoChunks<'alloc>>(code: T) {
let allocator = &Bump::new();
assert!(match try_parse(allocator, code).map_err(|e| *e) {
Err(ParseError::NotImplemented(_)) => panic!("expected error, got NotImplemented"),
Err(_) => true,
Ok(ast) => panic!("assertion failed: SUCCESS error: {:?}", ast),
});
}
fn assert_syntax_error<'alloc, T: IntoChunks<'alloc>>(code: T) {
let allocator = &Bump::new();
assert!(match try_parse(allocator, code).map_err(|e| *e) {
Err(ParseError::SyntaxError(_)) => true,
Err(other) => panic!("unexpected error: {:?}", other),
Ok(ast) => panic!("assertion failed: SUCCESS error: {:?}", ast),
});
}
fn assert_not_implemented<'alloc, T: IntoChunks<'alloc>>(code: T) {
let allocator = &Bump::new();
assert!(match try_parse(allocator, code).map_err(|e| *e) {
Err(ParseError::NotImplemented(_)) => true,
Err(other) => panic!("unexpected error: {:?}", other),
Ok(ast) => panic!("assertion failed: SUCCESS error: {:?}", ast),
});
}
fn assert_illegal_character<'alloc, T: IntoChunks<'alloc>>(code: T) {
let allocator = &Bump::new();
assert!(match try_parse(allocator, code).map_err(|e| *e) {
Err(ParseError::IllegalCharacter(_)) => true,
Err(other) => panic!("unexpected error: {:?}", other),
Ok(ast) => panic!("assertion failed: SUCCESS error: {:?}", ast),
});
}
fn assert_error_eq<'alloc, T: IntoChunks<'alloc>>(code: T, expected: ParseError) {
let allocator = &Bump::new();
let result = try_parse(allocator, code);
assert!(result.is_err());
assert_eq!(*result.unwrap_err(), expected);
}
fn assert_incomplete<'alloc, T: IntoChunks<'alloc>>(code: T) {
let allocator = &Bump::new();
let result = try_parse(allocator, code);
assert!(result.is_err());
assert_eq!(*result.unwrap_err(), ParseError::UnexpectedEnd);
}
// Assert that `left` and `right`, when parsed as ES Modules, consist of the
// same sequence of tokens (although possibly at different offsets).
fn assert_same_tokens<'alloc>(left: &str, right: &str) {
let allocator = &Bump::new();
let left_atoms = Rc::new(RefCell::new(SourceAtomSet::new()));
let left_slices = Rc::new(RefCell::new(SourceSliceList::new()));
let right_atoms = Rc::new(RefCell::new(SourceAtomSet::new()));
let right_slices = Rc::new(RefCell::new(SourceSliceList::new()));
let mut left_lexer = Lexer::new(
allocator,
left.chars(),
left_atoms.clone(),
left_slices.clone(),
);
let mut right_lexer = Lexer::new(
allocator,
right.chars(),
right_atoms.clone(),
right_slices.clone(),
);
let mut left_parser = Parser::new(
AstBuilder::new(allocator, left_atoms, left_slices),
generated_parser::START_STATE_MODULE,
);
let mut right_parser = Parser::new(
AstBuilder::new(allocator, right_atoms, right_slices),
generated_parser::START_STATE_MODULE,
);
loop {
let left_token = left_lexer
.next(&left_parser)
.expect("error parsing left string");
let right_token = right_lexer
.next(&right_parser)
.expect("error parsing right string");
assert_eq!(
left_token.terminal_id, right_token.terminal_id,
"at offset {} in {:?} / {} in {:?}",
left_token.loc.start, left, right_token.loc.start, right,
);
assert_eq!(
left_token.value, right_token.value,
"at offsets {} / {}",
left_token.loc.start, right_token.loc.start
);
if left_token.terminal_id == TerminalId::End {
break;
}
left_parser.write_token(left_token).unwrap();
right_parser.write_token(right_token).unwrap();
