style: use 'dyn' for trait objects

And also add a `source` method on the `Error` impl.

And finally, permit the use of the deprecated `description` method,
since removing it would be a breaking change.

3 files changed, 9 insertions, 5 deletions

diff --git a/src/error.rs b/src/error.rs
index ab9b17a..b084a58 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -203,6 +203,7 @@ impl Error {
 }
 
 impl error::Error for Error {
+    #[allow(deprecated)]
     fn description(&self) -> &str {
         match self.inner {
             ErrorInner::Io { ref err, .. } => err.description(),
@@ -210,7 +211,11 @@ impl error::Error for Error {
         }
     }
 
-    fn cause(&self) -> Option<&error::Error> {
+    fn cause(&self) -> Option<&dyn error::Error> {
+        self.source()
+    }
+
+    fn source(&self) -> Option<&(dyn error::Error + 'static)> {
         match self.inner {
             ErrorInner::Io { ref err, .. } => Some(err),
             ErrorInner::Loop { .. } => None,
diff --git a/src/lib.rs b/src/lib.rs
index 51778e4..6a7bd63 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -105,7 +105,6 @@ for entry in walker.filter_entry(|e| !is_hidden(e)) {
 
 #![deny(missing_docs)]
 #![allow(unknown_lints)]
-#![allow(bare_trait_objects)]
 
 #[cfg(test)]
 #[macro_use]
@@ -251,7 +250,7 @@ struct WalkDirOptions {
     min_depth: usize,
     max_depth: usize,
     sorter: Option<Box<
-        FnMut(&DirEntry,&DirEntry) -> Ordering + Send + Sync + 'static
+        dyn FnMut(&DirEntry,&DirEntry) -> Ordering + Send + Sync + 'static
     >>,
     contents_first: bool,
     same_file_system: bool,
diff --git a/src/tests/util.rs b/src/tests/util.rs
index d31a28d..ab977cd 100644
--- a/src/tests/util.rs
+++ b/src/tests/util.rs
@@ -11,12 +11,12 @@ use {DirEntry, Error};
 #[macro_export]
 macro_rules! err {
     ($($tt:tt)*) => {
-        Box::<error::Error + Send + Sync>::from(format!($($tt)*))
+        Box::<dyn error::Error + Send + Sync>::from(format!($($tt)*))
     }
 }
 
 /// A convenient result type alias.
-pub type Result<T> = result::Result<T, Box<error::Error + Send + Sync>>;
+pub type Result<T> = result::Result<T, Box<dyn error::Error + Send + Sync>>;
 
 /// The result of running a recursive directory iterator on a single directory.
 #[derive(Debug)]