Improve error message for ValidationError

In addition to the invalid character, the error now also contains a
`command_synopsis` and `argument` which identifies the command and
argument that failed to validate.

src/client.rs

@@ -41,8 +41,15 @@ impl<E> OptionExt<E> for Option<E> {
 /// grammar](https://tools.ietf.org/html/rfc3501#section-9)
 /// calls "quoted", which is reachable from "string" et al.
 /// Also ensure it doesn't contain a colliding command-delimiter (newline).
-pub(crate) fn validate_str(value: &str) -> Result<String> {
-    validate_str_noquote(value)?;
+///
+/// The arguments `synopsis` and `arg_name` are used to construct the error message of
+/// [ValidateError] in case validation fails.
+pub(crate) fn validate_str(
+    synopsis: impl Into<String>,
+    arg_name: impl Into<String>,
+    value: &str,
+) -> Result<String> {
+    validate_str_noquote(synopsis, arg_name, value)?;
     Ok(quote!(value))
 }
 
@@ -61,13 +68,26 @@ pub(crate) fn validate_str(value: &str) -> Result<String> {
 /// >             "BODY.PEEK" section ["<" number "." nz-number ">"]
 ///
 /// Note the lack of reference to any of the string-like rules or the quote characters themselves.
-fn validate_str_noquote(value: &str) -> Result<&str> {
+///
+/// The arguments `synopsis` and `arg_name` are used to construct the error message of
+/// [ValidateError] in case validation fails.
+fn validate_str_noquote(
+    synopsis: impl Into<String>,
+    arg_name: impl Into<String>,
+    value: &str,
+) -> Result<&str> {
     value
         .matches(|c| c == '\n' || c == '\r')
         .next()
         .and_then(|s| s.chars().next())
-        .map(|offender| Error::Validate(ValidateError(offender)))
-        .err()?;
+        .err()
+        .map_err(|c| {
+            Error::Validate(ValidateError {
+                command_synopsis: synopsis.into(),
+                argument: arg_name.into(),
+                offending_char: c,
+            })
+        })?;
     Ok(value)
 }
 
@@ -84,13 +104,23 @@ fn validate_str_noquote(value: &str) -> Result<&str> {
 ///
 /// Note the lack of reference to SP or any other such whitespace terminals.
 /// Per this grammar, in theory we ought to be even more restrictive than "no whitespace".
-fn validate_sequence_set(value: &str) -> Result<&str> {
+fn validate_sequence_set(
+    synopsis: impl Into<String>,
+    arg_name: impl Into<String>,
+    value: &str,
+) -> Result<&str> {
     value
         .matches(|c: char| c.is_ascii_whitespace())
         .next()
         .and_then(|s| s.chars().next())
-        .map(|offender| Error::Validate(ValidateError(offender)))
-        .err()?;
+        .err()
+        .map_err(|c| {
+            Error::Validate(ValidateError {
+                command_synopsis: synopsis.into(),
+                argument: arg_name.into(),
+                offending_char: c,
+            })
+        })?;
     Ok(value)
 }
 
@@ -347,8 +377,11 @@ impl<T: Read + Write> Client<T> {
         username: U,
         password: P,
     ) -> ::std::result::Result<Session<T>, (Error, Client<T>)> {
-        let u = ok_or_unauth_client_err!(validate_str(username.as_ref()), self);
-        let p = ok_or_unauth_client_err!(validate_str(password.as_ref()), self);
+        let synopsis = "LOGIN";
+        let u =
+            ok_or_unauth_client_err!(validate_str(synopsis, "username", username.as_ref()), self);
+        let p =
+            ok_or_unauth_client_err!(validate_str(synopsis, "password", password.as_ref()), self);
         ok_or_unauth_client_err!(
             self.run_command_and_check_ok(&format!("LOGIN {} {}", u, p)),
             self
@@ -494,7 +527,10 @@ impl<T: Read + Write> Session<T> {
     /// `EXISTS`, `FETCH`, and `EXPUNGE` responses. You can get them from the
     /// `unsolicited_responses` channel of the [`Session`](struct.Session.html).
     pub fn select<S: AsRef<str>>(&mut self, mailbox_name: S) -> Result<Mailbox> {
-        self.run(&format!("SELECT {}", validate_str(mailbox_name.as_ref())?))
+        self.run(&format!(
+            "SELECT {}",
+            validate_str("SELECT", "mailbox", mailbox_name.as_ref())?
+        ))
         .and_then(|(lines, _)| parse_mailbox(&lines[..], &mut self.unsolicited_responses_tx))
     }
 