}
left_parser.close(left_lexer.offset()).unwrap();
right_parser.close(left_lexer.offset()).unwrap();
}
fn assert_can_close_after<'alloc, T: IntoChunks<'alloc>>(code: T) {
let allocator = &Bump::new();
let buf = chunks_to_string(code);
let atoms = Rc::new(RefCell::new(SourceAtomSet::new()));
let slices = Rc::new(RefCell::new(SourceSliceList::new()));
let mut lexer = Lexer::new(allocator, buf.chars(), atoms.clone(), slices.clone());
let mut parser = Parser::new(
AstBuilder::new(allocator, atoms, slices),
generated_parser::START_STATE_SCRIPT,
);
loop {
let t = lexer.next(&parser).expect("lexer error");
if t.terminal_id == TerminalId::End {
break;
}
parser.write_token(t).unwrap();
}
assert!(parser.can_close());
}
fn assert_same_number(code: &str, expected: f64) {
let allocator = &Bump::new();
let script = try_parse(allocator, code).unwrap().unbox();
match &script.statements[0] {
Statement::ExpressionStatement(expression) => match &**expression {
Expression::LiteralNumericExpression(num) => {
assert_eq!(num.value, expected, "{}", code);
}
_ => panic!("expected LiteralNumericExpression"),
},
_ => panic!("expected ExpressionStatement"),
}
}
#[test]
fn test_asi_at_end() {
assert_parses("3 + 4");
assert_syntax_error("3 4");
assert_incomplete("3 +");
assert_incomplete("{");
assert_incomplete("{;");
}
#[test]
fn test_asi_at_block_end() {
assert_parses("{ doCrimes() }");
assert_parses("function f() { ok }");
}
#[test]
fn test_asi_after_line_terminator() {
assert_parses(
"switch (value) {
case 1: break
case 2: console.log('2');
}",
);
assert_syntax_error("switch (value) { case 1: break case 2: console.log('2'); }");
// "[T]he presence or absence of single-line comments does not affect the
// process of automatic semicolon insertion[...]."
assert_parses("x = 1 // line break here\ny = 2");
assert_parses("x = 1 // line break here\r\ny = 2");
assert_parses("x = 1 /* no line break in here */ //\ny = 2");
assert_parses("x = 1<!-- line break here\ny = 2");
assert_syntax_error("x = 1 /* no line break in here */ y = 2");
assert_parses("x = 1 /* line break \n there */y = 2");
}
#[test]
fn test_asi_suppressed() {
// The specification says ASI does not happen in the production
// EmptyStatement : `;`.
// TODO - assert_syntax_error("if (true)");
assert_syntax_error("{ for (;;) }");
// ASI does not happen in for(;;) loops.
assert_syntax_error("for ( \n ; ) {}");
assert_syntax_error("for ( ; \n ) {}");
assert_syntax_error("for ( \n \n ) {}");
assert_syntax_error("for (var i = 0 \n i < 9; i++) {}");
assert_syntax_error("for (var i = 0; i < 9 \n i++) {}");
assert_syntax_error("for (i = 0 \n i < 9; i++) {}");
assert_syntax_error("for (i = 0; i < 9 \n i++) {}");
assert_syntax_error("for (const i = 0 \n i < 9; i++) {}");
// ASI is suppressed in the production ClassElement[Yield, Await] : `;`
// to prevent an infinite loop of ASI. lol
assert_syntax_error("class Fail { \n +1; }");
}
#[test]
fn test_if_else() {
assert_parses("if (x) f();");
assert_incomplete("if (x)");
assert_parses("if (x) f(); else g();");
assert_incomplete("if (x) f(); else");
assert_parses("if (x) if (y) g(); else h();");
assert_parses("if (x) if (y) g(); else h(); else j();");
}
#[test]
fn test_lexer_decimal() {
assert_parses("0.");
assert_parses(".5");
assert_syntax_error(".");
}
