Implement E902 (IOError)

README.md

@@ -122,6 +122,7 @@ lint rules that are obviated by Black (e.g., stylistic rules).
 | ---- | ----- | ------- |
 | E402 | ModuleImportNotAtTopOfFile | Module level import not at top of file |
 | E501 | LineTooLong | Line too long |
+| E902 | IOError | No such file or directory: `...` |
 | F401 | UnusedImport | `...` imported but unused |
 | F403 | ImportStarUsage | Unable to detect undefined names |
 | F541 | FStringMissingPlaceholders | f-string without any placeholders |

examples/generate_rules_table.rs

@@ -8,6 +8,7 @@ fn main() {
         CheckKind::DuplicateArgumentName,
         CheckKind::FStringMissingPlaceholders,
         CheckKind::IfTuple,
+        CheckKind::IOError("...".to_string()),
         CheckKind::ImportStarUsage,
         CheckKind::LineTooLong,
         CheckKind::ModuleImportNotAtTopOfFile,

resources/test/fixtures/pyproject.toml

@@ -4,6 +4,7 @@ exclude = ["excluded.py", "**/migrations"]
 select = [
     "E402",
     "E501",
+    "E902",
     "F401",
     "F403",
     "F541",

src/checks.rs

@@ -10,6 +10,7 @@ use serde::{Deserialize, Serialize};
 pub enum CheckCode {
     E402,
     E501,
+    E902,
     F401,
     F403,
     F541,
@@ -35,6 +36,7 @@ impl FromStr for CheckCode {
         match s {
             "E402" => Ok(CheckCode::E402),
             "E501" => Ok(CheckCode::E501),
+            "E902" => Ok(CheckCode::E902),
             "F401" => Ok(CheckCode::F401),
             "F403" => Ok(CheckCode::F403),
             "F541" => Ok(CheckCode::F541),
@@ -61,6 +63,7 @@ impl CheckCode {
         match self {
             CheckCode::E402 => "E402",
             CheckCode::E501 => "E501",
+            CheckCode::E902 => "E902",
             CheckCode::F401 => "F401",
             CheckCode::F403 => "F403",
             CheckCode::F541 => "F541",
@@ -85,6 +88,7 @@ impl CheckCode {
         match self {
             CheckCode::E402 => &LintSource::AST,
             CheckCode::E501 => &LintSource::Lines,
+            CheckCode::E902 => &LintSource::FileSystem,
             CheckCode::F401 => &LintSource::AST,
             CheckCode::F403 => &LintSource::AST,
             CheckCode::F541 => &LintSource::AST,
@@ -109,6 +113,7 @@ impl CheckCode {
 pub enum LintSource {
     AST,
     Lines,
+    FileSystem,
 }
 
 #[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
@@ -117,6 +122,7 @@ pub enum CheckKind {
     DefaultExceptNotLast,
     DuplicateArgumentName,
     FStringMissingPlaceholders,
+    IOError(String),
     IfTuple,
     ImportStarUsage,
     LineTooLong,
@@ -141,6 +147,7 @@ impl CheckKind {
             CheckKind::DefaultExceptNotLast => "DefaultExceptNotLast",
             CheckKind::DuplicateArgumentName => "DuplicateArgumentName",
             CheckKind::FStringMissingPlaceholders => "FStringMissingPlaceholders",
+            CheckKind::IOError(_) => "IOError",
             CheckKind::IfTuple => "IfTuple",
             CheckKind::ImportStarUsage => "ImportStarUsage",
             CheckKind::LineTooLong => "LineTooLong",
@@ -165,6 +172,7 @@ impl CheckKind {
             CheckKind::DefaultExceptNotLast => &CheckCode::F707,
             CheckKind::DuplicateArgumentName => &CheckCode::F831,
             CheckKind::FStringMissingPlaceholders => &CheckCode::F541,
+            CheckKind::IOError(_) => &CheckCode::E902,
             CheckKind::IfTuple => &CheckCode::F634,
             CheckKind::ImportStarUsage => &CheckCode::F403,
             CheckKind::LineTooLong => &CheckCode::E501,
@@ -197,6 +205,9 @@ impl CheckKind {
             CheckKind::FStringMissingPlaceholders => {
                 "f-string without any placeholders".to_string()
             }
+            CheckKind::IOError(name) => {
+                format!("No such file or directory: `{name}`")
+            }
             CheckKind::IfTuple => "If test is a tuple, which is always `True`".to_string(),
             CheckKind::ImportStarUsage => "Unable to detect undefined names".to_string(),
             CheckKind::LineTooLong => "Line too long".to_string(),
@@ -242,6 +253,7 @@ impl CheckKind {
             CheckKind::DuplicateArgumentName => false,
             CheckKind::FStringMissingPlaceholders => false,
             CheckKind::IfTuple => false,
+            CheckKind::IOError(_) => false,
             CheckKind::ImportStarUsage => false,
             CheckKind::LineTooLong => false,
             CheckKind::ModuleImportNotAtTopOfFile => false,

src/main.rs

@@ -18,6 +18,7 @@ use ::ruff::logging::set_up_logging;
 use ::ruff::message::Message;
 use ::ruff::settings::Settings;
 use ::ruff::tell_user;
+use ruff::checks::CheckKind;
 
 const CARGO_PKG_NAME: &str = env!("CARGO_PKG_NAME");
 const CARGO_PKG_VERSION: &str = env!("CARGO_PKG_VERSION");
@@ -62,7 +63,7 @@ fn run_once(
 ) -> Result<Vec<Message>> {
     // Collect all the files to check.
     let start = Instant::now();
-    let files: Vec<DirEntry> = files
+    let paths: Vec<DirEntry> = files
         .iter()
         .flat_map(|path| iter_python_files(path, &settings.exclude))
         .collect();
@@ -70,7 +71,7 @@ fn run_once(
     debug!("Identified files to lint in: {:?}", duration);
 
     let start = Instant::now();
-    let mut messages: Vec<Message> = files
+    let mut messages: Vec<Message> = paths
         .par_iter()
         .map(|entry| {
             lint_path(entry.path(), settings, &cache.into(), &autofix.into()).unwrap_or_else(|e| {
@@ -80,6 +81,20 @@ fn run_once(
         })
         .flatten()
         .collect();
+
+    if settings.select.contains(&CheckCode::E902) {
+        for file in files {
+            if !file.exists() {
+                messages.push(Message {
+                    kind: CheckKind::IOError(file.to_string_lossy().to_string()),
+                    fixed: false,
+                    location: Default::default(),
+                    filename: file.to_string_lossy().to_string(),
+                })
+            }
+        }
+    }
+
     messages.sort_unstable();
     let duration = start.elapsed();
     debug!("Checked files in: {:?}", duration);

src/pyproject.rs

@@ -239,6 +239,7 @@ other-attribute = 1
                 select: Some(BTreeSet::from([
                     CheckCode::E402,
                     CheckCode::E501,
+                    CheckCode::E902,
                     CheckCode::F401,
                     CheckCode::F403,
                     CheckCode::F541,

src/settings.rs

@@ -46,6 +46,7 @@ impl Settings {
                 BTreeSet::from([
                     CheckCode::E402,
                     CheckCode::E501,
+                    CheckCode::E902,
                     CheckCode::F401,
                     CheckCode::F403,
                     CheckCode::F541,