From 04e6cbe44bb7a388bd61d1c9cfe4c618eb3b0e29 Mon Sep 17 00:00:00 2001
From: Markus Unterwaditzer <markus-honeypot@unterwaditzer.net>
Date: Sun, 23 Jan 2022 14:47:20 +0100
Subject: [PATCH] remove never type in favor of infallible

---
 src/lib.rs       |  2 --
 src/never.rs     | 24 ------------------------
 src/reader.rs    |  4 ++--
 src/tokenizer.rs | 10 ++++++----
 4 files changed, 8 insertions(+), 32 deletions(-)
 delete mode 100644 src/never.rs

diff --git a/src/lib.rs b/src/lib.rs
index 87d174a..4014522 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -14,7 +14,6 @@ mod entities;
 mod error;
 mod machine;
 mod machine_helper;
-mod never;
 mod read_helper;
 mod reader;
 mod tokenizer;
@@ -25,6 +24,5 @@ pub mod testutils;
 
 pub use emitter::{DefaultEmitter, Doctype, Emitter, EndTag, StartTag, Token};
 pub use error::Error;
-pub use never::Never;
 pub use reader::{IoReader, Readable, Reader, StringReader};
 pub use tokenizer::{InfallibleTokenizer, Tokenizer};
diff --git a/src/never.rs b/src/never.rs
deleted file mode 100644
index cb7d11c..0000000
--- a/src/never.rs
+++ /dev/null
@@ -1,24 +0,0 @@
-use std::error;
-use std::fmt;
-
-/// Definition of an empty enum.
-///
-/// This is used as the error type in situations where there can't be an error. A `Result<T, Never>`
-/// can be safely unwrapped and the `unwrap()` may be optimized away entirely.
-///
-/// This error is typically encountered when attempting to get tokens from the `Tokenizer`. Call
-/// [`crate::Tokenizer::infallible`] if you wish to avoid unwrapping those results yourself.
-pub enum Never {}
-
-impl fmt::Display for Never {
-    fn fmt(&self, _: &mut fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
-        match *self {}
-    }
-}
-impl fmt::Debug for Never {
-    fn fmt(&self, _: &mut fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
-        match *self {}
-    }
-}
-
-impl error::Error for Never {}
diff --git a/src/reader.rs b/src/reader.rs
index 3deaeea..99dc71b 100644
--- a/src/reader.rs
+++ b/src/reader.rs
@@ -1,5 +1,5 @@
-use crate::Never;
 use std::cmp::min;
+use std::convert::Infallible;
 use std::fs::File;
 use std::io::{self, Read};
 
@@ -152,7 +152,7 @@ impl<'a> StringReader<'a> {
 }
 
 impl<'a> Reader for StringReader<'a> {
-    type Error = Never;
+    type Error = Infallible;
 
     fn read_byte(&mut self) -> Result<Option<u8>, Self::Error> {
         if self.input.is_empty() {
diff --git a/src/tokenizer.rs b/src/tokenizer.rs
index df2424a..241b878 100644
--- a/src/tokenizer.rs
+++ b/src/tokenizer.rs
@@ -1,9 +1,11 @@
+use std::convert::Infallible;
+
 use crate::char_validator::CharValidator;
 use crate::machine;
 use crate::machine_helper::MachineHelper;
 use crate::read_helper::ReadHelper;
 use crate::utils::{ControlToken, State};
-use crate::{DefaultEmitter, Emitter, Never, Readable, Reader};
+use crate::{DefaultEmitter, Emitter, Readable, Reader};
 
 /// A HTML tokenizer. See crate-level docs for basic usage.
 pub struct Tokenizer<R: Reader, E: Emitter = DefaultEmitter> {
@@ -96,9 +98,9 @@ impl<R: Reader, E: Emitter> Iterator for Tokenizer<R, E> {
 /// `Result<Token, _>`.
 ///
 /// This is the return value of [`Tokenizer::infallible`].
-pub struct InfallibleTokenizer<R: Reader<Error = Never>, E: Emitter>(Tokenizer<R, E>);
+pub struct InfallibleTokenizer<R: Reader<Error = Infallible>, E: Emitter>(Tokenizer<R, E>);
 
-impl<R: Reader<Error = Never>, E: Emitter> Tokenizer<R, E> {
+impl<R: Reader<Error = Infallible>, E: Emitter> Tokenizer<R, E> {
     /// Statically assert that this iterator is infallible.
     ///
     /// Call this to get rid of error handling when parsing HTML from strings.
@@ -107,7 +109,7 @@ impl<R: Reader<Error = Never>, E: Emitter> Tokenizer<R, E> {
     }
 }
 
-impl<R: Reader<Error = Never>, E: Emitter> Iterator for InfallibleTokenizer<R, E> {
+impl<R: Reader<Error = Infallible>, E: Emitter> Iterator for InfallibleTokenizer<R, E> {
     type Item = E::Token;
 
     fn next(&mut self) -> Option<Self::Item> {