strange behavior when a unicode escape has more than 6 hex digits

[windrunner414]

I think this should be a compile-time error.

[windrunner414]

try print("\u{0000410BC");, and will print АBC.

[jensjoha]

https://github.com/dart-lang/language/blob/e9ffb51071277b044a3e4ec2c4fc576f68b0acea/specification/dartLangSpec.tex#L9033-L9040

https://github.com/dart-lang/language/blob/e9ffb51071277b044a3e4ec2c4fc576f68b0acea/specification/dartLangSpec.tex#L8689-L8691

https://github.com/dart-lang/language/blob/e9ffb51071277b044a3e4ec2c4fc576f68b0acea/specification/dartLangSpec.tex#L16588

<ESCAPE_SEQUENCE> ::= ‘\n’ | ‘\r’ | ‘\f’ | ‘\b’ | ‘\t’ | ‘\v’
| ‘\x’ <HEX_DIGIT> <HEX_DIGIT>
| ‘\u’ <HEX_DIGIT> <HEX_DIGIT> <HEX_DIGIT> <HEX_DIGIT>
| ‘\u{’ <HEX_DIGIT_SEQUENCE> ‘}’

<HEX_DIGIT_SEQUENCE> ::= <HEX_DIGIT> <HEX_DIGIT>? <HEX_DIGIT>? <HEX_DIGIT>? <HEX_DIGIT>? <HEX_DIGIT>?

<HEX_DIGIT> ::= `a' .. `f'
  | `A' .. `F'
  | <DIGIT>

<DIGIT> ::= `0' .. `9'

So yeah, anything more than 6 hex digits should be a compile time error.

[jensjoha]

This was fixed in fd4e41a.