@@ -503,7 +539,10 @@ impl<T: Read + Write> Session<T> {
     /// of the mailbox, including per-user state, will happen in a mailbox opened with `examine`;
     /// in particular, messagess cannot lose [`Flag::Recent`] in an examined mailbox.
     pub fn examine<S: AsRef<str>>(&mut self, mailbox_name: S) -> Result<Mailbox> {
-        self.run(&format!("EXAMINE {}", validate_str(mailbox_name.as_ref())?))
+        self.run(&format!(
+            "EXAMINE {}",
+            validate_str("EXAMINE", "mailbox", mailbox_name.as_ref())?
+        ))
         .and_then(|(lines, _)| parse_mailbox(&lines[..], &mut self.unsolicited_responses_tx))
     }
 
@@ -573,10 +612,11 @@ impl<T: Read + Write> Session<T> {
         if sequence_set.as_ref().is_empty() {
             Fetches::parse(vec![], &mut self.unsolicited_responses_tx)
         } else {
+            let synopsis = "FETCH";
             self.run_command_and_read_response(&format!(
                 "FETCH {} {}",
-                validate_sequence_set(sequence_set.as_ref())?,
-                validate_str_noquote(query.as_ref())?
+                validate_sequence_set(synopsis, "seq", sequence_set.as_ref())?,
+                validate_str_noquote(synopsis, "query", query.as_ref())?
             ))
             .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses_tx))
         }
@@ -592,10 +632,11 @@ impl<T: Read + Write> Session<T> {
         if uid_set.as_ref().is_empty() {
             Fetches::parse(vec![], &mut self.unsolicited_responses_tx)
         } else {
+            let synopsis = "UID FETCH";
             self.run_command_and_read_response(&format!(
                 "UID FETCH {} {}",
-                validate_sequence_set(uid_set.as_ref())?,
-                validate_str_noquote(query.as_ref())?
+                validate_sequence_set(synopsis, "seq", uid_set.as_ref())?,
+                validate_str_noquote(synopsis, "query", query.as_ref())?
             ))
             .and_then(|lines| Fetches::parse(lines, &mut self.unsolicited_responses_tx))
         }
@@ -646,7 +687,10 @@ impl<T: Read + Write> Session<T> {
     /// See the description of the [`UID`
     /// command](https://tools.ietf.org/html/rfc3501#section-6.4.8) for more detail.
     pub fn create<S: AsRef<str>>(&mut self, mailbox_name: S) -> Result<()> {
-        self.run_command_and_check_ok(&format!("CREATE {}", validate_str(mailbox_name.as_ref())?))
+        self.run_command_and_check_ok(&format!(
+            "CREATE {}",
+            validate_str("CREATE", "mailbox", mailbox_name.as_ref())?
+        ))
     }
 
     /// The [`DELETE` command](https://tools.ietf.org/html/rfc3501#section-6.3.4) permanently
@@ -669,7 +713,10 @@ impl<T: Read + Write> Session<T> {
     /// See the description of the [`UID`
     /// command](https://tools.ietf.org/html/rfc3501#section-6.4.8) for more detail.
     pub fn delete<S: AsRef<str>>(&mut self, mailbox_name: S) -> Result<()> {
-        self.run_command_and_check_ok(&format!("DELETE {}", validate_str(mailbox_name.as_ref())?))
+        self.run_command_and_check_ok(&format!(
+            "DELETE {}",
+            validate_str("DELETE", "mailbox", mailbox_name.as_ref())?
+        ))
     }
 
     /// The [`RENAME` command](https://tools.ietf.org/html/rfc3501#section-6.3.5) changes the name
@@ -944,7 +991,7 @@ impl<T: Read + Write> Session<T> {
         self.run_command_and_check_ok(&format!(
             "MOVE {} {}",
             sequence_set.as_ref(),
-            validate_str(mailbox_name.as_ref())?
+            validate_str("MOVE", "mailbox", mailbox_name.as_ref())?
         ))
     }
 
@@ -960,7 +1007,7 @@ impl<T: Read + Write> Session<T> {
         self.run_command_and_check_ok(&format!(
             "UID MOVE {} {}",
             uid_set.as_ref(),
-            validate_str(mailbox_name.as_ref())?
+            validate_str("UID MOVE", "mailbox", mailbox_name.as_ref())?
         ))
     }
 
