chore: Avoid collect in inner_main (#184)

src/main.rs

@@ -1,4 +1,4 @@
-use std::path::{Path, PathBuf};
+use std::path::PathBuf;
 use std::process::ExitCode;
 use std::sync::mpsc::channel;
 use std::time::Instant;
@@ -183,9 +183,7 @@ fn inner_main() -> Result<ExitCode> {
 
     set_up_logging(cli.verbose)?;
 
-    // TODO(charlie): Can we avoid this cast?
-    let paths: Vec<&Path> = cli.files.iter().map(PathBuf::as_path).collect();
-    let mut settings = Settings::from_paths(paths)?;
+    let mut settings = Settings::from_paths(&cli.files);
     if !cli.select.is_empty() {
         settings.select(cli.select);
     }

src/pyproject.rs

@@ -8,7 +8,7 @@ use serde::Deserialize;
 use crate::checks::CheckCode;
 use crate::fs;
 
-pub fn load_config<'a>(paths: impl IntoIterator<Item = &'a Path>) -> Result<(PathBuf, Config)> {
+pub fn load_config(paths: &[PathBuf]) -> (PathBuf, Config) {
     match find_project_root(paths) {
         Some(project_root) => match find_pyproject_toml(&project_root) {
             Some(path) => {
@@ -19,18 +19,18 @@ pub fn load_config<'a>(paths: impl IntoIterator<Item = &'a Path>) -> Result<(Pat
                             .tool
                             .and_then(|tool| tool.ruff)
                             .unwrap_or_default();
-                        Ok((project_root, config))
+                        (project_root, config)
                     }
                     Err(e) => {
                         println!("Failed to load pyproject.toml: {:?}", e);
                         println!("Falling back to default configuration...");
-                        Ok(Default::default())
+                        Default::default()
                     }
                 }
             }
-            None => Ok(Default::default()),
+            None => Default::default(),
         },
-        None => Ok(Default::default()),
+        None => Default::default(),
     }
 }
 
@@ -70,8 +70,8 @@ fn find_user_pyproject_toml() -> Option<PathBuf> {
     dirs::home_dir().map(|path| path.join(".ruff"))
 }
 
-fn find_project_root<'a>(sources: impl IntoIterator<Item = &'a Path>) -> Option<PathBuf> {
-    if let Some(prefix) = common_path_all(sources) {
+fn find_project_root(sources: &[PathBuf]) -> Option<PathBuf> {
+    if let Some(prefix) = common_path_all(sources.iter().map(PathBuf::as_path)) {
         for directory in prefix.ancestors() {
             if directory.join(".git").is_dir() {
                 return Some(directory.to_path_buf());
@@ -90,7 +90,7 @@ fn find_project_root<'a>(sources: impl IntoIterator<Item = &'a Path>) -> Option<
 
 #[cfg(test)]
 mod tests {
-    use std::path::Path;
+    use std::path::{Path, PathBuf};
 
     use anyhow::Result;
 
@@ -238,8 +238,9 @@ other-attribute = 1
 
     #[test]
     fn find_and_parse_pyproject_toml() -> Result<()> {
-        let project_root = find_project_root([Path::new("resources/test/fixtures/__init__.py")])
-            .expect("Unable to find project root.");
+        let project_root =
+            find_project_root(&[PathBuf::from("resources/test/fixtures/__init__.py")])
+                .expect("Unable to find project root.");
         assert_eq!(project_root, Path::new("resources/test/fixtures"));
 
         let path = find_pyproject_toml(&project_root).expect("Unable to find pyproject.toml.");

src/settings.rs

@@ -1,8 +1,7 @@
 use std::collections::BTreeSet;
 use std::hash::{Hash, Hasher};
-use std::path::Path;
+use std::path::PathBuf;
 
-use anyhow::Result;
 use glob::Pattern;
 
 use crate::checks::CheckCode;
@@ -25,8 +24,8 @@ impl Hash for Settings {
 }
 
 impl Settings {
-    pub fn from_paths<'a>(paths: impl IntoIterator<Item = &'a Path>) -> Result<Self> {
-        let (project_root, config) = load_config(paths)?;
+    pub fn from_paths(paths: &[PathBuf]) -> Self {
+        let (project_root, config) = load_config(paths);
         let mut settings = Settings {
             line_length: config.line_length.unwrap_or(88),
             exclude: config
@@ -89,7 +88,7 @@ impl Settings {
         if let Some(ignore) = &config.ignore {
             settings.ignore(ignore);
         }
-        Ok(settings)
+        settings
     }
 
     pub fn select(&mut self, codes: Vec<CheckCode>) {