conf: add IMAP config in config parse test

src/conf.rs

@@ -1176,6 +1176,18 @@ format = "mbox"
 index_style = "Compact"
 identity="username@hostname.local"
 
+[composing]
+send_mail = '/bin/false'
+"#;
+    const IMAP_CONFIG: &str = r#"
+[accounts.imap]
+root_mailbox = "INBOX"
+format = "imap"
+identity="username@example.com"
+server_username = "null"
+server_hostname = "example.com"
+server_password_command = "/bin/false"
+
 [composing]
 send_mail = '/bin/false'
 "#;
@@ -1227,6 +1239,12 @@ send_mail = '/bin/false'
         "Unrecognised configuration values: {\"index_style\": \"Compact\"}"
     );
 
+    /* Test IMAP config */
+
+    let new_file = ConfigFile::new(IMAP_CONFIG).unwrap();
+    FileSettings::validate(new_file.path.clone(), false, true)
+        .expect("could not parse IMAP config");
+
     /* Test sample config */
 
     let example_config = EXAMPLE_CONFIG.replace("\n#", "\n");