refactor(config): Centralize loading logic

src/config.rs

@@ -1,3 +1,5 @@
+use std::io::Read;
+
 pub trait ConfigSource {
     /// Skip hidden files and directories.
     fn ignore_hidden(&self) -> Option<bool> {
@@ -43,6 +45,18 @@ pub struct Config {
 }
 
 impl Config {
+    pub fn from_file(path: &std::path::Path) -> Result<Self, failure::Error> {
+        let mut file = std::fs::File::open(path)?;
+        let mut s = String::new();
+        file.read_to_string(&mut s)?;
+        Self::from_toml(&s)
+    }
+
+    pub fn from_toml(data: &str) -> Result<Self, failure::Error> {
+        let content = toml::from_str(data)?;
+        Ok(content)
+    }
+
     pub fn update(&mut self, source: &dyn ConfigSource) {
         if let Some(source) = source.ignore_hidden() {
             self.ignore_hidden = Some(source);

src/main.rs

@@ -2,7 +2,6 @@
 #[macro_use]
 extern crate clap;
 
-use std::io::Read;
 use std::io::Write;
 
 use structopt::StructOpt;
@@ -45,7 +44,7 @@ struct Options {
 
     #[structopt(short = "c", long = "config")]
     /// Custom config file
-    custom_config: Option<String>,
+    custom_config: Option<std::path::PathBuf>,
 
     #[structopt(long, raw(overrides_with = r#""check-filenames""#))]
     /// Skip verifying spelling in file names.
@@ -258,10 +257,7 @@ fn run() -> Result<i32, failure::Error> {
 
     let mut config = config::Config::default();
     if let Some(path) = options.custom_config.as_ref() {
-        let mut file = std::fs::File::open(path)?;
+        let custom = config::Config::from_file(path)?;
-        let mut s = String::new();
-        file.read_to_string(&mut s)?;
-        let custom: config::Config = toml::from_str(&s)?;
         config.update(&custom);
     }
     config.update(&options);