fix build warning

src/checker.rs

@@ -1,12 +1,12 @@
-use std::fs;
+use finder::Checker;
+#[cfg(unix)]
+use libc;
 #[cfg(unix)]
 use std::ffi::CString;
+use std::fs;
 #[cfg(unix)]
 use std::os::unix::ffi::OsStrExt;
 use std::path::Path;
-#[cfg(unix)]
-use libc;
-use finder::Checker;
 
 pub struct ExecutableChecker;
 
@@ -47,7 +47,7 @@ impl Checker for ExistedChecker {
 }
 
 pub struct CompositeChecker {
-    checkers: Vec<Box<Checker>>,
+    checkers: Vec<Box<dyn Checker>>,
 }
 
 impl CompositeChecker {
@@ -57,7 +57,7 @@ impl CompositeChecker {
         }
     }
 
-    pub fn add_checker(mut self, checker: Box<Checker>) -> CompositeChecker {
+    pub fn add_checker(mut self, checker: Box<dyn Checker>) -> CompositeChecker {
         self.checkers.push(checker);
         self
     }

src/error.rs

@@ -8,7 +8,7 @@ pub struct Error {
     #[cfg(feature = "use_failure")]
     inner: Context<ErrorKind>,
     #[cfg(not(feature = "use_failure"))]
-    inner: ErrorKind
+    inner: ErrorKind,
 }
 
 // To suppress false positives from cargo-clippy
@@ -40,7 +40,7 @@ impl Display for ErrorKind {
 
 #[cfg(feature = "use_failure")]
 impl Fail for Error {
-    fn cause(&self) -> Option<&Fail> {
+    fn cause(&self) -> Option<&dyn Fail> {
         self.inner.cause()
     }
 
@@ -58,9 +58,13 @@ impl Display for Error {
 impl Error {
     pub fn kind(&self) -> ErrorKind {
         #[cfg(feature = "use_failure")]
-            { *self.inner.get_context() }
+        {
+            *self.inner.get_context()
+        }
         #[cfg(not(feature = "use_failure"))]
-            { self.inner }
+        {
+            self.inner
+        }
     }
 }
 

src/finder.rs

@@ -51,7 +51,7 @@ impl Finder {
         binary_name: T,
         paths: Option<U>,
         cwd: V,
-        binary_checker: &Checker,
+        binary_checker: &dyn Checker,
     ) -> Result<PathBuf>
     where
         T: AsRef<OsStr>,