Reduce the scope of clippy exceptions

This prevents creation of new overly complex functions.

src/configure/mod.rs

@@ -49,7 +49,7 @@ pub fn dc_is_configured(context: &Context) -> bool {
 /*******************************************************************************
  * Configure JOB
  ******************************************************************************/
-#[allow(non_snake_case, unused_must_use)]
+#[allow(non_snake_case, unused_must_use, clippy::cognitive_complexity)]
 pub fn JobConfigureImap(context: &Context) -> job::Status {
     if !context.sql.is_open() {
         error!(context, "Cannot configure, database not opened.",);

src/dc_receive_imf.rs

@@ -249,6 +249,7 @@ pub fn dc_receive_imf(
     Ok(())
 }
 
+#[allow(clippy::too_many_arguments, clippy::cognitive_complexity)]
 fn add_parts(
     context: &Context,
     mut mime_parser: &mut MimeMessage,
@@ -700,6 +701,7 @@ fn save_locations(
     }
 }
 
+#[allow(clippy::too_many_arguments)]
 fn calc_timestamps(
     context: &Context,
     chat_id: ChatId,
@@ -744,7 +746,7 @@ fn calc_timestamps(
 /// - create an ad-hoc group based on the recipient list
 ///
 /// on success the function returns the found/created (chat_id, chat_blocked) tuple .
-#[allow(non_snake_case)]
+#[allow(non_snake_case, clippy::cognitive_complexity)]
 fn create_or_lookup_group(
     context: &Context,
     mime_parser: &mut MimeMessage,

src/lib.rs

@@ -1,7 +1,5 @@
 #![forbid(unsafe_code)]
 #![deny(clippy::correctness, missing_debug_implementations, clippy::all)]
-// for now we hide warnings to not clutter/hide errors during "cargo clippy"
-#![allow(clippy::cognitive_complexity, clippy::too_many_arguments)]
 #![allow(clippy::match_bool)]
 #![feature(ptr_wrapping_offset_from)]
 #![feature(drain_filter)]

src/mimefactory.rs

@@ -576,6 +576,7 @@ impl<'a, 'b> MimeFactory<'a, 'b> {
         })
     }
 
+    #[allow(clippy::cognitive_complexity)]
     fn render_message(
         &mut self,
         protected_headers: &mut Vec<Header>,

src/mimeparser.rs

@@ -175,6 +175,7 @@ impl<'a> MimeMessage<'a> {
         Ok(parser)
     }
 
+    #[allow(clippy::cognitive_complexity)]
     fn parse_headers(&mut self) -> Result<()> {
         if self.get(HeaderDef::AutocryptSetupMessage).is_some() {
             self.parts.drain_filter(|part| {

src/sql.rs

@@ -365,6 +365,7 @@ fn table_exists(conn: &Connection, name: impl AsRef<str>) -> Result<bool> {
     Ok(exists)
 }
 
+#[allow(clippy::cognitive_complexity)]
 fn open(
     context: &Context,
     sql: &Sql,