Rust 2018 idioms

src/lib.rs

@@ -62,17 +62,14 @@
 //! ```
 #![allow(unknown_lints)]
 
-extern crate libsqlite3_sys as ffi;
-extern crate lru_cache;
+use libsqlite3_sys as ffi;
+
 #[macro_use]
 extern crate bitflags;
 #[cfg(any(test, feature = "vtab"))]
 #[macro_use]
 extern crate lazy_static;
 
-#[cfg(feature = "i128_blob")]
-extern crate byteorder;
-
 use std::cell::RefCell;
 use std::convert;
 use std::default::Default;
@@ -142,7 +139,7 @@ pub mod vtab;
 // Number of cached prepared statements we'll hold on to.
 const STATEMENT_CACHE_DEFAULT_CAPACITY: usize = 16;
 /// To be used when your statement has no [parameter](https://sqlite.org/lang_expr.html#varparam).
-pub const NO_PARAMS: &[&ToSql] = &[];
+pub const NO_PARAMS: &[&dyn ToSql] = &[];
 
 /// A typedef of the result returned by many methods.
 pub type Result<T> = result::Result<T, Error>;
@@ -343,7 +340,7 @@ impl Connection {
     ///
     /// Will return `Err` if `sql` cannot be converted to a C-compatible string
     /// or if the underlying SQLite call fails.
-    pub fn execute_named(&self, sql: &str, params: &[(&str, &ToSql)]) -> Result<usize> {
+    pub fn execute_named(&self, sql: &str, params: &[(&str, &dyn ToSql)]) -> Result<usize> {
         self.prepare(sql)
             .and_then(|mut stmt| stmt.execute_named(params))
     }
@@ -383,7 +380,7 @@ impl Connection {
     where
         P: IntoIterator,
         P::Item: ToSql,
-        F: FnOnce(&Row) -> T,
+        F: FnOnce(&Row<'_, '_>) -> T,
     {
         let mut stmt = self.prepare(sql)?;
         stmt.query_row(params, f)
@@ -399,9 +396,9 @@ impl Connection {
     ///
     /// Will return `Err` if `sql` cannot be converted to a C-compatible string
     /// or if the underlying SQLite call fails.
-    pub fn query_row_named<T, F>(&self, sql: &str, params: &[(&str, &ToSql)], f: F) -> Result<T>
+    pub fn query_row_named<T, F>(&self, sql: &str, params: &[(&str, &dyn ToSql)], f: F) -> Result<T>
     where
-        F: FnOnce(&Row) -> T,
+        F: FnOnce(&Row<'_, '_>) -> T,
     {
         let mut stmt = self.prepare(sql)?;
         let mut rows = stmt.query_named(params)?;
@@ -438,7 +435,7 @@ impl Connection {
     where
         P: IntoIterator,
         P::Item: ToSql,
-        F: FnOnce(&Row) -> result::Result<T, E>,
+        F: FnOnce(&Row<'_, '_>) -> result::Result<T, E>,
         E: convert::From<Error>,
     {
         let mut stmt = self.prepare(sql)?;
@@ -594,7 +591,7 @@ impl Connection {
 }
 
 impl fmt::Debug for Connection {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_struct("Connection")
             .field("path", &self.path)
             .finish()
@@ -1055,12 +1052,12 @@ impl Drop for InnerConnection {
 
 #[cfg(test)]
 mod test {
-    extern crate tempdir;
     use self::tempdir::TempDir;
     pub use super::*;
     use crate::ffi;
     pub use std::error::Error as StdError;
     pub use std::fmt;
+    use tempdir;
 
     // this function is never called, but is still type checked; in
     // particular, calls with specific instantiations will require
@@ -1548,7 +1545,9 @@ mod test {
         for (i, v) in vals.iter().enumerate() {
             let i_to_insert = i as i64;
             assert_eq!(
-                insert_stmt.execute(&[&i_to_insert as &ToSql, &v]).unwrap(),
+                insert_stmt
+                    .execute(&[&i_to_insert as &dyn ToSql, &v])
+                    .unwrap(),
                 1
             );
         }
@@ -1566,7 +1565,7 @@ mod test {
     }
 
     mod query_and_then_tests {
-        extern crate libsqlite3_sys as ffi;
+
         use super::*;
 
         #[derive(Debug)]
@@ -1576,7 +1575,7 @@ mod test {
         }
 
         impl fmt::Display for CustomError {
-            fn fmt(&self, f: &mut fmt::Formatter) -> ::std::result::Result<(), fmt::Error> {
+            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> ::std::result::Result<(), fmt::Error> {
                 match *self {
                     CustomError::SomeError => write!(f, "{}", self.description()),
                     CustomError::Sqlite(ref se) => write!(f, "{}: {}", self.description(), se),
@@ -1589,7 +1588,7 @@ mod test {
                 "my custom error"
             }
 
-            fn cause(&self) -> Option<&StdError> {
+            fn cause(&self) -> Option<&dyn StdError> {
                 match *self {
                     CustomError::SomeError => None,
                     CustomError::Sqlite(ref se) => Some(se),