Missing error for keywords with escaped characters

[ajafff]

TypeScript Version: 3.6.0-dev.20190804

Search Terms:

Code

v\u0061r a = 1;
// parses as: 'var a = 1;'

Expected behavior:
Keyword must not contain escaped characters

Actual behavior:
No parse/compile error. Instead Chrome gives Uncaught SyntaxError: Keyword must not contain escaped characters

Playground Link: doesn't use the correct version yet

Related Issues:
#32096 made parsing the above code possible. cc @weswigham

[weswigham]

Hah, neat. I guess we need a dedicated error for this now.

[RyanCavanaugh]

😅

[weswigham]

So we apparently already had a test for this - scannerUnicodeEscapeInKeyword1.ts - which has existed since the compiler was uploaded to github. It just has the wrong behavior.