From bbd71146b4b8f7a14f6ac131b981d76f3dae5a5e Mon Sep 17 00:00:00 2001
From: Ed Page <eopage@gmail.com>
Date: Sat, 8 Dec 2018 12:55:31 -0700
Subject: [PATCH] fix(error): Simplify by removing cloning

Most people don't support cloning, so eh.

BREAKING CHANGE: Error is now not cloneable
---
 liquid-error/src/clone.rs | 40 ---------------------------------------
 liquid-error/src/error.rs | 12 ++++++------
 liquid-error/src/lib.rs   |  2 --
 liquid-value/src/ser.rs   |  2 +-
 4 files changed, 7 insertions(+), 49 deletions(-)
 delete mode 100644 liquid-error/src/clone.rs

diff --git a/liquid-error/src/clone.rs b/liquid-error/src/clone.rs
deleted file mode 100644
index c786b698e..000000000
--- a/liquid-error/src/clone.rs
+++ /dev/null
@@ -1,40 +0,0 @@
-use std::error;
-use std::fmt;
-
-#[derive(Debug)]
-pub(crate) enum ClonableError {
-    Original(BoxedError),
-    Missing,
-}
-
-pub(crate) type BoxedError = Box<error::Error + Send + Sync + 'static>;
-
-impl ClonableError {
-    pub(crate) fn new(error: BoxedError) -> Self {
-        ClonableError::Original(error)
-    }
-
-    pub(crate) fn cause(&self) -> Option<&error::Error> {
-        match *self {
-            ClonableError::Original(ref e) => Some(e.as_ref()),
-            _ => None,
-        }
-    }
-}
-
-impl Clone for ClonableError {
-    fn clone(&self) -> Self {
-        match *self {
-            ClonableError::Original(_) | ClonableError::Missing => ClonableError::Missing,
-        }
-    }
-}
-
-impl fmt::Display for ClonableError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match *self {
-            ClonableError::Original(ref e) => fmt::Display::fmt(e, f),
-            ClonableError::Missing => write!(f, "Unknown error"),
-        }
-    }
-}
diff --git a/liquid-error/src/error.rs b/liquid-error/src/error.rs
index a1e59dc7c..d1cbeeab7 100644
--- a/liquid-error/src/error.rs
+++ b/liquid-error/src/error.rs
@@ -3,15 +3,15 @@ use std::error;
 use std::fmt;
 use std::result;
 
-use super::ClonableError;
-use super::BoxedError;
 use super::Trace;
 
 /// Convenience type alias for Liquid compiler errors
 pub type Result<T> = result::Result<T, Error>;
 
+type BoxedError = Box<error::Error + Send + Sync + 'static>;
+
 /// Compiler error
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 pub struct Error {
     inner: Box<InnerError>,
 }
@@ -20,11 +20,11 @@ pub struct Error {
 // `Result<T>` in the success case and spilling over from register-based returns to stack-based
 // returns.  There are already enough memory allocations below, one more
 // shouldn't hurt.
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 struct InnerError {
     msg: borrow::Cow<'static, str>,
     user_backtrace: Vec<Trace>,
-    cause: Option<ClonableError>,
+    cause: Option<BoxedError>,
 }
 
 impl Error {
@@ -89,7 +89,7 @@ impl Error {
     }
 
     fn cause_error(mut self, cause: BoxedError) -> Self {
-        let cause = Some(ClonableError::new(cause));
+        let cause = Some(cause);
         self.inner.cause = cause;
         self
     }
diff --git a/liquid-error/src/lib.rs b/liquid-error/src/lib.rs
index e2cdf0d23..4ccf1ae8c 100644
--- a/liquid-error/src/lib.rs
+++ b/liquid-error/src/lib.rs
@@ -4,12 +4,10 @@
 #![warn(missing_debug_implementations)]
 #![warn(unused_extern_crates)]
 
-mod clone;
 mod error;
 mod trace;
 mod result_ext;
 
 pub use error::*;
 pub use result_ext::*;
-use clone::*;
 use trace::*;
diff --git a/liquid-value/src/ser.rs b/liquid-value/src/ser.rs
index 9e77991a9..06ea07322 100644
--- a/liquid-value/src/ser.rs
+++ b/liquid-value/src/ser.rs
@@ -24,7 +24,7 @@ where
     value.serialize(Serializer).map_err(|e| e.0)
 }
 
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 struct SerError(error::Error);
 
 impl fmt::Display for SerError {