Add pyproject.toml support (#17)

.gitignore

@@ -1,7 +1,7 @@
 # Local cache
 .cache
-resources/test
 !resources/test/src
+resources/test
 
 ###
 # Rust.gitignore

Cargo.toml

@@ -15,6 +15,8 @@ chrono = { version = "0.4.21" }
 clap = { version = "3.2.16", features = ["derive"] }
 clearscreen = { version = "1.0.10" }
 colored = { version = "2.0.0" }
+common-path = "1.0.0"
+dirs = "4.0.0"
 fern = { version = "0.6.1" }
 lazy_static = { version = "1.4.0" }
 log = { version = "0.4.17" }
@@ -25,6 +27,7 @@ regex = { version = "1.6.0" }
 rustpython-parser = { git = "https://github.com/RustPython/RustPython.git", rev = "dff916d45c5d13074d21ad329a5ab68a6499426a" }
 serde = { version = "1.0.143", features = ["derive"] }
 serde_json = { version = "1.0.83" }
+toml = { version = "0.5.9"}
 walkdir = { version = "2.3.2" }
 
 [profile.release]

resources/test/src/pyproject.toml

@@ -0,0 +1,2 @@
+[tool.linter]
+line-length = 88

src/bin/rust_python_linter.rs

@@ -1,4 +1,4 @@
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use std::sync::mpsc::channel;
 use std::time::Instant;
 
@@ -15,6 +15,7 @@ use ::rust_python_linter::linter::check_path;
 use ::rust_python_linter::logging::set_up_logging;
 use ::rust_python_linter::message::Message;
 use ::rust_python_linter::tell_user;
+use rust_python_linter::settings::Settings;
 
 #[derive(Debug, Parser)]
 #[clap(name = "rust-python-linter")]
@@ -30,7 +31,7 @@ struct Cli {
     no_cache: bool,
 }
 
-fn run_once(files: &[PathBuf], cache: bool) -> Result<Vec<Message>> {
+fn run_once(files: &[PathBuf], settings: &Settings, cache: bool) -> Result<Vec<Message>> {
     // Collect all the files to check.
     let start = Instant::now();
     let files: Vec<DirEntry> = files.iter().flat_map(iter_python_files).collect();
@@ -41,7 +42,7 @@ fn run_once(files: &[PathBuf], cache: bool) -> Result<Vec<Message>> {
     let messages: Vec<Message> = files
         .par_iter()
         .map(|entry| {
-            check_path(entry.path(), &cache.into()).unwrap_or_else(|e| {
+            check_path(entry.path(), settings, &cache.into()).unwrap_or_else(|e| {
                 error!("Failed to check {}: {e:?}", entry.path().to_string_lossy());
                 vec![]
             })
@@ -88,12 +89,16 @@ fn main() -> Result<()> {
 
     set_up_logging(cli.verbose)?;
 
+    // TODO(charlie): Avoid this cast.
+    let paths: Vec<&Path> = cli.files.iter().map(PathBuf::as_path).collect();
+    let settings = Settings::from_paths(paths)?;
+
     if cli.watch {
         // Perform an initial run instantly.
         clearscreen::clear()?;
         tell_user!("Starting linter in watch mode...\n");
 
-        let messages = run_once(&cli.files, !cli.no_cache)?;
+        let messages = run_once(&cli.files, &settings, !cli.no_cache)?;
         report_continuously(&messages)?;
 
         // Configure the file watcher.
@@ -111,7 +116,7 @@ fn main() -> Result<()> {
                             clearscreen::clear()?;
                             tell_user!("File change detected...\n");
 
-                            let messages = run_once(&cli.files, !cli.no_cache)?;
+                            let messages = run_once(&cli.files, &settings, !cli.no_cache)?;
                             report_continuously(&messages)?;
                         }
                     }
@@ -120,7 +125,7 @@ fn main() -> Result<()> {
             }
         }
     } else {
-        let messages = run_once(&cli.files, !cli.no_cache)?;
+        let messages = run_once(&cli.files, &settings, !cli.no_cache)?;
         report_once(&messages)?;
     }
 

src/check_lines.rs

@@ -2,21 +2,21 @@ use rustpython_parser::ast::Location;
 
 use crate::checks::Check;
 use crate::checks::CheckKind::LineTooLong;
-use crate::settings::MAX_LINE_LENGTH;
+use crate::settings::Settings;
 
