removed check for null characters in literal function

imap-proto/src/parser/core.rs

@@ -98,22 +98,9 @@ pub fn literal(input: &[u8]) -> IResult<&[u8], &[u8]> {
 
     let (remaining, data) = take(count)(remaining)?;
 
-    if !data.iter().all(|byte| is_char8(*byte)) {
-        // FIXME: what ErrorKind should this have?
-        return Err(nom::Err::Error(nom::error::Error::new(
-            remaining,
-            nom::error::ErrorKind::Verify,
-        )));
-    }
-
     Ok((remaining, data))
 }
 
-/// CHAR8 = %x01-ff ; any OCTET except NUL, %x00
-pub fn is_char8(i: u8) -> bool {
-    i != 0
-}
-
 // ----- astring ----- atom (roughly) or string
 
 // astring = 1*ASTRING-CHAR / string
@@ -285,6 +272,16 @@ mod tests {
         }
     }
 
+    #[test]
+    fn test_string_literal_containing_null() {
+        match string(b"{5}\r\nX\0Y\0Z") {
+            Ok((_, value)) => {
+                assert_eq!(value, b"X\0Y\0Z");
+            }
+            rsp => panic!("unexpected response {rsp:?}"),
+        }
+    }
+
     #[test]
     fn test_astring() {
         match astring(b"text ") {