Replace derive_more with declarative macros (#438)

Co-authored-by: Rob Ede <robjtede@icloud.com>

actix-tls/src/connect/connection.rs

@@ -1,17 +1,16 @@
-use derive_more::{Deref, DerefMut};
-
 use super::Host;
+use crate::impl_more;
 
 /// Wraps underlying I/O and the connection request that initiated it.
-#[derive(Debug, Deref, DerefMut)]
+#[derive(Debug)]
 pub struct Connection<R, IO> {
     pub(crate) req: R,
-
-    #[deref]
-    #[deref_mut]
     pub(crate) io: IO,
 }
 
+impl_more::deref! { Connection<R, IO> => io: IO }
+impl_more::deref_mut! { Connection<R, IO> => io }
+
 impl<R, IO> Connection<R, IO> {
     /// Construct new `Connection` from request and IO parts.
     pub(crate) fn new(req: R, io: IO) -> Self {

actix-tls/src/connect/error.rs

@@ -1,30 +1,38 @@
-use std::{error::Error, io};
-
-use derive_more::Display;
+use std::{error::Error, fmt, io};
 
 /// Errors that can result from using a connector service.
-#[derive(Debug, Display)]
+#[derive(Debug)]
 pub enum ConnectError {
-    /// Failed to resolve the hostname
-    #[display(fmt = "Failed resolving hostname")]
+    /// Failed to resolve the hostname.
     Resolver(Box<dyn std::error::Error>),
 
-    /// No DNS records
-    #[display(fmt = "No DNS records found for the input")]
+    /// No DNS records.
     NoRecords,
 
-    /// Invalid input
+    /// Invalid input.
     InvalidInput,
 
-    /// Unresolved host name
-    #[display(fmt = "Connector received `Connect` method with unresolved host")]
+    /// Unresolved host name.
     Unresolved,
 
-    /// Connection IO error
-    #[display(fmt = "{}", _0)]
+    /// Connection IO error.
     Io(io::Error),
 }
 
+impl fmt::Display for ConnectError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::NoRecords => f.write_str("No DNS records found for the input"),
+            Self::InvalidInput => f.write_str("Invalid input"),
+            Self::Unresolved => {
+                f.write_str("Connector received `Connect` method with unresolved host")
+            }
+            Self::Resolver(_) => f.write_str("Failed to resolve hostname"),
+            Self::Io(_) => f.write_str("I/O error"),
+        }
+    }
+}
+
 impl Error for ConnectError {
     fn source(&self) -> Option<&(dyn Error + 'static)> {
         match self {