Don't complain on missing default config

src/cli.rs

@@ -10,6 +10,7 @@ use crate::install::Mode;
 pub struct CliArgs {
     pub log_level: Level,
     pub config_path: PathBuf,
+    pub custom_config: bool,
     pub action: Action,
 }
 
@@ -76,8 +77,10 @@ pub fn parse_args() -> GenericResult<CliArgs> {
         _ => return Err!("Invalid verbosity level"),
     };
 
-    let config_path = matches.get_one("config").cloned().unwrap_or_else(||
-        PathBuf::from(shellexpand::tilde(DEFAULT_CONFIG_PATH).to_string()));
+    let (config_path, custom_config) = match matches.get_one("config").cloned() {
+        Some(path) => (path, true),
+        None => (PathBuf::from(shellexpand::tilde(DEFAULT_CONFIG_PATH).to_string()), false),
+    };
 
     let (command, matches) = matches.subcommand().unwrap();
 
@@ -103,5 +106,5 @@ pub fn parse_args() -> GenericResult<CliArgs> {
         _ => unreachable!(),
     };
 
-    Ok(CliArgs {log_level, config_path, action})
+    Ok(CliArgs {log_level, config_path, custom_config, action})
 }

src/config.rs

@@ -1,5 +1,6 @@
 use std::collections::BTreeMap;
 use std::fs::File;
+use std::io::{ErrorKind, Read};
 use std::path::{Path, PathBuf};
 
 use serde::Deserialize;
@@ -18,6 +19,7 @@ pub struct Config {
     #[serde(deserialize_with = "deserialize_path")]
     pub path: PathBuf,
 
+    #[serde(default)]
     #[validate(nested)]
     pub tools: BTreeMap<String, Tool>,
 
@@ -26,8 +28,18 @@ pub struct Config {
 }
 
 impl Config {
-    pub fn load(path: &Path) -> GenericResult<Config> {
-        let config: Config = serde_yaml::from_reader(File::open(path)?)?;
+    pub fn load(path: &Path, custom: bool) -> GenericResult<Config> {
+        let reader: Box<dyn Read> = match File::open(path) {
+            Ok(file) => Box::new(file),
+            Err(err) => {
+                if custom || err.kind() != ErrorKind::NotFound {
+                    return Err(err.into());
+                }
+                Box::new("{}".as_bytes())
+            },
+        };
+
+        let config: Config = serde_yaml::from_reader(reader)?;
         config.validate()?;
         Ok(config)
     }

src/main.rs

@@ -35,7 +35,7 @@ fn main() {
         process::exit(1);
     }
 
-    if let Err(err) = run(&args.config_path, args.action) {
+    if let Err(err) = run(&args.config_path, args.custom_config, args.action) {
         let message = err.to_string();
 
         if message.contains('\n') || message.ends_with('.') {
@@ -48,8 +48,8 @@ fn main() {
     }
 }
 
-fn run(config_path: &Path, action: Action) -> EmptyResult {
-    let config = Config::load(config_path).map_err(|e| format!(
+fn run(config_path: &Path, custom_config: bool, action: Action) -> EmptyResult {
+    let config = Config::load(config_path, custom_config).map_err(|e| format!(
         "Error while reading {:?} configuration file: {}", config_path, e))?;
 
     match action {

test

@@ -70,9 +70,12 @@ EOF
 )
 
 run() {
-    cargo run -- --config "$temp_dir/config.yaml" "$@"
+    cargo run --quiet -- --config "$temp_dir/config.yaml" "$@"
 }
 
+# Test work with missing default config
+cargo run --quiet -- list
+
 run list
 
 for command in install "install --force" upgrade; do