feat(cli): error if path in config is not absolute

edu-sync/src/config.rs

@@ -1,10 +1,11 @@
+use serde::{Deserialize, Deserializer};
+use std::path::{Path, PathBuf};
 use std::{
     borrow::Cow,
     collections::BTreeMap,
     convert::Infallible,
     fmt::{self, Display},
     io::{self, ErrorKind},
-    path::{Path, PathBuf},
     sync::OnceLock,
 };
 
@@ -14,7 +15,7 @@ use edu_ws::{
     ws,
 };
 use reqwest::Url;
-use serde::{Deserialize, Serialize};
+use serde::Serialize;
 use serde_with::{serde_as, serde_conv, DisplayFromStr};
 use thiserror::Error;
 use tokio::{
@@ -105,6 +106,21 @@ impl CourseConfigs {
     }
 }
 
+// Custom deserializer function
+fn deserialize_absolute_path<'de, D>(deserializer: D) -> Result<PathBuf, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let path_str = String::deserialize(deserializer)?;
+    let path = PathBuf::from(path_str);
+
+    if !path.is_absolute() {
+        return Err(serde::de::Error::custom("Path must be absolute"));
+    }
+
+    Ok(path)
+}
+
 #[derive(Serialize, Deserialize, Debug)]
 #[serde(rename_all = "kebab-case")]
 pub struct AccountConfig {
@@ -113,6 +129,7 @@ pub struct AccountConfig {
     #[serde(flatten)]
     pub id: Id,
     pub token: Token,
+    #[serde(deserialize_with = "deserialize_absolute_path")]
     pub path: PathBuf,
     #[serde(default)]
     pub courses: CourseConfigs,