Add validator for byte

crates/ra_syntax/src/yellow/syntax_error.rs

@@ -72,6 +72,16 @@ pub enum SyntaxErrorKind {
     EmptyChar,
     UnclosedChar,
     OverlongChar,
+    EmptyByte,
+    UnclosedByte,
+    OverlongByte,
+    ByteOutOfRange,
+    UnescapedByte,
+    EmptyByteEscape,
+    InvalidByteEscape,
+    TooShortByteCodeEscape,
+    MalformedByteCodeEscape,
+    UnicodeEscapeForbidden,
     EmptyAsciiEscape,
     InvalidAsciiEscape,
     TooShortAsciiCodeEscape,
@@ -98,6 +108,16 @@ impl fmt::Display for SyntaxErrorKind {
             EmptyChar => write!(f, "Empty char literal"),
             UnclosedChar => write!(f, "Unclosed char literal"),
             OverlongChar => write!(f, "Char literal should be one character long"),
+            EmptyByte => write!(f, "Empty byte literal"),
+            UnclosedByte => write!(f, "Unclosed byte literal"),
+            OverlongByte => write!(f, "Byte literal should be one character long"),
+            ByteOutOfRange => write!(f, "Byte should be a valid ASCII character"),
+            UnescapedByte => write!(f, "This byte should always be escaped"),
+            EmptyByteEscape => write!(f, "Empty escape sequence"),
+            InvalidByteEscape => write!(f, "Invalid escape sequence"),
+            TooShortByteCodeEscape => write!(f, "Escape sequence should have two digits"),
+            MalformedByteCodeEscape => write!(f, "Escape sequence should be a hexadecimal number"),
+            UnicodeEscapeForbidden => write!(f, "Unicode escapes are not allowed in byte literals or byte strings"),
             TooShortAsciiCodeEscape => write!(f, "Escape sequence should have two digits"),
             AsciiCodeEscapeOutOfRange => {
                 write!(f, "Escape sequence should be between \\x00 and \\x7F")