-pub fn check_lines(contents: &str) -> Vec<Check> {
+pub fn check_lines(contents: &str, settings: &Settings) -> Vec<Check> {
     contents
         .lines()
         .enumerate()
         .filter_map(|(row, line)| {
-            if line.len() > *MAX_LINE_LENGTH {
+            if line.len() > settings.line_length {
                 let chunks: Vec<&str> = line.split_whitespace().collect();
                 if chunks.len() == 1 || (chunks.len() == 2 && chunks[0] == "#") {
                     None
                 } else {
                     Some(Check {
                         kind: LineTooLong,
-                        location: Location::new(row + 1, MAX_LINE_LENGTH + 1),
+                        location: Location::new(row + 1, settings.line_length + 1),
                     })
                 }
             } else {

src/fs.rs

@@ -1,10 +1,11 @@
-use anyhow::Result;
-use lazy_static::lazy_static;
 use std::collections::HashSet;
 use std::fs::File;
 use std::io::{BufRead, BufReader, Read};
 use std::ops::Deref;
 use std::path::{Path, PathBuf};
+
+use anyhow::Result;
+use lazy_static::lazy_static;
 use walkdir::{DirEntry, WalkDir};
 
 lazy_static! {

src/lib.rs

@@ -6,5 +6,6 @@ pub mod fs;
 pub mod linter;
 pub mod logging;
 pub mod message;
-mod settings;
+mod pyproject;
+pub mod settings;
 mod visitor;

src/linter.rs

@@ -7,9 +7,10 @@ use rustpython_parser::parser;
 use crate::check_ast::check_ast;
 use crate::check_lines::check_lines;
 use crate::message::Message;
+use crate::settings::Settings;
 use crate::{cache, fs};
 
-pub fn check_path(path: &Path, mode: &cache::Mode) -> Result<Vec<Message>> {
+pub fn check_path(path: &Path, settings: &Settings, mode: &cache::Mode) -> Result<Vec<Message>> {
     // Check the cache.
     if let Some(messages) = cache::get(path, mode) {
         debug!("Cache hit for: {}", path.to_string_lossy());
@@ -23,7 +24,7 @@ pub fn check_path(path: &Path, mode: &cache::Mode) -> Result<Vec<Message>> {
     let python_ast = parser::parse_program(&contents)?;
     let messages: Vec<Message> = check_ast(&python_ast)
         .into_iter()
-        .chain(check_lines(&contents))
+        .chain(check_lines(&contents, settings))
         .map(|check| Message {
             kind: check.kind,
             location: check.location,
@@ -43,17 +44,18 @@ mod tests {
     use anyhow::Result;
     use rustpython_parser::ast::Location;
 
-    use crate::cache;
     use crate::checks::CheckKind::{
         DuplicateArgumentName, FStringMissingPlaceholders, IfTuple, ImportStarUsage, LineTooLong,
     };
     use crate::linter::check_path;
     use crate::message::Message;
+    use crate::{cache, settings};
 
     #[test]
     fn duplicate_argument_name() -> Result<()> {
         let actual = check_path(
             &Path::new("./resources/test/src/duplicate_argument_name.py"),
+            &settings::Settings { line_length: 88 },
             &cache::Mode::None,
         )?;
         let expected = vec![
@@ -85,6 +87,7 @@ mod tests {
     fn f_string_missing_placeholders() -> Result<()> {
         let actual = check_path(
             &Path::new("./resources/test/src/f_string_missing_placeholders.py"),
+            &settings::Settings { line_length: 88 },
             &cache::Mode::None,
         )?;
         let expected = vec![
@@ -116,6 +119,7 @@ mod tests {
     fn if_tuple() -> Result<()> {
         let actual = check_path(
             &Path::new("./resources/test/src/if_tuple.py"),
+            &settings::Settings { line_length: 88 },
             &cache::Mode::None,
         )?;
         let expected = vec![
@@ -142,6 +146,7 @@ mod tests {
     fn import_star_usage() -> Result<()> {
         let actual = check_path(
             &Path::new("./resources/test/src/import_star_usage.py"),
+            &settings::Settings { line_length: 88 },
             &cache::Mode::None,
         )?;
         let expected = vec![
@@ -168,6 +173,7 @@ mod tests {
     fn line_too_long() -> Result<()> {
         let actual = check_path(
             &Path::new("./resources/test/src/line_too_long.py"),
+            &settings::Settings { line_length: 88 },
             &cache::Mode::None,
         )?;
         let expected = vec![Message {