Add context to Error::DecodeError

Unfortunately esplugin doesn't expose similar context, so decode errors
it reports are handled as generic plugin parsing errors. A future
esplugin update will provide that context, at which point libloadorder
can be updated to use it.

src/enums.rs

@@ -17,7 +17,6 @@
  * along with libloadorder. If not, see <http://www.gnu.org/licenses/>.
  */
 
-use std::borrow::Cow;
 use std::convert::From;
 use std::error;
 use std::ffi::OsString;
@@ -81,7 +80,7 @@ pub enum Error {
     NoFilename(PathBuf),
     SystemTimeError(time::SystemTimeError),
     NotUtf8(Vec<u8>),
-    DecodeError(Cow<'static, str>),
+    DecodeError(Vec<u8>),
     EncodeError(String),
     PluginParsingError(PathBuf),
     PluginNotFound(String),
@@ -147,7 +146,7 @@ impl fmt::Display for Error {
                 write!(f, "The plugin path {path:?} has no filename part"),
             Error::SystemTimeError(error) => error.fmt(f),
             Error::NotUtf8(bytes) => write!(f, "Expected a UTF-8 string, got bytes {bytes:02X?}"),
-            Error::DecodeError(_) => write!(f, "Text could not be decoded from Windows-1252"),
+            Error::DecodeError(bytes) => write!(f, "String could not be decoded from Windows-1252, bytes are {bytes:02X?}"),
             Error::EncodeError(string) => write!(f, "The string \"{string}\" could not be encoded to Windows-1252"),
             Error::PluginParsingError(path) => {
                 write!(f, "An error was encountered while parsing the plugin at {path:?}")

src/load_order/mutable.rs

@@ -188,7 +188,7 @@ where
     // they get mapped to C1 control characters.
     let decoded_content = WINDOWS_1252
         .decode_without_bom_handling_and_without_replacement(&content)
-        .ok_or_else(|| Error::DecodeError("invalid sequence".into()))?;
+        .ok_or_else(|| Error::DecodeError(content.clone()))?;
 
     Ok(decoded_content.lines().filter_map(line_mapper).collect())
 }

src/plugin.rs

@@ -208,9 +208,7 @@ fn file_error(file_path: &Path, error: esplugin::Error) -> Error {
         esplugin::Error::ParsingIncomplete | esplugin::Error::ParsingError(_, _) => {
             Error::PluginParsingError(file_path.to_path_buf())
         }
-        esplugin::Error::DecodeError => {
-            Error::DecodeError("invalid byte sequence in plugin string".into())
-        }
+        esplugin::Error::DecodeError => Error::PluginParsingError(file_path.to_path_buf()),
     }
 }