RUST-313 Mark enums as non-exhaustive where appropriate (#169)

Author: saghm

src/decoder/error.rs

@@ -4,6 +4,7 @@ use serde::de::{self, Expected, Unexpected};
 
 /// Possible errors that can arise during decoding.
 #[derive(Debug)]
+#[non_exhaustive]
 pub enum DecoderError {
     IoError(io::Error),
     FromUtf8Error(string::FromUtf8Error),

src/document.rs

@@ -24,6 +24,7 @@ use crate::{
 /// Error to indicate that either a value was empty or it contained an unexpected
 /// type, for use with the direct getters.
 #[derive(PartialEq)]
+#[non_exhaustive]
 pub enum ValueAccessError {
     /// Cannot find the expected field with the specified key
     NotPresent,

src/encoder/error.rs

@@ -6,6 +6,7 @@ use crate::bson::Bson;
 
 /// Possible errors that can arise during encoding.
 #[derive(Debug)]
+#[non_exhaustive]
 pub enum EncoderError {
     IoError(io::Error),
     InvalidMapKeyType(Bson),

src/oid.rs

@@ -27,6 +27,7 @@ static OID_COUNTER: AtomicUsize = AtomicUsize::new(0);
 
 /// Errors that can occur during OID construction and generation.
 #[derive(Debug)]
+#[non_exhaustive]
 pub enum Error {
     ArgumentError(String),
     FromHexError(FromHexError),

src/spec.rs

@@ -142,6 +142,7 @@ impl ElementType {
 
 /// The available binary subtypes, plus a user-defined slot.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
+#[non_exhaustive]
 pub enum BinarySubtype {
     Generic,
     Function,