#[test]
fn test_numbers() {
assert_same_number("0", 0.0);
assert_same_number("1", 1.0);
assert_same_number("10", 10.0);
assert_error_eq("0a", ParseError::IllegalCharacter('a'));
assert_error_eq("1a", ParseError::IllegalCharacter('a'));
assert_error_eq("1.0a", ParseError::IllegalCharacter('a'));
assert_error_eq(".0a", ParseError::IllegalCharacter('a'));
assert_error_eq("1.a", ParseError::IllegalCharacter('a'));
assert_same_number("1.0", 1.0);
assert_same_number("1.", 1.0);
assert_same_number("0.", 0.0);
assert_same_number("1.0e0", 1.0);
assert_same_number("1.e0", 1.0);
assert_same_number(".0e0", 0.0);
assert_same_number("1.0e+0", 1.0);
assert_same_number("1.e+0", 1.0);
assert_same_number(".0e+0", 0.0);
assert_same_number("1.0e-0", 1.0);
assert_same_number("1.e-0", 1.0);
assert_same_number(".0e-0", 0.0);
assert_error_eq("1.0e", ParseError::UnexpectedEnd);
assert_error_eq("1.e", ParseError::UnexpectedEnd);
assert_error_eq(".0e", ParseError::UnexpectedEnd);
assert_error_eq("1.0e+", ParseError::UnexpectedEnd);
assert_error_eq("1.0e-", ParseError::UnexpectedEnd);
assert_error_eq(".0e+", ParseError::UnexpectedEnd);
assert_error_eq(".0e-", ParseError::UnexpectedEnd);
assert_same_number("1.0E0", 1.0);
assert_same_number("1.E0", 1.0);
assert_same_number(".0E0", 0.0);
assert_same_number("1.0E+0", 1.0);
assert_same_number("1.E+0", 1.0);
assert_same_number(".0E+0", 0.0);
assert_same_number("1.0E-0", 1.0);
assert_same_number("1.E-0", 1.0);
assert_same_number(".0E-0", 0.0);
assert_error_eq("1.0E", ParseError::UnexpectedEnd);
assert_error_eq("1.E", ParseError::UnexpectedEnd);
assert_error_eq(".0E", ParseError::UnexpectedEnd);
assert_error_eq("1.0E+", ParseError::UnexpectedEnd);
assert_error_eq("1.0E-", ParseError::UnexpectedEnd);
assert_error_eq(".0E+", ParseError::UnexpectedEnd);
assert_error_eq(".0E-", ParseError::UnexpectedEnd);
assert_same_number(".0", 0.0);
assert_parses("");
assert_same_number("0b0", 0.0);
assert_same_number("0b1", 1.0);
assert_same_number("0B01", 1.0);
assert_error_eq("0b", ParseError::UnexpectedEnd);
assert_error_eq("0b ", ParseError::IllegalCharacter(' '));
assert_error_eq("0b2", ParseError::IllegalCharacter('2'));
assert_same_number("0o0", 0.0);
assert_same_number("0o7", 7.0);
assert_same_number("0O01234567", 0o01234567 as f64);
assert_error_eq("0o", ParseError::UnexpectedEnd);
assert_error_eq("0o ", ParseError::IllegalCharacter(' '));
assert_error_eq("0o8", ParseError::IllegalCharacter('8'));
assert_same_number("0x0", 0.0);
assert_same_number("0xf", 15.0);
assert_not_implemented("0X0123456789abcdef");
assert_not_implemented("0X0123456789ABCDEF");
assert_error_eq("0x", ParseError::UnexpectedEnd);
assert_error_eq("0x ", ParseError::IllegalCharacter(' '));
assert_error_eq("0xg", ParseError::IllegalCharacter('g'));
assert_parses("1..x");
assert_same_number("1_1", 11.0);
assert_same_number("0b1_1", 3.0);
assert_same_number("0o1_1", 9.0);
assert_same_number("0x1_1", 17.0);
assert_same_number("1_1.1_1", 11.11);
assert_same_number("1_1.1_1e+1_1", 11.11e11);
assert_error_eq("1_", ParseError::UnexpectedEnd);
assert_error_eq("1._1", ParseError::IllegalCharacter('_'));
assert_error_eq("1.1_", ParseError::UnexpectedEnd);
assert_error_eq("1.1e1_", ParseError::UnexpectedEnd);
assert_error_eq("1.1e_1", ParseError::IllegalCharacter('_'));
