Before going crazy

crates/project/src/file.rs

@@ -7,6 +7,15 @@ use serde::{Deserialize, Serialize};
 use crate::project::{Bank, Project};
 
 const VERSION: u8 = 1;
+pub const EXTENSION: &str = "cagire";
+
+pub fn ensure_extension(path: &Path) -> PathBuf {
+    if path.extension().map(|e| e == EXTENSION).unwrap_or(false) {
+        path.to_path_buf()
+    } else {
+        path.with_extension(EXTENSION)
+    }
+}
 
 #[derive(Serialize, Deserialize)]
 struct ProjectFile {
@@ -74,11 +83,12 @@ impl From<serde_json::Error> for FileError {
     }
 }
 
-pub fn save(project: &Project, path: &Path) -> Result<(), FileError> {
+pub fn save(project: &Project, path: &Path) -> Result<PathBuf, FileError> {
+    let path = ensure_extension(path);
     let file = ProjectFile::from(project);
     let json = serde_json::to_string_pretty(&file)?;
-    fs::write(path, json)?;
-    Ok(())
+    fs::write(&path, json)?;
+    Ok(path)
 }
 
 pub fn load(path: &Path) -> Result<Project, FileError> {