Merge pull request #224 from erickt/path

feat(ser): Add ser::Error trait; avoid panic when serializing Paths

serde/src/ser/impls.rs

@@ -27,6 +27,7 @@ use std::sync::Arc;
 use core::nonzero::{NonZero, Zeroable};
 
 use super::{
+    Error,
     Serialize,
     Serializer,
     SeqVisitor,
@@ -682,7 +683,10 @@ impl Serialize for path::Path {
     fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
         where S: Serializer,
     {
-        self.to_str().unwrap().serialize(serializer)
+        match self.to_str() {
+            Some(s) => s.serialize(serializer),
+            None => Err(Error::invalid_value("Path contains invalid UTF-8 characters")),
+        }
     }
 }
 
@@ -690,7 +694,7 @@ impl Serialize for path::PathBuf {
     fn serialize<S>(&self, serializer: &mut S) -> Result<(), S::Error>
         where S: Serializer,
     {
-        self.to_str().unwrap().serialize(serializer)
+        self.as_path().serialize(serializer)
     }
 }
 

serde/src/ser/mod.rs

@@ -1,9 +1,25 @@
 //! Generic serialization framework.
 
+use std::error;
+
 pub mod impls;
 
 ///////////////////////////////////////////////////////////////////////////////
 
+/// `Error` is a trait that allows a `Serialize` to generically create a
+/// `Serializer` error.
+pub trait Error: Sized + error::Error {
+    /// Raised when there is general error when deserializing a type.
+    fn syntax(msg: &str) -> Self;
+
+    /// Raised when a `Serialize` was passed an incorrect value.
+    fn invalid_value(msg: &str) -> Self {
+        Error::syntax(msg)
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
 /// A trait that describes a type that can be serialized by a `Serializer`.
 pub trait Serialize {
     /// Serializes this value into this serializer.
@@ -16,7 +32,7 @@ pub trait Serialize {
 /// A trait that describes a type that can serialize a stream of values into the underlying format.
 pub trait Serializer {
     /// The error type that can be returned if some error occurs during serialization.
-    type Error;
+    type Error: Error;
 
     /// Serializes a `bool` value.
     fn serialize_bool(&mut self, v: bool) -> Result<(), Self::Error>;