}
#[test]
fn test_numbers_large() {
assert_same_number("4294967295", 4294967295.0);
assert_same_number("4294967296", 4294967296.0);
assert_same_number("4294967297", 4294967297.0);
assert_same_number("9007199254740991", 9007199254740991.0);
assert_same_number("9007199254740992", 9007199254740992.0);
assert_same_number("9007199254740993", 9007199254740992.0);
assert_same_number("18446744073709553664", 18446744073709552000.0);
assert_same_number("18446744073709553665", 18446744073709556000.0);
assert_same_number("0b11111111111111111111111111111111", 4294967295.0);
assert_same_number("0b100000000000000000000000000000000", 4294967296.0);
assert_same_number("0b100000000000000000000000000000001", 4294967297.0);
assert_same_number(
"0b11111111111111111111111111111111111111111111111111111",
9007199254740991.0,
);
assert_not_implemented("0b100000000000000000000000000000000000000000000000000000");
assert_same_number("0o77777777777777777", 2251799813685247.0);
assert_not_implemented("0o100000000000000000");
assert_same_number("0xfffffffffffff", 4503599627370495.0);
assert_not_implemented("0x10000000000000");
assert_same_number("4.9406564584124654417656879286822e-324", 5e-324);
}
#[test]
fn test_bigint() {
assert_not_implemented("0n");
/*
assert_parses("0n");
assert_parses("1n");
assert_parses("10n");
assert_error_eq("0na", ParseError::IllegalCharacter('a'));
assert_error_eq("1na", ParseError::IllegalCharacter('a'));
assert_error_eq("1.0n", ParseError::IllegalCharacter('n'));
assert_error_eq(".0n", ParseError::IllegalCharacter('n'));
assert_error_eq("1.n", ParseError::IllegalCharacter('n'));
assert_error_eq("1e0n", ParseError::IllegalCharacter('n'));
assert_error_eq("1e+0n", ParseError::IllegalCharacter('n'));
assert_error_eq("1e-0n", ParseError::IllegalCharacter('n'));
assert_error_eq("1E0n", ParseError::IllegalCharacter('n'));
assert_error_eq("1E+0n", ParseError::IllegalCharacter('n'));
assert_error_eq("1E-0n", ParseError::IllegalCharacter('n'));
assert_parses("0b0n");
assert_parses("0b1n");
assert_parses("0B01n");
assert_error_eq("0bn", ParseError::IllegalCharacter('n'));
assert_parses("0o0n");
assert_parses("0o7n");
assert_parses("0O01234567n");
assert_error_eq("0on", ParseError::IllegalCharacter('n'));
assert_parses("0x0n");
assert_parses("0xfn");
assert_parses("0X0123456789abcdefn");
assert_parses("0X0123456789ABCDEFn");
assert_error_eq("0xn", ParseError::IllegalCharacter('n'));
assert_parses("1_1n");
assert_parses("0b1_1n");
assert_parses("0o1_1n");
assert_parses("0x1_1n");
assert_error_eq("1_1.1_1n", ParseError::IllegalCharacter('n'));
assert_error_eq("1_1.1_1e1_1n", ParseError::IllegalCharacter('n'));
assert_error_eq("1_n", ParseError::IllegalCharacter('n'));
assert_error_eq("1.1_n", ParseError::IllegalCharacter('n'));
assert_error_eq("1.1e1_n", ParseError::IllegalCharacter('n'));
*/
}
#[test]
fn test_arrow() {
assert_parses("x => x");
assert_parses("f = x => x;");
assert_parses("(x, y) => [y, x]");
assert_parses("f = (x, y) => {}");
assert_syntax_error("(x, y) => {x: x, y: y}");
}
#[test]
fn test_illegal_character() {
assert_illegal_character("\0");
assert_illegal_character("—x;");
assert_illegal_character("const ONE_THIRD = 1 ÷ 3;");
}
#[test]
fn test_identifier() {
// U+00B7 MIDDLE DOT is an IdentifierPart.
