From the spec: https://tc39.es/ecma262/#sec-literals-numeric-literals
The SourceCharacter immediately following a NumericLiteral must not be
an IdentifierStart or DecimalDigit.
For example: 3in is an error and not the two input elements 3 and in.
Otherwise we crash the interpreter when an exception is thrown during
evaluation of the while or do/while test expression - which is easily
caused by a ReferenceError - e.g.:
while (someUndefinedVariable) {
// ...
}
If there's a newline between the closing paren and arrow it's not a
valid arrow function, ASI should kick in instead (it'll then fail with
"Unexpected token Arrow")
This simplifies try_parse_arrow_function_expression() and fixes a few
cases that should not produce an arrow function AST but did:
(a,,) => {}
(a b) => {}
(a ...b) => {}
(...b a) => {}
The new parsing logic checks whether parens are expected and uses
parse_function_parameters() if so, rolling back if a new syntax error
occurs during that. Otherwise it's just an identifier in which case we
parse the single parameter ourselves.
When changing the attributes of an existing property of an object with
unique shape we must not change the PropertyMetadata offset.
Doing so without resizing the underlying storage vector caused an OOB
write crash.
Fixes#3735.
Previously, when a loop detected an unwind of type ScopeType::Function
(which means a return statement was executed inside of the loop), it
would just return undefined. This set the VM's last_value to undefined,
when it should have been the returned value. This patch makes all loop
statements return the appropriate value in the above case.
'continue' is no longer allowed outside of a loop, and an unlabeled
'break' is not longer allowed outside of a loop or switch statement.
Labeled 'break' statements are still allowed everywhere, even if the
label does not exist.
The check for invalid lhs and assignment to eval/arguments in strict
mode should happen for all kinds of assignment expressions, not just
AssignmentOp::Assignment.
Since blocks can't be strict by themselves, it makes no sense for them
to store whether or not they are strict. Strict-ness is now stored in
the Program and FunctionNode ASTNodes. Fixes issue #3641
In the case of an exception in a property getter function we would not
return early, and a subsequent attempt to call the replacer function
would crash the interpreter due to call_internal() asserting.
Fixes#3548.
This fixes two cases obj[expr] and obj[expr]() (MemberExpression and
CallExpression respectively) when expr throws an exception and results
in an empty value, causing a crash by passing the invalid PropertyName
created by computed_property_name() to Object::get() without checking it
first.
Fixes#3459.
This fixes two issues with running a TryStatement finalizer:
- Temporarily store and clear the exception, if any, so we can run the
finalizer block statement without it getting in our way, which could
have unexpected side effects otherwise (and will likely return early
somewhere).
- Stop unwinding so more than one child node of the finalizer
BlockStatement is executed if an exception has been thrown previously
(which would have called unwind(ScopeType::Try)). Re-throwing as
described above ensures we still unwind after the finalizer, if
necessary.
Also add some tests specifically for try/catch/finally blocks, we
didn't have any!
Interpreter::run() was so far being used both as the "public API entry
point" for running a JS::Program as well as internally to execute
JS::Statement|s of all kinds - this is now more distinctly separated.
A program as returned by the parser is still going through run(), which
is responsible for creating the initial global call frame, but all other
statements are executed via execute_statement() directly.
Fixes#3437, a regression introduced by adding ASSERT(!exception()) to
run() without considering the effects that would have on internal usage.
Test files created with:
$ for f in Libraries/LibJS/Tests/builtins/Date/Date.prototype.get*js; do
cp $f $(echo $f | sed -e 's/get/getUTC/') ;
done
$ rm Libraries/LibJS/Tests/builtins/Date/Date.prototype.getUTCTime.js
$ git add Libraries/LibJS/Tests/builtins/Date/Date.prototype.getUTC*.js
$ ls Libraries/LibJS/Tests/builtins/Date/Date.prototype.getUTC*.js | \
xargs sed -i -e 's/get/getUTC/g'
Year computation has to be based on seconds, not days, in case
t is < 0 but t / __seconds_per_day is 0.
Year computation also has to consider negative timestamps.
With this, days is always positive and <= the number of days in the
year, so base the tm_wday computation directly on the timestamp,
and do it first, before t is modified in the year computation.
In C, % can return a negative number if the left operand is negative,
compensate for that.
Tested via test-js. (Except for tm_wday, since we don't implement
Date.prototype.getUTCDate() yet.)
LibJS doesn't store stacks for exception objects, so this
only amends test-common.js's __expect() with an optional
`details` function that can produce a more detailed error
message, and it lets test-js.cpp read and print that
error message. I added the optional details parameter to
a few matchers, most notably toBe() where it now prints
expected and actual value.
It'd be nice to have line numbers of failures, but that
seems hard to do with the current design, and this is already
much better than the current state.
The constructor with a string argument isn't implemented yet, but
this implements the other variants.
The timestamp constructor doens't handle negative timestamps correctly.
Out-of-bound and invalid arguments aren't handled correctly.
The optional 2nd and 3rd arguments are not yet implemented.
This assumes that `this` is the Array constructor and doesn't yet
implement the more general behavior in the ES6 spec that allows
transferring this method to other constructors.
With this, typing `"\xff"` into Browser's console no longer
makes the app crash.
While here, also make the \u handler call append_codepoint()
instead of calling an overload where it's not immediately clear
which overload is getting called. This has no behavior change.
It's broken for strings with characters outside 7-bit ASCII, but
it's broken in the same way as several existing functions (e.g.
charAt()), so that's probably ok for now.
Finally use Symbol.iterator protocol in language features :) currently
only used in for-of loops and spread expressions, but will have more
uses later (Maps, Sets, Array.from, etc).