@@ -1078,7 +1125,7 @@ impl<T: Read + Write> Session<T> {
         let mailbox_name = mailbox_name.as_ref();
         self.run_command_and_read_response(&format!(
             "STATUS {} {}",
-            validate_str(mailbox_name)?,
+            validate_str("STATUS", "mailbox", mailbox_name)?,
             data_items.as_ref()
         ))
         .and_then(|lines| {
@@ -1435,6 +1482,65 @@ impl<T: Read + Write> Connection<T> {
     }
 }
 
+#[cfg(test)]
+pub(crate) mod testutils {
+    use crate::mock_stream::MockStream;
+
+    use super::*;
+
+    pub(crate) fn assert_validation_error_client<F>(
+        run_command: F,
+        expected_synopsis: &'static str,
+        expected_argument: &'static str,
+        expected_char: char,
+    ) where
+        F: FnOnce(
+            Client<MockStream>,
+        ) -> std::result::Result<Session<MockStream>, (Error, Client<MockStream>)>,
+    {
+        let response = Vec::new();
+        let mock_stream = MockStream::new(response);
+        let client = Client::new(mock_stream);
+        assert_eq!(
+            run_command(client)
+                .expect_err("Error expected, but got success")
+                .0
+                .to_string(),
+            Error::Validate(ValidateError {
+                command_synopsis: expected_synopsis.to_owned(),
+                argument: expected_argument.to_string(),
+                offending_char: expected_char
+            })
+            .to_string()
+        );
+    }
+
+    pub(crate) fn assert_validation_error_session<F, R>(
+        run_command: F,
+        expected_synopsis: &'static str,
+        expected_argument: &'static str,
+        expected_char: char,
+    ) where
+        F: FnOnce(Session<MockStream>) -> Result<R>,
+    {
+        let response = Vec::new();
+        let mock_stream = MockStream::new(response);
+        let session = Session::new(Client::new(mock_stream).conn);
+        assert_eq!(
+            run_command(session)
+                .map(|_| ())
+                .expect_err("Error expected, but got success")
+                .to_string(),
+            Error::Validate(ValidateError {
+                command_synopsis: expected_synopsis.to_owned(),
+                argument: expected_argument.to_string(),
+                offending_char: expected_char
+            })
+            .to_string()
+        );
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::super::error::Result;
@@ -1443,6 +1549,8 @@ mod tests {
     use imap_proto::types::*;
     use std::borrow::Cow;
 
+    use super::testutils::*;
+
     macro_rules! mock_session {
         ($s:expr) => {
             Session::new(Client::new($s).conn)
@@ -1575,6 +1683,30 @@ mod tests {
         );
     }
 
+    #[test]
+    fn login_validation_username() {
+        let username = "username\n";
+        let password = "password";
+        assert_validation_error_client(
+            |client| client.login(username, password),
+            "LOGIN",
+            "username",
+            '\n',
+        );
+    }
+
+    #[test]
+    fn login_validation_password() {
+        let username = "username";
+        let password = "passw\rord";
+        assert_validation_error_client(
+            |client| client.login(username, password),
+            "LOGIN",
+            "password",
+            '\r',
+        );
+    }
+
     #[test]
     fn logout() {
         let response = b"a1 OK Logout completed.\r\n".to_vec();
@@ -1743,6 +1875,16 @@ mod tests {
         assert_eq!(mailbox, expected_mailbox);
     }
 
+    #[test]
+    fn examine_validation() {
+        assert_validation_error_session(
+            |mut session| session.examine("INB\nOX"),
+            "EXAMINE",
+            "mailbox",
+            '\n',
+        )
+    }
+
     #[test]
     fn select() {
         let response = b"* FLAGS (\\Answered \\Flagged \\Deleted \\Seen \\Draft)\r\n\
@@ -1791,6 +1933,16 @@ mod tests {
         assert_eq!(mailbox, expected_mailbox);
     }
 
+    #[test]
+    fn select_validation() {
+        assert_validation_error_session(
+            |mut session| session.select("INB\nOX"),
+            "SELECT",
+            "mailbox",
+            '\n',
+        )
+    }
+
     #[test]
     fn search() {
         let response = b"* SEARCH 1 2 3 4 5\r\n\
@@ -1906,6 +2058,16 @@ mod tests {
         );
     }
 
+    #[test]
+    fn create_validation() {
+        assert_validation_error_session(
+            |mut session| session.create("INB\nOX"),
+            "CREATE",
+            "mailbox",
+            '\n',
+        )
+    }
+
     #[test]
     fn delete() {
         let response = b"a1 OK DELETE completed\r\n".to_vec();
@@ -1920,6 +2082,16 @@ mod tests {
         );
     }
 