assert_parses("_·_ = {_·_:'·_·'};");
// <ZWJ> and <ZWNJ> match IdentifierPart but not IdentifierStart.
assert_parses("var x\u{200c};"); // <ZWNJ>
assert_parses("_\u{200d}();"); // <ZWJ>
assert_parses("_\u{200d}__();"); // <ZWJ>
assert_parses("_\u{200d}\u{200c}();"); // <ZWJ>
assert_illegal_character("var \u{200c};"); // <ZWNJ>
assert_illegal_character("x = \u{200d};"); // <ZWJ>
// Other_ID_Start for backward compat.
assert_parses("\u{309B}();");
assert_parses("\u{309C}();");
assert_parses("_\u{309B}();");
assert_parses("_\u{309C}();");
// Non-BMP.
assert_parses("\u{10000}();");
assert_parses("_\u{10000}();");
assert_illegal_character("\u{1000c}();");
assert_illegal_character("_\u{1000c}();");
}
#[test]
fn test_regexp() {
assert_parses(r"/\w/");
assert_parses("/[A-Z]/");
assert_parses("/[//]/");
assert_parses("/a*a/");
assert_parses("/**//x*/");
assert_same_tokens("/**//x*/", "/x*/");
assert_parses("{} /x/");
assert_parses("of / 2");
}
#[test]
fn test_html_comments() {
assert_same_tokens("x<!--y;", "x");
assert_same_tokens("x<!-y;", "x < ! - y ;");
assert_same_tokens("x<!y", "x < ! y");
assert_same_tokens("--> hello world\nok", "ok");
assert_same_tokens("/* ignore */ --> also ignore\nok", "ok");
assert_same_tokens("/* ignore *//**/--> also ignore\nok", "ok");
assert_same_tokens("x-->y\nz", "x -- > y\nz");
}
#[test]
fn test_incomplete_comments() {
assert_error("/*");
assert_error("/* hello world");
assert_error("/* hello world *");
assert_parses(&vec!["/* hello\n", " world */"]);
assert_parses(&vec!["// oawfeoiawj", "ioawefoawjie"]);
assert_parses(&vec!["// oawfeoiawj", "ioawefoawjie\n ok();"]);
assert_parses(&vec!["// oawfeoiawj", "ioawefoawjie", "jiowaeawojefiw"]);
assert_parses(&vec![
"// oawfeoiawj",
"ioawefoawjie",
"jiowaeawojefiw\n ok();",
]);
}
#[test]
fn test_strings() {
assert_parses("f(\"\",\"\")");
assert_parses("f(\"\")");
assert_parses("(\"\")");
assert_parses("f('','')");
assert_parses("f('')");
assert_parses("('')");
}
#[test]
fn test_awkward_chunks() {
assert_parses(&vec!["const", "ructor.length = 1;"]);
assert_parses(&vec!["const", " x = 1;"]);
// Try feeding one character at a time to the parser.
