X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=library%2Fstd%2Fsrc%2Fio%2Ferror.rs;h=17e2b97545a94d43878659b6a972ebbb95452267;hb=3f4b039e33f2a6da6413bac416be97c1b0738ca8;hp=4b55324a2424cf45d424e44154b291db5ed3bd20;hpb=8429dcdb79b35182036e8de574287a7acc4b14d8;p=rust.git

diff --git a/library/std/src/io/error.rs b/library/std/src/io/error.rs
index 4b55324a242..17e2b97545a 100644
--- a/library/std/src/io/error.rs
+++ b/library/std/src/io/error.rs
@@ -141,6 +141,19 @@ struct Custom {
 /// It is used with the [`io::Error`] type.
 ///
 /// [`io::Error`]: Error
+///
+/// # Handling errors and matching on `ErrorKind`
+///
+/// In application code, use `match` for the `ErrorKind` values you are
+/// expecting; use `_` to match "all other errors".
+///
+/// In comprehensive and thorough tests that want to verify that a test doesn't
+/// return any known incorrect error kind, you may want to cut-and-paste the
+/// current full list of errors from here into your test code, and then match
+/// `_` as the correct case. This seems counterintuitive, but it will make your
+/// tests more robust. In particular, if you want to verify that your code does
+/// produce an unrecognized error kind, the robust solution is to check for all
+/// the recognized error kinds and fail in those cases.
 #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[allow(deprecated)]
@@ -296,12 +309,11 @@ pub enum ErrorKind {
     /// The filesystem does not support making so many hardlinks to the same file.
     #[unstable(feature = "io_error_more", issue = "86442")]
     TooManyLinks,
-    /// Filename too long.
+    /// A filename was invalid.
     ///
-    /// The limit might be from the underlying filesystem or API, or an administratively imposed
-    /// resource limit.
+    /// This error can also cause if it exceeded the filename length limit.
     #[unstable(feature = "io_error_more", issue = "86442")]
-    FilenameTooLong,
+    InvalidFilename,
     /// Program argument list too long.
     ///
     /// When trying to run an external program, a system or process limit on the size of the
@@ -382,12 +394,12 @@ pub(crate) fn as_str(&self) -> &'static str {
             DirectoryNotEmpty => "directory not empty",
             ExecutableFileBusy => "executable file busy",
             FileTooLarge => "file too large",
-            FilenameTooLong => "filename too long",
             FilesystemLoop => "filesystem loop or indirection limit (e.g. symlink loop)",
             FilesystemQuotaExceeded => "filesystem quota exceeded",
             HostUnreachable => "host unreachable",
             Interrupted => "operation interrupted",
             InvalidData => "invalid data",
+            InvalidFilename => "invalid filename",
             InvalidInput => "invalid input parameter",
             IsADirectory => "is a directory",
             NetworkDown => "network down",