adjust parse_until_done to return an Option so it is more versatile

src/parse.rs

@@ -58,12 +58,14 @@ where
 /// Parse and return an expected single `T` Response with `F`.
 /// Responses other than `T` go into the `unsolicited` channel.
 ///
-/// If zero or more than one `T` is found then [`Error::Parse`] is returned
+/// If more than one `T` are found then [`Error::Parse`] is returned
+/// If zero `T` are found and optional is false then [`Error::Parse`] is returned, otherwise None is
 pub(crate) fn parse_until_done<'input, T, F>(
     input: &'input [u8],
+    optional: bool,
     unsolicited: &mut mpsc::Sender<UnsolicitedResponse>,
     map: F,
-) -> Result<T>
+) -> Result<Option<T>>
 where
     F: FnMut(Response<'input>) -> Result<MapOrNot<'input, T>>,
 {
@@ -72,7 +74,14 @@ where
     parse_many_into(input, &mut temp_output, unsolicited, map)?;
 
     match temp_output.len() {
-        1 => Ok(temp_output.remove(0)),
+        1 => Ok(Some(temp_output.remove(0))),
+        0 => {
+            if optional {
+                Ok(None)
+            } else {
+                Err(Error::Parse(ParseError::Invalid(input.to_vec())))
+            }
+        }
         _ => Err(Error::Parse(ParseError::Invalid(input.to_vec()))),
     }
 }

src/types/acls.rs

@@ -123,7 +123,7 @@ impl AclResponse {
             data: owned,
             acl_builder: |input| {
                 // There should only be ONE single ACL response
-                parse_until_done(input, unsolicited, |response| match response {
+                parse_until_done(input, false, unsolicited, |response| match response {
                     Response::Acl(a) => Ok(MapOrNot::Map(Acl {
                         mailbox: a.mailbox,
                         acls: a
@@ -137,6 +137,7 @@ impl AclResponse {
                     })),
                     resp => Ok(MapOrNot::Not(resp)),
                 })
+                .map(|o| o.unwrap())
             },
         }
         .try_build()
@@ -206,7 +207,7 @@ impl ListRightsResponse {
             data: owned,
             rights_builder: |input| {
                 // There should only be ONE single LISTRIGHTS response
-                parse_until_done(input, unsolicited, |response| match response {
+                parse_until_done(input, false, unsolicited, |response| match response {
                     Response::ListRights(a) => Ok(MapOrNot::Map(ListRights {
                         mailbox: a.mailbox,
                         identifier: a.identifier,
@@ -215,6 +216,7 @@ impl ListRightsResponse {
                     })),
                     resp => Ok(MapOrNot::Not(resp)),
                 })
+                .map(|o| o.unwrap())
             },
         }
         .try_build()
@@ -286,13 +288,14 @@ impl MyRightsResponse {
             data: owned,
             rights_builder: |input| {
                 // There should only be ONE single MYRIGHTS response
-                parse_until_done(input, unsolicited, |response| match response {
+                parse_until_done(input, false, unsolicited, |response| match response {
                     Response::MyRights(a) => Ok(MapOrNot::Map(MyRights {
                         mailbox: a.mailbox,
                         rights: a.rights.into(),
                     })),
                     resp => Ok(MapOrNot::Not(resp)),
                 })
+                .map(|o| o.unwrap())
             },
         }
         .try_build()