LibJS: Add new host hook, specify template literals and more #14904
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
davidot
force-pushed
the
plz-no-privates-on-my-window
branch
from
e863fc3 to
ecfdd4a
Compare
linusg
reviewed
Aug 17, 2022
This hook allows us to reject private elements on certain exotic objects like the window object in browser. Note that per the spec we should only call this hook if the host is a web browser, however because LibJS has no way of knowing whether it is in a web browser environment we just always call the host hook.
Assuming we had at least one argument meant that the ...arg count would underflow causing the bound function to have length 0 instead of the given length when binding with no arguments.
We use strtod to convert a string to number after checking whether the string is [+-]Infinity, however strtod also checks for either 'inf' or 'infinity' in a case-insensitive. There are still valid cases for strtod to return infinity like 10e100000 so we just check if the "number" contains 'i' or 'I' in which case the strtod infinity is not valid.
Since tagged template literals can inspect the raw string it is not a syntax error to have invalid escapes. However the cooked value should be `undefined`. We accomplish this by tracking whether parse_string_literal fails and then using a NullLiteral (since UndefinedLiteral is not a thing) and finally converting null in tagged template execution to undefined.
We cache on the AST node side as this is easier to track a position, we just have to take care to wrap the values in a handle to make sure they are not garbage collected.
davidot
force-pushed
the
plz-no-privates-on-my-window
branch
from
ecfdd4a to
fe0082d
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
I have not implemented the hook in browser yet as the PR is not merged yet:
whatwg/html#8198
I do have a patch ready but it might be more complicated by extending location and or window
The original JS PR has already been merged:
tc39/ecma262#2807