+    #[test]
+    fn delete_validation() {
+        assert_validation_error_session(
+            |mut session| session.delete("INB\nOX"),
+            "DELETE",
+            "mailbox",
+            '\n',
+        )
+    }
+
     #[test]
     fn noop() {
         let response = b"a1 OK NOOP completed\r\n".to_vec();
@@ -2008,6 +2180,16 @@ mod tests {
         );
     }
 
+    #[test]
+    fn mv_validation_query() {
+        assert_validation_error_session(
+            |mut session| session.mv("1:2", "MEE\nTING"),
+            "MOVE",
+            "mailbox",
+            '\n',
+        )
+    }
+
     #[test]
     fn uid_mv() {
         let response = b"* OK [COPYUID 1511554416 142,399 41:42] Moved UIDs.\r\n\
@@ -2026,11 +2208,41 @@ mod tests {
         );
     }
 
+    #[test]
+    fn uid_mv_validation_query() {
+        assert_validation_error_session(
+            |mut session| session.uid_mv("1:2", "MEE\nTING"),
+            "UID MOVE",
+            "mailbox",
+            '\n',
+        )
+    }
+
     #[test]
     fn fetch() {
         generic_fetch(" ", |c, seq, query| c.fetch(seq, query))
     }
 
+    #[test]
+    fn fetch_validation_seq() {
+        assert_validation_error_session(
+            |mut session| session.fetch("\r1", "BODY[]"),
+            "FETCH",
+            "seq",
+            '\r',
+        )
+    }
+
+    #[test]
+    fn fetch_validation_query() {
+        assert_validation_error_session(
+            |mut session| session.fetch("1", "BODY[\n]"),
+            "FETCH",
+            "query",
+            '\n',
+        )
+    }
+
     #[test]
     fn uid_fetch() {
         generic_fetch(" UID ", |c, seq, query| c.uid_fetch(seq, query))
@@ -2057,6 +2269,36 @@ mod tests {
         );
     }
 
+    #[test]
+    fn uid_fetch_validation_seq() {
+        assert_validation_error_session(
+            |mut session| session.uid_fetch("\r1", "BODY[]"),
+            "UID FETCH",
+            "seq",
+            '\r',
+        )
+    }
+
+    #[test]
+    fn uid_fetch_validation_query() {
+        assert_validation_error_session(
+            |mut session| session.uid_fetch("1", "BODY[\n]"),
+            "UID FETCH",
+            "query",
+            '\n',
+        )
+    }
+
+    #[test]
+    fn status_validation_mailbox() {
+        assert_validation_error_session(
+            |mut session| session.status("IN\nBOX", "(MESSAGES)"),
+            "STATUS",
+            "mailbox",
+            '\n',
+        )
+    }
+
     #[test]
     fn quote_backslash() {
         assert_eq!("\"test\\\\text\"", quote!(r"test\text"));
@@ -2071,15 +2313,15 @@ mod tests {
     fn validate_random() {
         assert_eq!(
             "\"~iCQ_k;>[&\\\"sVCvUW`e<<P!wJ\"",
-            &validate_str("~iCQ_k;>[&\"sVCvUW`e<<P!wJ").unwrap()
+            &validate_str("COMMAND", "arg1", "~iCQ_k;>[&\"sVCvUW`e<<P!wJ").unwrap()
         );
     }
 
     #[test]
     fn validate_newline() {
-        if let Err(ref e) = validate_str("test\nstring") {
+        if let Err(ref e) = validate_str("COMMAND", "arg1", "test\nstring") {
             if let &Error::Validate(ref ve) = e {
-                if ve.0 == '\n' {
+                if ve.offending_char == '\n' {
                     return;
                 }
             }
@@ -2091,9 +2333,9 @@ mod tests {
     #[test]
     #[allow(unreachable_patterns)]
     fn validate_carriage_return() {
-        if let Err(ref e) = validate_str("test\rstring") {
+        if let Err(ref e) = validate_str("COMMAND", "arg1", "test\rstring") {
             if let &Error::Validate(ref ve) = e {
-                if ve.0 == '\r' {
+                if ve.offending_char == '\r' {
                     return;
                 }
             }

