Update to latest code head

Author: kevinkassimo

tokio/src/fs/try_exists.rs

@@ -1,14 +1,16 @@
 use crate::fs::asyncify;
+
+use std::io;
 use std::path::Path;
 
 /// Returns `Ok(true)` if the path points at an existing entity.
 ///
 /// This function will traverse symbolic links to query information about the
 /// destination file. In case of broken symbolic links this will return `Ok(false)`.
 ///
-/// This is the async equivalent of [`std::fs::try_exists`][std].
+/// This is the async equivalent of [`std::path::Path::try_exists`][std].
 ///
-/// [std]: fn@std::fs::try_exists
+/// [std]: fn@std::path::Path::try_exists
 ///
 /// # Examples
 ///
@@ -21,11 +23,7 @@ use std::path::Path;
 /// # }
 /// ```
 
-pub async fn try_exists(path: impl AsRef<Path>) -> Result<bool, std::io::Error> {
+pub async fn try_exists(path: impl AsRef<Path>) -> io::Result<bool> {
     let path = path.as_ref().to_owned();
-    match asyncify(move || std::fs::metadata(path)).await {
-        Ok(_) => Ok(true),
-        Err(error) if error.kind() == std::io::ErrorKind::NotFound => Ok(false),
-        Err(error) => Err(error),
-    }
+    asyncify(move || path.as_path().try_exists()).await
 }

tokio/tests/fs_try_exists.rs

@@ -0,0 +1,41 @@
+#![warn(rust_2018_idioms)]
+#![cfg(all(feature = "full", not(tokio_wasi)))] // Wasi does not support file operations
+
+use std::os::unix::prelude::PermissionsExt;
+
+use tempfile::tempdir;
+use tokio::fs;
+
+#[tokio::test]
+async fn try_exists() {
+    let dir = tempdir().unwrap();
+
+    let existing_path = dir.path().join("foo.txt");
+    fs::write(&existing_path, b"Hello File!").await.unwrap();
+    let nonexisting_path = dir.path().join("bar.txt");
+
+    assert_eq!(fs::try_exists(existing_path).await.unwrap(), true);
+    assert_eq!(fs::try_exists(nonexisting_path).await.unwrap(), false);
+
+    let permission_denied_directory_path = dir.path().join("baz");
+    fs::create_dir(&permission_denied_directory_path)
+        .await
+        .unwrap();
+    let permission_denied_file_path = permission_denied_directory_path.join("baz.txt");
+    fs::write(&permission_denied_file_path, b"Hello File!")
+        .await
+        .unwrap();
+    let mut perms = tokio::fs::metadata(&permission_denied_directory_path)
+        .await
+        .unwrap()
+        .permissions();
+    perms.set_mode(0o244);
+    fs::set_permissions(&permission_denied_directory_path, perms)
+        .await
+        .unwrap();
+    let permission_denied_result = fs::try_exists(permission_denied_file_path).await;
+    assert_eq!(
+        permission_denied_result.err().unwrap().kind(),
+        std::io::ErrorKind::PermissionDenied
+    );
+}