even more improved errors

src/basic_types.rs

@@ -3,9 +3,10 @@ use serde::{Deserialize, Serialize};
 use std::{
     error::Error,
     fs::{self, read_to_string},
-    io::Write,
+    io::{self, Write},
     path::{Path, PathBuf},
 };
+use thiserror::Error;
 
 use crate::{
     conflict_resolver::ConflictSolver,
@@ -30,7 +31,7 @@ pub struct RootConfig {
 }
 
 impl RootConfig {
-    pub fn load_from_file(path: impl AsRef<Path>) -> Result<Self, Box<dyn Error>> {
+    pub fn load_from_file(path: impl AsRef<Path>) -> Result<Self, ConfigReadWriteError> {
         trace!(
             "Loading RootConfig from file: {}",
             path.as_ref().to_string_lossy()
@@ -51,10 +52,10 @@ impl RootConfig {
         self.mods.iter().find(|e| e.id == id).cloned()
     }
 
-    pub fn load_instance_by_id(&self, id: &str) -> Result<ModdedInstance, Box<dyn Error>> {
+    pub fn load_instance_by_id(&self, id: &str) -> Result<ModdedInstance, ConfigReadWriteError> {
         let conf = self
             .get_instance_config(id)
-            .ok_or("ID not found in root config")?;
+            .ok_or(ConfigReadWriteError::IDNotFound)?;
 
         ModdedInstance::load_from_file(&conf.path)
     }
@@ -116,7 +117,7 @@ impl ModdedInstance {
         }
     }
 
-    pub fn load_from_file(path: impl AsRef<Path>) -> Result<Self, Box<dyn Error>> {
+    pub fn load_from_file(path: impl AsRef<Path>) -> Result<Self, ConfigReadWriteError> {
         trace!(
             "Loading ModdedInstance from file: {}",
             path.as_ref().to_string_lossy()
@@ -128,7 +129,7 @@ impl ModdedInstance {
         Ok(config)
     }
 
-    pub fn save_to_file(&self, path: impl AsRef<Path>) -> Result<(), Box<dyn Error>> {
+    pub fn save_to_file(&self, path: impl AsRef<Path>) -> Result<(), ConfigReadWriteError> {
         trace!(
             "Saving ModdedInstance to: {}",
             path.as_ref().to_string_lossy()
@@ -290,3 +291,18 @@ impl ModFile {
         self.internal_priority
     }
 }
+
+#[derive(Error, Debug)]
+pub enum ConfigReadWriteError {
+    #[error("IO failure")]
+    Io(#[from] io::Error),
+
+    #[error("Failed to deserialize toml")]
+    Deserialize(#[from] toml::de::Error),
+
+    #[error("Failed to serialize to toml")]
+    Serialize(#[from] toml::ser::Error),
+
+    #[error("The provided ID could not be found")]
+    IDNotFound,
+}