Bump r2d2 dependency

Author: sfackler

Cargo.toml

@@ -18,5 +18,5 @@ name = "test"
 path = "tests/test.rs"
 
 [dependencies]
-r2d2 = "0.3"
+r2d2 = "0.4"
 postgres = "0.5"

src/lib.rs

@@ -61,7 +61,7 @@ impl error::Error for Error {
 ///     let config = Default::default();
 ///     let manager = PostgresConnectionManager::new("postgres://postgres@localhost",
 ///                                                  SslMode::None);
-///     let error_handler = r2d2::LoggingErrorHandler;
+///     let error_handler = Box::new(r2d2::LoggingErrorHandler);
 ///     let pool = Arc::new(r2d2::Pool::new(config, manager, error_handler).unwrap());
 ///
 ///     for i in 0..10i32 {

tests/test.rs

@@ -17,7 +17,7 @@ fn test_basic() {
         pool_size: 2,
         ..Default::default()
     };
-    let handler = r2d2::NoopErrorHandler;
+    let handler = Box::new(r2d2::NoopErrorHandler);
     let pool = Arc::new(r2d2::Pool::new(config, manager, handler).unwrap());
 
     let (s1, r1) = mpsc::channel();
@@ -53,7 +53,7 @@ fn test_is_valid() {
         test_on_check_out: true,
         ..Default::default()
     };
-    let handler = r2d2::NoopErrorHandler;
+    let handler = Box::new(r2d2::NoopErrorHandler);
     let pool = r2d2::Pool::new(config, manager, handler).unwrap();
 
     pool.get().unwrap();