diff options
Diffstat (limited to 'dhall_syntax/src/parser.rs')
| -rw-r--r-- | dhall_syntax/src/parser.rs | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/dhall_syntax/src/parser.rs b/dhall_syntax/src/parser.rs index 5be8477..8336c74 100644 --- a/dhall_syntax/src/parser.rs +++ b/dhall_syntax/src/parser.rs @@ -425,8 +425,27 @@ make_parser! { // `s` has length 8, so `bytes` has length 4 let bytes: &[u8] = &hex::decode(s).unwrap(); - let c = u32::from_be_bytes(bytes.try_into().unwrap()); - let c = char::try_from(c).unwrap(); + let i = u32::from_be_bytes(bytes.try_into().unwrap()); + let c = char::try_from(i).unwrap(); + match i { + 0xD800..=0xDFFF => { + let c_ecapsed = c.escape_unicode(); + Err(format!("Escape sequences can't contain surrogate pairs: \"{}\"", c_ecapsed))? + }, + 0x0FFFE..=0x0FFFF | 0x1FFFE..=0x1FFFF | + 0x2FFFE..=0x2FFFF | 0x3FFFE..=0x3FFFF | + 0x4FFFE..=0x4FFFF | 0x5FFFE..=0x5FFFF | + 0x6FFFE..=0x6FFFF | 0x7FFFE..=0x7FFFF | + 0x8FFFE..=0x8FFFF | 0x9FFFE..=0x9FFFF | + 0xAFFFE..=0xAFFFF | 0xBFFFE..=0xBFFFF | + 0xCFFFE..=0xCFFFF | 0xDFFFE..=0xDFFFF | + 0xEFFFE..=0xEFFFF | 0xFFFFE..=0xFFFFF | + 0x10FFFE..=0x10FFFF => { + let c_ecapsed = c.escape_unicode(); + Err(format!("Escape sequences can't contain non-characters: \"{}\"", c_ecapsed))? + }, + _ => {} + } std::iter::once(c).collect() } } |