let chars: Vec<&str> = "function f() { ok(); }".split("").collect();
assert_parses(&chars);
// XXX TODO
//assertEqual(
// self.parse(&vec!["/xyzzy/", "g;"]),
// ('Script',
// ('ScriptBody',
// ('StatementList 0',
// ('ExpressionStatement',
// ('PrimaryExpression 10', '/xyzzy/g'))))));
let allocator = &Bump::new();
let actual = try_parse(allocator, &vec!["x/", "=2;"]).unwrap();
let atoms = Rc::new(RefCell::new(SourceAtomSet::new()));
let expected = Script {
directives: arena::Vec::new_in(allocator),
statements: bumpalo::vec![
in allocator;
Statement::ExpressionStatement(arena::alloc(
allocator,
Expression::CompoundAssignmentExpression {
operator: CompoundAssignmentOperator::Div {
loc: SourceLocation::new(1, 3),
},
binding: SimpleAssignmentTarget::AssignmentTargetIdentifier(
AssignmentTargetIdentifier {
name: Identifier {
value: atoms.borrow_mut().insert("x"),
loc: SourceLocation::new(0, 1),
},
loc: SourceLocation::new(0, 1),
},
),
expression: arena::alloc(
allocator,
Expression::LiteralNumericExpression(NumericLiteral {
value: 2.0,
loc: SourceLocation::new(3, 4),
}),
),
loc: SourceLocation::new(0, 4),
},
))
],
loc: SourceLocation::new(0, 4),
};
assert_eq!(format!("{:?}", actual), format!("{:?}", expected));
}
#[test]
fn test_can_close() {
let empty: Vec<&str> = vec![];
assert_can_close_after(&empty);
assert_can_close_after("");
assert_can_close_after("2 + 2;\n");
assert_can_close_after("// seems ok\n");
}
#[test]
fn test_regex() {
assert_parses("/x/");
assert_parses("x = /x/");
assert_parses("x = /x/g");
// FIXME: Unexpected flag
// assert_parses("x = /x/wow_flags_can_be_$$anything$$");
assert_not_implemented("x = /x/wow_flags_can_be_$$anything$$");
// TODO: Should the lexer running out of input throw an incomplete error, or a lexer error?
assert_error_eq("/x", ParseError::UnterminatedRegExp);
assert_incomplete("x = //"); // comment
assert_error_eq("x = /*/", ParseError::UnterminatedMultiLineComment); /*/ comment */
assert_error_eq("x =/= 2", ParseError::UnterminatedRegExp);
assert_parses("x /= 2");
assert_parses("x = /[]/");
assert_parses("x = /[^x]/");
assert_parses("x = /+=351*/");
assert_parses("x = /^\\s*function (\\w+)/;");
assert_parses("const regexp = /this is fine: [/] dont @ me/;");
}
#[test]
fn test_arrow_parameters() {
assert_error_eq(
"({a:a, ...b, c:c}) => {}",
ParseError::ObjectPatternWithNonFinalRest,
);
assert_error_eq(
"(a, [...zero, one]) => {}",
ParseError::ArrayPatternWithNonFinalRest,
);
assert_error_eq(
"(a, {items: [...zero, one]}) => {}",
ParseError::ArrayPatternWithNonFinalRest,
);
}
#[test]
fn test_invalid_assignment_targets() {
assert_syntax_error("2 + 2 = x;");
assert_error_eq("(2 + 2) = x;", ParseError::InvalidAssignmentTarget);
assert_error_eq("++-x;", ParseError::InvalidAssignmentTarget);
assert_error_eq("(x && y)--;", ParseError::InvalidAssignmentTarget);
}
#[test]
fn test_can_close_with_asi() {
assert_can_close_after("2 + 2\n");
}
#[test]
fn test_conditional_keywords() {
// property names
assert_parses("const obj = {if: 3, function: 4};");
assert_parses("const obj = {true: 1, false: 0, null: NaN};");
assert_parses("assert(obj.if == 3);");
assert_parses("assert(obj.true + obj.false + obj.null == NaN);");
// method names
assert_parses(
"
class C {
if() {}
function() {}
}
",
);
// FIXME: let (multitoken lookahead):
assert_not_implemented("let a = 1;");
/*
// let as identifier
assert_parses("var let = [new Date];");
// let as keyword, then identifier
assert_parses("let v = let;");
// `let .` -> ExpressionStatement
assert_parses("let.length;");
// `let [` -> LexicalDeclaration
assert_syntax_error("let[0].getYear();");
*/
assert_parses(
"
var of = [1, 2, 3];
for (of of of) console.log(of); // logs 1, 2, 3
",
);
// Not implemented:
