Improve API by making signatures more generic

src/database/json.rs

@@ -1,7 +1,7 @@
 //! Module for storing MusicHoard data in a JSON file database.
 
 use std::fs;
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
 
 use serde::de::DeserializeOwned;
 use serde::Serialize;
@@ -60,10 +60,8 @@ pub struct JsonDatabaseFileBackend {
 
 impl JsonDatabaseFileBackend {
     /// Create a [`JsonDatabaseFileBackend`] that will read/write to the provided path.
-    pub fn new(path: &Path) -> Self {
-        JsonDatabaseFileBackend {
-            path: path.to_path_buf(),
-        }
+    pub fn new<P: Into<PathBuf>>(path: P) -> Self {
+        JsonDatabaseFileBackend { path: path.into() }
     }
 }
 
@@ -144,7 +142,7 @@ mod tests {
         )
     }
 
-    fn artists_to_json(artists: &Vec<Artist>) -> String {
+    fn artists_to_json(artists: &[Artist]) -> String {
         let mut artists_strings: Vec<String> = vec![];
         for artist in artists.iter() {
             artists_strings.push(artist_to_json(artist));

src/library/beets.rs

@@ -3,7 +3,8 @@
 
 use std::{
     collections::{HashMap, HashSet},
-    path::{Path, PathBuf},
+    ffi::OsString,
+    path::PathBuf,
     process::Command,
     str,
 };
@@ -80,7 +81,7 @@ impl ToBeetsArgs for Query {
 #[cfg_attr(test, automock)]
 pub trait BeetsLibraryExecutor {
     /// Invoke beets with the provided arguments.
-    fn exec(&mut self, arguments: &[String]) -> Result<Vec<String>, Error>;
+    fn exec<S: AsRef<str> + 'static>(&mut self, arguments: &[S]) -> Result<Vec<String>, Error>;
 }
 
 /// Beets library.
@@ -90,7 +91,7 @@ pub struct BeetsLibrary<BLE> {
 
 trait LibraryPrivate {
     fn list_cmd_and_args(query: &Query) -> Vec<String>;
-    fn list_to_artists(list_output: Vec<String>) -> Result<Vec<Artist>, Error>;
+    fn list_to_artists<S: AsRef<str>>(list_output: &[S]) -> Result<Vec<Artist>, Error>;
 }
 
 impl<BLE: BeetsLibraryExecutor> BeetsLibrary<BLE> {
@@ -104,7 +105,7 @@ impl<BLE: BeetsLibraryExecutor> Library for BeetsLibrary<BLE> {
     fn list(&mut self, query: &Query) -> Result<Vec<Artist>, Error> {
         let cmd = Self::list_cmd_and_args(query);
         let output = self.executor.exec(&cmd)?;
-        Self::list_to_artists(output)
+        Self::list_to_artists(&output)
     }
 }
 
@@ -116,11 +117,11 @@ impl<BLE: BeetsLibraryExecutor> LibraryPrivate for BeetsLibrary<BLE> {
         cmd
     }
 
-    fn list_to_artists(list_output: Vec<String>) -> Result<Vec<Artist>, Error> {
+    fn list_to_artists<S: AsRef<str>>(list_output: &[S]) -> Result<Vec<Artist>, Error> {
         let mut artists: Vec<Artist> = vec![];
         let mut album_ids = HashMap::<ArtistId, HashSet<AlbumId>>::new();
 
-        for line in list_output.iter() {
+        for line in list_output.iter().map(|s| s.as_ref()) {
             if line.is_empty() {
                 continue;
             }
@@ -199,22 +200,22 @@ impl<BLE: BeetsLibraryExecutor> LibraryPrivate for BeetsLibrary<BLE> {
 
 /// Beets library executor that executes beets commands in their own process.
 pub struct BeetsLibraryCommandExecutor {
-    bin: String,
+    bin: OsString,
     config: Option<PathBuf>,
 }
 
 impl BeetsLibraryCommandExecutor {
     /// Create a new [`BeetsLibraryCommandExecutor`] that uses the provided beets executable.
-    pub fn new(bin: &str) -> Self {
+    pub fn new<S: Into<OsString>>(bin: S) -> Self {
         BeetsLibraryCommandExecutor {
-            bin: bin.to_string(),
+            bin: bin.into(),
             config: None,
         }
     }
 
     /// Update the configuration file passed to the beets executable.
-    pub fn config(mut self, path: Option<&Path>) -> Self {
-        self.config = path.map(|p| p.to_path_buf());
+    pub fn config<P: Into<PathBuf>>(mut self, path: Option<P>) -> Self {
+        self.config = path.map(|p| p.into());
         self
     }
 }
@@ -227,13 +228,13 @@ impl Default for BeetsLibraryCommandExecutor {
 }
 
 impl BeetsLibraryExecutor for BeetsLibraryCommandExecutor {
-    fn exec(&mut self, arguments: &[String]) -> Result<Vec<String>, Error> {
+    fn exec<S: AsRef<str> + 'static>(&mut self, arguments: &[S]) -> Result<Vec<String>, Error> {
         let mut cmd = Command::new(&self.bin);
         if let Some(ref path) = self.config {
             cmd.arg("--config");
             cmd.arg(path);
         }
-        let output = cmd.args(arguments).output()?;
+        let output = cmd.args(arguments.iter().map(|s| s.as_ref())).output()?;
         if !output.status.success() {
             return Err(Error::CmdExec(
                 String::from_utf8_lossy(&output.stderr).to_string(),
@@ -281,7 +282,7 @@ mod tests {
         strings
     }
 
-    fn artists_to_beets_string(artists: &Vec<Artist>) -> Vec<String> {
+    fn artists_to_beets_string(artists: &[Artist]) -> Vec<String> {
         let mut strings = vec![];
         for artist in artists.iter() {
             strings.append(&mut artist_to_beets_string(artist));

src/tui/app.rs

@@ -14,7 +14,7 @@ struct TrackSelection {
 }
 
 impl TrackSelection {
-    fn initialise(tracks: &Vec<Track>) -> Option<TrackSelection> {
+    fn initialise(tracks: &[Track]) -> Option<TrackSelection> {
         if !tracks.is_empty() {
             Some(TrackSelection { index: 0 })
         } else {
@@ -43,7 +43,7 @@ struct AlbumSelection {
 }
 
 impl AlbumSelection {
-    fn initialise(albums: &Vec<Album>) -> Option<AlbumSelection> {
+    fn initialise(albums: &[Album]) -> Option<AlbumSelection> {
         if !albums.is_empty() {
             Some(AlbumSelection {
                 index: 0,
@@ -77,7 +77,7 @@ struct ArtistSelection {
 }
 
 impl ArtistSelection {
-    fn initialise(artists: &Vec<Artist>) -> Option<ArtistSelection> {
+    fn initialise(artists: &[Artist]) -> Option<ArtistSelection> {
         if !artists.is_empty() {
             Some(ArtistSelection {
                 index: 0,