Avoid re-reading + iterating over lines for ignores (#48)

Cargo.lock

@@ -188,25 +188,6 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
-[[package]]
-name = "autoincrement"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dc81b6ad0c9122715c741113fb97ba283f723b1dd86e186dd7df00a2b6877bfe"
-dependencies = [
- "autoincrement_derive",
-]
-
-[[package]]
-name = "autoincrement_derive"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1259ce9b9a586a3f5ada3d236800ad0aa446b0d4c3dbac4158084a1dd704a228"
-dependencies = [
- "quote",
- "syn",
-]
-
 [[package]]
 name = "base64"
 version = "0.10.1"
@@ -1657,7 +1638,6 @@ name = "ruff"
 version = "0.0.19"
 dependencies = [
  "anyhow",
- "autoincrement",
  "bincode",
  "cacache",
  "chrono",

Cargo.toml

@@ -8,7 +8,6 @@ name = "ruff"
 
 [dependencies]
 anyhow = { version = "1.0.60" }
-autoincrement = "1.0.1"
 bincode = { version = "1.3.3" }
 cacache = { version = "10.0.1" }
 chrono = { version = "0.4.21" }

src/check_lines.rs

@@ -3,24 +3,36 @@ use rustpython_parser::ast::Location;
 use crate::checks::{Check, CheckKind};
 use crate::settings::Settings;
 
-pub fn check_lines(contents: &str, settings: &Settings) -> Vec<Check> {
-    contents
-        .lines()
-        .enumerate()
-        .filter_map(|(row, line)| {
-            if settings.select.contains(CheckKind::LineTooLong.code())
-                && line.len() > settings.line_length
-            {
-                let chunks: Vec<&str> = line.split_whitespace().collect();
-                if !(chunks.len() == 1 || (chunks.len() == 2 && chunks[0] == "#")) {
-                    return Some(Check {
-                        kind: CheckKind::LineTooLong,
-                        location: Location::new(row + 1, settings.line_length + 1),
-                    });
+pub fn check_lines(checks: &mut Vec<Check>, contents: &str, settings: &Settings) {
+    let enforce_line_too_ling = settings.select.contains(CheckKind::LineTooLong.code());
+
+    let mut line_checks = vec![];
+    let mut ignored = vec![];
+    for (row, line) in contents.lines().enumerate() {
+        // Remove any ignored checks.
+        // TODO(charlie): Only validate checks for the current line.
+        for (index, check) in checks.iter().enumerate() {
+            if check.location.row() == row + 1 && check.is_inline_ignored(line) {
+                ignored.push(index);
+            }
+        }
+
+        // Enforce line length.
+        if enforce_line_too_ling && line.len() > settings.line_length {
+            let chunks: Vec<&str> = line.split_whitespace().collect();
+            if !(chunks.len() == 1 || (chunks.len() == 2 && chunks[0] == "#")) {
+                let check = Check {
+                    kind: CheckKind::LineTooLong,
+                    location: Location::new(row + 1, settings.line_length + 1),
+                };
+                if !check.is_inline_ignored(line) {
+                    line_checks.push(check);
                 }
             }
-
-            None
-        })
-        .collect()
+        }
+    }
+    for index in ignored.iter().rev() {
+        checks.remove(*index);
+    }
+    checks.extend(line_checks);
 }

src/checks.rs

@@ -1,6 +1,7 @@
 use std::str::FromStr;
 
 use anyhow::Result;
+use regex::Regex;
 use rustpython_parser::ast::Location;
 use serde::{Deserialize, Serialize};
 
