From 9d1ef340465c57bd29dc7415b66918539e2ce5e1 Mon Sep 17 00:00:00 2001
From: Steven Sheldon <steven@sasheldon.com>
Date: Sun, 29 Dec 2019 15:18:54 -0800
Subject: [PATCH 1/3] Remove dependency on thiserror

---
 Cargo.toml   |  1 -
 src/error.rs | 53 +++++++++++++++++++++++++++++++++++++++++++---------
 2 files changed, 44 insertions(+), 10 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 06db597..3740fa1 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,7 +17,6 @@ quick-xml = { version = "0.17", features = ["encoding"] }
 derive_builder = "0.9"
 serde = { version = "1.0", optional = true, features = ["derive"] }
 chrono = "0.4"
-thiserror = "1.0"
 
 [features]
 with-serde = ["serde", "chrono/serde"]
diff --git a/src/error.rs b/src/error.rs
index 0ad3333..d79d026 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -1,24 +1,59 @@
+use std::error::Error as StdError;
+use std::fmt;
 use std::str::Utf8Error;
 
 use quick_xml::Error as XmlError;
-use thiserror::Error;
 
-#[derive(Debug, Error)]
+#[derive(Debug)]
 /// An error that occurred while performing an Atom operation.
 pub enum Error {
     /// Unable to parse XML.
-    #[error("{0}")]
-    Xml(#[from] XmlError),
+    Xml(XmlError),
     /// Unable to parse UTF8 in to a string.
-    #[error("{0}")]
-    Utf8(#[from] Utf8Error),
+    Utf8(Utf8Error),
     /// Input did not begin with an opening feed tag.
-    #[error("input did not begin with an opening feed tag")]
     InvalidStartTag,
     /// Unexpected end of input.
-    #[error("unexpected end of input")]
     Eof,
     /// The format of the timestamp is wrong.
-    #[error("timestamps must be formatted by RFC3339, rather than {0}")]
     WrongDatetime(String),
 }
+
+impl StdError for Error {
+    fn cause(&self) -> Option<&dyn StdError> {
+        match *self {
+            Error::Xml(ref err) => Some(err),
+            Error::Utf8(ref err) => Some(err),
+            Error::InvalidStartTag => None,
+            Error::Eof => None,
+            Error::WrongDatetime(_) => None,
+        }
+    }
+}
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match *self {
+            Error::Xml(ref err) => err.fmt(f),
+            Error::Utf8(ref err) => err.fmt(f),
+            Error::InvalidStartTag =>
+                write!(f, "input did not begin with an opening feed tag"),
+            Error::Eof =>
+                write!(f, "unexpected end of input"),
+            Error::WrongDatetime(ref datetime) =>
+                write!(f, "timestamps must be formatted by RFC3339, rather than {}", datetime),
+        }
+    }
+}
+
+impl From<XmlError> for Error {
+    fn from(err: XmlError) -> Error {
+        Error::Xml(err)
+    }
+}
+
+impl From<Utf8Error> for Error {
+    fn from(err: Utf8Error) -> Error {
+        Error::Utf8(err)
+    }
+}

From e7b6800965341332c6c35819066f76988926d448 Mon Sep 17 00:00:00 2001
From: Steven Sheldon <steven@sasheldon.com>
Date: Mon, 30 Dec 2019 20:27:06 -0800
Subject: [PATCH 2/3] Conform to rustfmt

---
 src/error.rs | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/error.rs b/src/error.rs
index d79d026..f19ab2f 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -36,12 +36,13 @@ impl fmt::Display for Error {
         match *self {
             Error::Xml(ref err) => err.fmt(f),
             Error::Utf8(ref err) => err.fmt(f),
-            Error::InvalidStartTag =>
-                write!(f, "input did not begin with an opening feed tag"),
-            Error::Eof =>
-                write!(f, "unexpected end of input"),
-            Error::WrongDatetime(ref datetime) =>
-                write!(f, "timestamps must be formatted by RFC3339, rather than {}", datetime),
+            Error::InvalidStartTag => write!(f, "input did not begin with an opening feed tag"),
+            Error::Eof => write!(f, "unexpected end of input"),
+            Error::WrongDatetime(ref datetime) => write!(
+                f,
+                "timestamps must be formatted by RFC3339, rather than {}",
+                datetime
+            ),
         }
     }
 }

From 081b5634b36790ff94fc711aa2c9e591189c52fb Mon Sep 17 00:00:00 2001
From: Steven Sheldon <steven@sasheldon.com>
Date: Fri, 3 Jan 2020 09:26:33 -0800
Subject: [PATCH 3/3] Use newer StdError API and ensure no ambiguity in fmt

---
 src/error.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/error.rs b/src/error.rs
index f19ab2f..8fdfeae 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -20,7 +20,7 @@ pub enum Error {
 }
 
 impl StdError for Error {
-    fn cause(&self) -> Option<&dyn StdError> {
+    fn source(&self) -> Option<&(dyn StdError + 'static)> {
         match *self {
             Error::Xml(ref err) => Some(err),
             Error::Utf8(ref err) => Some(err),
@@ -34,8 +34,8 @@ impl StdError for Error {
 impl fmt::Display for Error {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match *self {
-            Error::Xml(ref err) => err.fmt(f),
-            Error::Utf8(ref err) => err.fmt(f),
+            Error::Xml(ref err) => fmt::Display::fmt(err, f),
+            Error::Utf8(ref err) => fmt::Display::fmt(err, f),
             Error::InvalidStartTag => write!(f, "input did not begin with an opening feed tag"),
             Error::Eof => write!(f, "unexpected end of input"),
             Error::WrongDatetime(ref datetime) => write!(