Check Script read names with Rust's alphabetic and alphanumeric tests, so it
split names at U+2118, U+203F, U+00B7 and the zero width non-joiner and joiner,
and took U+00B2 and U+2E2F into names. It now uses the Unicode 16.0 ID_Start
and ID_Continue rule that vectorcraft-js uses, with `$` and `_`
(https://www.unicode.org/reports/tr31/,
https://tc39.es/ecma262/#sec-names-and-keywords).
A `\uXXXX` escape is part of a name only when it stands for a character the
name may hold where it is: `\u0030abc` no longer becomes `0abc`, and malformed
escapes end the name.
The engine's lexer comparison test now checks that both crates take the same
characters into names, written out and as escapes.
New crate vectorcraft-js reads ECMAScript 5.1 source into a syntax tree
with source positions: a UTF-16 lexer (line and column tracking, automatic
semicolon insertion, the regexp and division goals), preprocessor lines
read as directive tokens, a recursive-descent parser to an arena tree, and
the ES5 early errors, strict mode included. Nesting deeper than
Options::max_depth (200 by default) gives a SyntaxError with its line and
column rather than overflowing the stack. Nothing runs scripts yet.
cargo xtask test262 downloads test262 at a pinned commit, checks its
SHA-256, unpacks it into the gitignored corpus/ folder and runs the ES5
syntax tests. A differential test in the engine compares the lexer with
scriptcheck on line counts, directives and unterminated literals.
dotCooCoo