@@ -135,3 +136,28 @@ pub struct Check {
     pub kind: CheckKind,
     pub location: Location,
 }
+
+impl Check {
+    pub fn is_inline_ignored(&self, line: &str) -> bool {
+        let re = Regex::new(r"(?i)# noqa(?::\s?(?P<codes>([A-Z]+[0-9]+(?:[,\s]+)?)+))?").unwrap();
+        match re.captures(line) {
+            Some(caps) => match caps.name("codes") {
+                Some(codes) => {
+                    let re = Regex::new(r"[,\s]").unwrap();
+                    for code in re
+                        .split(codes.as_str())
+                        .map(|code| code.trim())
+                        .filter(|code| !code.is_empty())
+                    {
+                        if code == self.kind.code().as_str() {
+                            return true;
+                        }
+                    }
+                    false
+                }
+                None => true,
+            },
+            None => false,
+        }
+    }
+}

src/fs.rs

@@ -1,5 +1,5 @@
 use std::fs::File;
-use std::io::{BufRead, BufReader, Read};
+use std::io::{BufReader, Read};
 use std::path::{Path, PathBuf};
 
 use anyhow::Result;
@@ -22,16 +22,6 @@ pub fn iter_python_files(path: &PathBuf) -> impl Iterator<Item = DirEntry> {
         .filter(|entry| entry.path().to_string_lossy().ends_with(".py"))
 }
 
-pub fn read_line(path: &Path, row: &usize) -> Result<String> {
-    let file = File::open(path)?;
-    let buf_reader = BufReader::new(file);
-    buf_reader
-        .lines()
-        .nth(*row - 1)
-        .unwrap()
-        .map_err(|e| e.into())
-}
-
 pub fn read_file(path: &Path) -> Result<String> {
     let file = File::open(path)?;
     let mut buf_reader = BufReader::new(file);

src/linter.rs

@@ -36,13 +36,7 @@ pub fn check_path(path: &Path, settings: &Settings, mode: &cache::Mode) -> Resul
     }
 
     // Run the lines-based checks.
-    if settings
-        .select
-        .iter()
-        .any(|check_code| matches!(check_code.lint_source(), LintSource::Lines))
-    {
-        checks.extend(check_lines(&contents, settings));
-    }
+    check_lines(&mut checks, &contents, settings);
 
     // Convert to messages.
     let messages: Vec<Message> = checks
@@ -52,7 +46,6 @@ pub fn check_path(path: &Path, settings: &Settings, mode: &cache::Mode) -> Resul
             location: check.location,
             filename: path.to_string_lossy().to_string(),
         })
-        .filter(|message| !message.is_inline_ignored())
         .collect();
     cache::set(path, settings, &messages, mode);
 

src/message.rs

@@ -1,13 +1,10 @@
 use std::fmt;
-use std::path::Path;
 
 use colored::Colorize;
-use regex::Regex;
 use rustpython_parser::ast::Location;
 use serde::{Deserialize, Serialize};
 
 use crate::checks::CheckKind;
-use crate::fs;
 
 #[derive(Serialize, Deserialize)]
 #[serde(remote = "Location")]
@@ -32,38 +29,6 @@ pub struct Message {
     pub filename: String,
 }
 
-impl Message {
-    pub fn is_inline_ignored(&self) -> bool {
-        match fs::read_line(Path::new(&self.filename), &self.location.row()) {
-            Ok(line) => {
-                // https://github.com/PyCQA/flake8/blob/799c71eeb61cf26c7c176aed43e22523e2a6d991/src/flake8/defaults.py#L26
-                let re = Regex::new(r"(?i)# noqa(?::\s?(?P<codes>([A-Z]+[0-9]+(?:[,\s]+)?)+))?")
-                    .unwrap();
-                match re.captures(&line) {
-                    Some(caps) => match caps.name("codes") {
-                        Some(codes) => {
-                            let re = Regex::new(r"[,\s]").unwrap();
-                            for code in re
-                                .split(codes.as_str())
-                                .map(|code| code.trim())
-                                .filter(|code| !code.is_empty())
-                            {
-                                if code == self.kind.code().as_str() {
-                                    return true;
-                                }
-                            }
-                            false
-                        }
-                        None => true,
-                    },
-                    None => false,
-                }
-            }
-            Err(_) => false,
-        }
-    }
-}
-
 impl fmt::Display for Message {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         write!(