With the addition of symbol keys, work can now be done on starting to
implement the well-known symbol functionality. The most important of
these well-known symbols is by far Symbol.iterator.
This patch adds IteratorPrototype, as well as ArrayIterator and
ArrayIteratorPrototype. In the future, sometime after StringIterator has
also been added, this will allow us to use Symbol.iterator directly in
for..of loops, enabling the use of custom iterator objects. Also makes
adding iterator support to native objects much easier (as will have to
be done for Map and Set, when they get added).
Skipped tests count as a "pass" rather than a "fail" (i.e. a test suite
with a skipped test will pass), however it does display a message when
the test is printing.
This is intended for tests which _should_ work, but currently do not.
This should be preferred over "// FIXME" notes if possible.
This commit also exposes JSONObject's implementation of stringify to the
public, so that it can be used by test-js without having to go through
the interpreter's environment.
This moves most of the work from run-tests.sh to test-js.cpp. This way,
we have a lot more control over how the test suite runs, as well as how
it outputs. This should result in some cool functionality!
This commit also refactors test-common.js to mimic the jest library.
This should allow tests to be much more expressive :)
- Use emojis instead of the pass/fail text
- Fix the new version of the script to run inside Serenity
- Don't print erroneous output after 'Output:'; start on a newline
instead
- Skip 'run-tests.sh' while testing
literal methods; add EnvrionmentRecord fields and methods to
LexicalEnvironment
Adding EnvrionmentRecord's fields and methods lets us throw an exception
when |this| is not initialized, which occurs when the super constructor
in a derived class has not yet been called, or when |this| has already
been initialized (the super constructor was already called).
Previously, debugging a test with console.log statements was impossible,
because it would just cause the test to fail with no additional output.
Now, if the output of a test is not "PASS", the output will be printed
under the line where the test failed.
Empty output will have a special message attached to it -- useful when
a test author has forgotten to include `console.log("PASS")` at the end
of a test.
Includes all traps except the following: [[Call]], [[Construct]],
[[OwnPropertyKeys]].
An important implication of this commit is that any call to any virtual
Object method has the potential to throw an exception. These methods
were not checked in this commit -- a future commit will have to protect
these various method calls throughout the codebase.
This patch adds function declaration hoisting. The mechanism
is similar to var hoisting. Hoisted function declarations are to be put
before the hoisted var declarations, hence they have to be treated
separately.
Object::set_prototype() now returns a boolean indicating success.
Setting the prototype to an identical object is always considered
successful, even if the object is non-extensible.
This rewrite drastically increases the accuracy of object literals.
Additionally, an "assertIsSyntaxError" function has been added to
test-common.js to assist in testing syntax errors.
The parser was chomping on commas present after the arrow function expression. eg. [x=>x,2] would parse as [x=>(x,2)] instead of [(x=>x),2].
This is not the case anymore. I've added a small test to prove this.
Previously, the relational operators where casting any value to double
and comparing the results according to C++ semantics.
This patch makes the relational operators in JS behave according to the
standard specification.
Since we don't have BigInt yet, the implementation doesn't take it into
account.
Moved PreferredType from Object to Value. Value::to_primitive now
passes preferred_type to Object::to_primitive.
Adds the ability for a scope (either a function or the entire program)
to be in strict mode. Scopes default to non-strict mode.
There are two ways to determine the strict-ness of the JS engine:
1. In the parser, this can be accessed with the parser_state variable
m_is_strict_mode boolean. If true, the Parser is currently parsing in
strict mode. This is done so that the Parser can generate syntax
errors at parse time, which is required in some cases.
2. With Interpreter.is_strict_mode(). This allows strict mode checking
at runtime as opposed to compile time.
Additionally, in order to test this, a global isStrictMode() function
has been added to the JS ReplObject under the test-mode flag.
This patch adds an IndexedProperties object for storing indexed
properties within an Object. This accomplishes two goals: indexed
properties now have an associated descriptor, and objects now gracefully
handle sparse properties.
The IndexedProperties class is a wrapper around two other classes, one
for simple indexed properties storage, and one for general indexed
property storage. Simple indexed property storage is the common-case,
and is simply a vector of properties which all have attributes of
default_attributes (writable, enumerable, and configurable).
General indexed property storage is for a collection of indexed
properties where EITHER one or more properties have attributes other
than default_attributes OR there is a property with a large index (in
particular, large is '200' or higher).
Indexed properties are now treated relatively the same as storage within
the various Object methods. Additionally, there is a custom iterator
class for IndexedProperties which makes iteration easy. The iterator
skips empty values by default, but can be configured otherwise.
Likewise, it evaluates getters by default, but can be set not to.
This patch adds `Array.prototype.reduceRight()` method to LibJS Runtime. The implementation is (to my best knowledge) conformant to https://tc39.es/ecma262/#sec-array.prototype.reduceright.
Short test in `LibJS/Tests/Array.prototype-generic-functions.js` demonstrates that the function can be applied to other objects besides `Array`.
This patch adds `Array.prototype.reduce()` method to LibJS Runtime.
The implementation is (to my best knowledge) comformant to ECMA262.
The test `Array.prototype-generic-functions.js` demonstrates that the
function can be applied to other objects besides `Array`.
Let's treat it as zero like the ECMAScript spec does in toInteger().
That way we can use to_i32() and don't have to care about weird input
input values where a number is expected, i.e.
"foo".charAt() === "f"
"foo".charAt("bar") === "f"
"foo".charAt(0) === "f"
This patch adds a GetterSetterPair object. Values can now store pointers
to objects of this type. These objects are created when using
Object.defineProperty and providing an accessor descriptor.