// assert_parses("var of, let, private, target;");
assert_parses("class X { get y() {} }");
// Not implemented:
// assert_parses("async: { break async; }");
assert_parses("var get = { get get() {}, set get(v) {}, set: 3 };");
// Not implemented (requires hack; grammar is not LR(1)):
// assert_parses("for (async of => {};;) {}");
// assert_parses("for (async of []) {}");
}
#[test]
fn test_async_arrows() {
// FIXME: async (multiple lookahead)
assert_not_implemented("const a = async a => 1;");
/*
assert_parses("let f = async arg => body;");
assert_parses("f = async (a1, a2) => {};");
assert_parses("f = async (a1 = b + c, ...a2) => {};");
assert_error_eq("f = async (a, b + c) => {};", ParseError::InvalidParameter);
assert_error_eq(
"f = async (...a1, a2) => {};",
ParseError::ArrowParametersWithNonFinalRest,
);
assert_error_eq("obj.async() => {}", ParseError::ArrowHeadInvalid);
*/
assert_error_eq("foo(a, b) => {}", ParseError::ArrowHeadInvalid);
}
#[test]
fn test_binary() {
assert_parses("1 == 2");
assert_parses("1 != 2");
assert_parses("1 === 2");
assert_parses("1 !== 2");
assert_parses("1 < 2");
assert_parses("1 <= 2");
assert_parses("1 > 2");
assert_parses("1 >= 2");
assert_parses("1 in 2");
assert_parses("1 instanceof 2");
assert_parses("1 << 2");
assert_parses("1 >> 2");
assert_parses("1 >>> 2");
assert_parses("1 + 2");
assert_parses("1 - 2");
assert_parses("1 * 2");
assert_parses("1 / 2");
assert_parses("1 % 2");
assert_parses("1 ** 2");
assert_parses("1 , 2");
assert_parses("1 || 2");
assert_parses("1 && 2");
assert_parses("1 | 2");
assert_parses("1 ^ 2");
assert_parses("1 & 2");
}
#[test]
fn test_coalesce() {
assert_parses("const f = options.prop ?? 0;");
assert_syntax_error("if (options.prop ?? 0 || options.prop > 1000) {}");
}
#[test]
fn test_no_line_terminator_here() {
// Parse `code` as a Script and compute some function of the resulting AST.
fn parse_then<F, R>(code: &str, f: F) -> R
where
F: FnOnce(&Script) -> R,
{
let allocator = &Bump::new();
match try_parse(allocator, code) {
Err(err) => {
panic!("Failed to parse code {:?}: {}", code, err);
}
Ok(script) => f(&*script),
}
}
// Parse `code` as a Script and return the number of top-level
// StatementListItems.
fn count_items(code: &str) -> usize {
parse_then(code, |script| script.statements.len())
}
// Without a newline, labelled `break` in loop. But a line break changes
// the meaning -- then it's a plain `break` statement, followed by
// ExpressionStatement `LOOP;`
assert_eq!(count_items("LOOP: while (true) break LOOP;"), 1);
assert_eq!(count_items("LOOP: while (true) break \n LOOP;"), 2);
// The same, but for `continue`.
assert_eq!(count_items("LOOP: while (true) continue LOOP;"), 1);
assert_eq!(count_items("LOOP: while (true) continue \n LOOP;"), 2);
// Parse `code` as a Script, expected to contain a single function
// declaration, and return the number of statements in the function body.
fn count_statements_in_function(code: &str) -> usize {
parse_then(code, |script| {
assert_eq!(
script.statements.len(),
1,
"expected function declaration, got {:?}",
script
);
match &script.statements[0] {
Statement::FunctionDeclaration(func) => func.body.statements.len(),
_ => panic!("expected function declaration, got {:?}", script),
}
})
}
assert_eq!(
count_statements_in_function("function f() { return x; }"),
1
);
assert_eq!(
count_statements_in_function("function f() { return\n x; }"),
2
);
assert_parses("x++");
assert_incomplete("x\n++");
assert_parses("throw fit;");
assert_syntax_error("throw\nfit;");
// Alternative ways of spelling LineTerminator
assert_syntax_error("throw//\nfit;");
assert_syntax_error("throw/*\n*/fit;");
assert_syntax_error("throw\rfit;");
assert_syntax_error("throw\r\nfit;");
}