Updated settings::utils::write_file’s signature for more flexibility

`write_file` now accepts as its second argument any type that
implements the `ToString` trait so that not only Strings will be
accepted but any type that can be turned into one.

src/settings/mod.rs

@@ -188,7 +188,7 @@ fn write_settings() {
 version: "1"
 categories: []
 rules: []"#;
-    utils::write_file(&path, serde_yaml::to_string(&s).unwrap()).unwrap();
+    utils::write_file(&path, &serde_yaml::to_string(&s).unwrap()).unwrap();
     assert_eq!(settings, utils::read_file(&path).unwrap());
 }
 

src/settings/utils.rs

@@ -44,7 +44,6 @@ pub fn read_file(path: &Path) -> Result<String> {
     }
 }
 
-pub fn write_file(path: &Path, content: String) -> Result<()> {
 /// Write a `String` into a file
 ///
 /// # Example
@@ -54,6 +53,10 @@ pub fn write_file(path: &Path, content: String) -> Result<()> {
 /// let path = std::path::Path::new("./path/to/my/file.txt");
 /// lang_evolve_core::settings::utils::write_file(&path, &content).unwrap();
 /// ```
+pub fn write_file<S>(path: &Path, content: &S) -> Result<()>
+where
+    S: std::string::ToString,
+{
     use std::io::prelude::*;
     let mut file = match File::create(&path) {
         Err(e) => {
@@ -62,7 +65,7 @@ pub fn write_file(path: &Path, content: String) -> Result<()> {
         }
         Ok(file) => file,
     };
-    match file.write_all(content.as_bytes()) {
+    match file.write_all(content.to_string().as_bytes()) {
         Err(e) => {
             warn!(
                 "Could not write settings to file {}: {}",