src/error.rs

@@ -252,24 +252,53 @@ impl StdError for ParseError {
     }
 }
 
-/// An [invalid character](https://tools.ietf.org/html/rfc3501#section-4.3) was found in an input
-/// string.
+/// An [invalid character](https://tools.ietf.org/html/rfc3501#section-4.3) was found in a command
+/// argument.
 #[derive(Debug)]
-pub struct ValidateError(pub char);
+pub struct ValidateError {
+    /// the synopsis of the invalid command
+    pub(crate) command_synopsis: String,
+    /// the name of the invalid argument
+    pub(crate) argument: String,
+    /// the invalid character contained in the argument
+    pub(crate) offending_char: char,
+}
 
 impl fmt::Display for ValidateError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         // print character in debug form because invalid ones are often whitespaces
-        write!(f, "Invalid character in input: {:?}", self.0)
+        write!(
+            f,
+            "Invalid character {:?} in argument '{}' of command '{}'",
+            self.offending_char, self.argument, self.command_synopsis
+        )
     }
 }
 
 impl StdError for ValidateError {
     fn description(&self) -> &str {
-        "Invalid character in input"
+        "Invalid character in command argument"
     }
 
     fn cause(&self) -> Option<&dyn StdError> {
         None
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn validate_error_display() {
+        assert_eq!(
+            ValidateError {
+                command_synopsis: "COMMAND arg1 arg2".to_owned(),
+                argument: "arg2".to_string(),
+                offending_char: '\n'
+            }
+            .to_string(),
+            "Invalid character '\\n' in argument 'arg2' of command 'COMMAND arg1 arg2'"
+        );
+    }
+}

src/extensions/metadata.rs

@@ -23,19 +23,24 @@ use std::sync::mpsc;
 use crate::error::No;
 
 trait CmdListItemFormat {
-    fn format_as_cmd_list_item(&self) -> String;
+    fn format_as_cmd_list_item(&self, item_index: usize) -> Result<String>;
 }
 
 impl CmdListItemFormat for Metadata {
-    fn format_as_cmd_list_item(&self) -> String {
-        format!(
+    fn format_as_cmd_list_item(&self, item_index: usize) -> Result<String> {
+        let synopsis = "SETMETADATA";
+        Ok(format!(
             "{} {}",
-            validate_str(self.entry.as_str()).unwrap(),
+            validate_str(
+                synopsis,
+                &format!("entry#{}", item_index + 1),
+                self.entry.as_str()
+            )?,
             self.value
                 .as_ref()
-                .map(|v| validate_str(v.as_str()).unwrap())
-                .unwrap_or_else(|| "NIL".to_string())
-        )
+                .map(|v| validate_str(synopsis, &format!("value#{}", item_index + 1), v.as_str()))
+                .unwrap_or_else(|| Ok("NIL".to_string()))?
+        ))
     }
 }
 
@@ -168,10 +173,12 @@ impl<T: Read + Write> Session<T> {
         depth: MetadataDepth,
         maxsize: Option<usize>,
     ) -> Result<(Vec<Metadata>, Option<u64>)> {
+        let synopsis = "GETMETADATA";
         let v: Vec<String> = entries
             .iter()
-            .map(|e| validate_str(e.as_ref()).unwrap())
-            .collect();
+            .enumerate()
+            .map(|(i, e)| validate_str(synopsis, format!("entry#{}", i + 1), e.as_ref()))
+            .collect::<Result<_>>()?;
         let s = v.as_slice().join(" ");
         let mut command = format!("GETMETADATA (DEPTH {}", depth.depth_str());
 
