Use a char instead of a string in `.replace()`

acme_common/src/crypto.rs

@@ -58,7 +58,7 @@ impl FromStr for BaseHashFunction {
     type Err = Error;
 
     fn from_str(s: &str) -> Result<Self, Error> {
-        let s = s.to_lowercase().replace("-", "").replace("_", "");
+        let s = s.to_lowercase().replace('-', "").replace('_', "");
         match s.as_str() {
             "sha256" => Ok(BaseHashFunction::Sha256),
             "sha384" => Ok(BaseHashFunction::Sha384),

acme_common/src/crypto/key_type.rs

@@ -71,7 +71,7 @@ impl FromStr for KeyType {
     type Err = Error;
 
     fn from_str(s: &str) -> Result<Self, Error> {
-        match s.to_lowercase().replace("-", "_").as_str() {
+        match s.to_lowercase().replace('-', "_").as_str() {
             "rsa2048" => Ok(KeyType::Rsa2048),
             "rsa4096" => Ok(KeyType::Rsa4096),
             "ecdsa_p256" => Ok(KeyType::EcdsaP256),

acme_common/src/crypto/openssl_keys.rs

@@ -269,8 +269,8 @@ impl KeyPair {
                 x += &pem_line
                     .trim()
                     .trim_end_matches('=')
-                    .replace("/", "_")
-                    .replace("+", "-");
+                    .replace('/', "_")
+                    .replace('+', "-");
             }
         }
         x.replace_range(..16, "");

acmed/src/config.rs

@@ -483,7 +483,7 @@ impl Certificate {
                 id.to_string()
             }
         };
-        let name = name.replace("*", "_").replace(":", "_").replace("/", "_");
+        let name = name.replace('*', "_").replace(':', "_").replace('/', "_");
         Ok(name)
     }