@@ -183,8 +190,8 @@ impl<T: Read + Write> Session<T> {
             format!(
                 ") {} ({})",
                 mailbox
-                    .map(|mbox| validate_str(mbox).unwrap())
-                    .unwrap_or_else(|| "\"\"".to_string()),
+                    .map(|mbox| validate_str(synopsis, "mailbox", mbox))
+                    .unwrap_or_else(|| Ok("\"\"".to_string()))?,
                 s
             )
             .as_str(),
@@ -235,10 +242,15 @@ impl<T: Read + Write> Session<T> {
     pub fn set_metadata(&mut self, mbox: impl AsRef<str>, annotations: &[Metadata]) -> Result<()> {
         let v: Vec<String> = annotations
             .iter()
-            .map(|metadata| metadata.format_as_cmd_list_item())
-            .collect();
+            .enumerate()
+            .map(|(i, metadata)| metadata.format_as_cmd_list_item(i))
+            .collect::<Result<_>>()?;
         let s = v.as_slice().join(" ");
-        let command = format!("SETMETADATA {} ({})", validate_str(mbox.as_ref())?, s);
+        let command = format!(
+            "SETMETADATA {} ({})",
+            validate_str("SETMETADATA", "mailbox", mbox.as_ref())?,
+            s
+        );
         self.run_command_and_check_ok(command)
     }
 }
@@ -276,4 +288,175 @@ mod tests {
             Err(e) => panic!("Unexpected error: {:?}", e),
         }
     }
+
+    use crate::client::testutils::assert_validation_error_session;
+
+    #[test]
+    fn test_getmetadata_validation_entry1() {
+        assert_validation_error_session(
+            |mut session| {
+                session.get_metadata(
+                    None,
+                    &[
+                        "/shared/vendor\n/vendor.coi",
+                        "/shared/comment",
+                        "/some/other/entry",
+                    ],
+                    MetadataDepth::Infinity,
+                    None,
+                )
+            },
+            "GETMETADATA",
+            "entry#1",
+            '\n',
+        )
+    }
+
+    #[test]
+    fn test_getmetadata_validation_entry2() {
+        assert_validation_error_session(
+            |mut session| {
+                session.get_metadata(
+                    Some("INBOX"),
+                    &["/shared/vendor/vendor.coi", "/\rshared/comment"],
+                    MetadataDepth::Infinity,
+                    None,
+                )
+            },
+            "GETMETADATA",
+            "entry#2",
+            '\r',
+        )
+    }
+
+    #[test]
+    fn test_getmetadata_validation_mailbox() {
+        assert_validation_error_session(
+            |mut session| {
+                session.get_metadata(
+                    Some("INB\nOX"),
+                    &["/shared/vendor/vendor.coi", "/shared/comment"],
+                    MetadataDepth::Infinity,
+                    None,
+                )
+            },
+            "GETMETADATA",
+            "mailbox",
+            '\n',
+        );
+    }
+
+    #[test]
+    fn test_setmetadata_validation_mailbox() {
+        assert_validation_error_session(
+            |mut session| {
+                session.set_metadata(
+                    "INB\nOX",
+                    &[
+                        Metadata {
+                            entry: "/shared/vendor/vendor.coi".to_string(),
+                            value: None,
+                        },
+                        Metadata {
+                            entry: "/shared/comment".to_string(),
+                            value: Some("value".to_string()),
+                        },
+                    ],
+                )
+            },
+            "SETMETADATA",
+            "mailbox",
+            '\n',
+        );
+    }
+
+    #[test]
+    fn test_setmetadata_validation_entry1() {
+        assert_validation_error_session(
+            |mut session| {
+                session.set_metadata(
+                    "INBOX",
+                    &[
+                        Metadata {
+                            entry: "/shared/\nvendor/vendor.coi".to_string(),
+                            value: None,
+                        },
+                        Metadata {
+                            entry: "/shared/comment".to_string(),
+                            value: Some("value".to_string()),
+                        },
+                    ],
+                )
+            },
+            "SETMETADATA",
+            "entry#1",
+            '\n',
+        );
+    }
+
+    #[test]
+    fn test_setmetadata_validation_entry2_key() {
+        assert_validation_error_session(
+            |mut session| {
+                session.set_metadata(
+                    "INBOX",
+                    &[
+                        Metadata {
+                            entry: "/shared/vendor/vendor.coi".to_string(),
+                            value: None,
+                        },
+                        Metadata {
+                            entry: "/shared\r/comment".to_string(),
+                            value: Some("value".to_string()),
+                        },
+                    ],
+                )
+            },
+            "SETMETADATA",
+            "entry#2",
+            '\r',
+        );
+    }
+
+    #[test]
+    fn test_setmetadata_validation_entry2_value() {
+        assert_validation_error_session(
+            |mut session| {
+                session.set_metadata(
+                    "INBOX",
+                    &[
+                        Metadata {
+                            entry: "/shared/vendor/vendor.coi".to_string(),
+                            value: None,
+                        },
+                        Metadata {
+                            entry: "/shared/comment".to_string(),
+                            value: Some("va\nlue".to_string()),
+                        },
+                    ],
+                )
+            },
+            "SETMETADATA",
+            "value#2",
+            '\n',
+        );
+    }
+
+    #[test]
+    fn test_setmetadata_validation_entry() {
+        assert_validation_error_session(
+            |mut session| {
+                session.set_metadata(
+                    "INBOX",
+                    &[Metadata {
+                        entry: "/shared/\nvendor/vendor.coi".to_string(),
+                        value: None,
+                    }],
+                )
+            },
+            "SETMETADATA",
+            "entry#1",
+            '\n',
+        );
+    }
 }