Add settings hash to cache (#20)

src/bin/rust_python_linter.rs

@@ -95,7 +95,7 @@ fn main() -> Result<()> {
 
     set_up_logging(cli.verbose)?;
 
-    // TODO(charlie): Avoid this cast.
+    // TODO(charlie): Can we avoid this cast?
     let paths: Vec<&Path> = cli.files.iter().map(PathBuf::as_path).collect();
     let settings = Settings::from_paths(paths)?;
 

src/cache.rs

@@ -1,3 +1,5 @@
+use std::collections::hash_map::DefaultHasher;
+use std::hash::{Hash, Hasher};
 use std::os::unix::fs::MetadataExt;
 use std::path::Path;
 
@@ -6,6 +8,7 @@ use log::error;
 use serde::{Deserialize, Serialize};
 
 use crate::message::Message;
+use crate::settings::Settings;
 
 const VERSION: &str = env!("CARGO_PKG_VERSION");
 
@@ -67,20 +70,23 @@ fn cache_dir() -> &'static str {
     "./.cache"
 }
 
-fn cache_key(path: &Path) -> String {
+fn cache_key(path: &Path, settings: &Settings) -> String {
+    let mut hasher = DefaultHasher::new();
+    settings.hash(&mut hasher);
     format!(
-        "{}@{}",
+        "{}@{}@{}",
         path.canonicalize().unwrap().to_string_lossy(),
-        VERSION
+        VERSION,
+        hasher.finish()
     )
 }
 
-pub fn get(path: &Path, mode: &Mode) -> Option<Vec<Message>> {
+pub fn get(path: &Path, settings: &Settings, mode: &Mode) -> Option<Vec<Message>> {
     if !mode.allow_read() {
         return None;
     };
 
-    match cacache::read_sync(cache_dir(), cache_key(path)) {
+    match cacache::read_sync(cache_dir(), cache_key(path, settings)) {
         Ok(encoded) => match path.metadata() {
             Ok(m) => match bincode::deserialize::<CheckResult>(&encoded[..]) {
                 Ok(CheckResult { metadata, messages }) => {
@@ -98,7 +104,7 @@ pub fn get(path: &Path, mode: &Mode) -> Option<Vec<Message>> {
     None
 }
 
-pub fn set(path: &Path, messages: &[Message], mode: &Mode) {
+pub fn set(path: &Path, settings: &Settings, messages: &[Message], mode: &Mode) {
     if !mode.allow_write() {
         return;
     };
@@ -113,7 +119,7 @@ pub fn set(path: &Path, messages: &[Message], mode: &Mode) {
         };
         if let Err(e) = cacache::write_sync(
             cache_dir(),
-            cache_key(path),
+            cache_key(path, settings),
             bincode::serialize(&check_result).unwrap(),
         ) {
             error!("Failed to write to cache: {e:?}")

src/check_ast.rs

@@ -1,4 +1,4 @@
-use std::collections::HashSet;
+use std::collections::BTreeSet;
 
 use rustpython_parser::ast::{Arg, Arguments, Expr, ExprKind, Stmt, StmtKind, Suite};
 
@@ -99,7 +99,7 @@ impl Visitor for Checker<'_> {
             }
 
             // Search for duplicates.
-            let mut idents: HashSet<String> = HashSet::new();
+            let mut idents: BTreeSet<String> = BTreeSet::new();
             for arg in all_arguments {
                 let ident = &arg.node.arg;
                 if idents.contains(ident) {
@@ -130,8 +130,9 @@ pub fn check_ast(python_ast: &Suite, settings: &Settings) -> Vec<Check> {
 
 #[cfg(test)]
 mod tests {
+    use std::collections::BTreeSet;
+
     use rustpython_parser::ast::{Alias, Location, Stmt, StmtKind};
-    use std::collections::HashSet;
 
     use crate::check_ast::Checker;
     use crate::checks::CheckKind::ImportStarUsage;
@@ -144,7 +145,7 @@ mod tests {
         let settings = Settings {
             line_length: 88,
             exclude: vec![],
-            select: HashSet::from([CheckCode::F403]),
+            select: BTreeSet::from([CheckCode::F403]),
         };
         let mut checker = Checker::new(&settings);
         checker.visit_stmt(&Stmt {

src/checks.rs

@@ -1,7 +1,7 @@
 use rustpython_parser::ast::Location;
 use serde::{Deserialize, Serialize};
 
-#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Hash)]
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Hash, PartialOrd, Ord)]
 pub enum CheckCode {
     F831,
     F541,

src/linter.rs

@@ -13,7 +13,7 @@ use crate::{cache, fs};
 
 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) {
+    if let Some(messages) = cache::get(path, settings, mode) {
         debug!("Cache hit for: {}", path.to_string_lossy());
         return Ok(messages);
     }
@@ -53,14 +53,14 @@ pub fn check_path(path: &Path, settings: &Settings, mode: &cache::Mode) -> Resul
         })
         .filter(|message| !message.is_inline_ignored())
         .collect();
-    cache::set(path, &messages, mode);
+    cache::set(path, settings, &messages, mode);
 
     Ok(messages)
 }
 
 #[cfg(test)]
 mod tests {
-    use std::collections::HashSet;
+    use std::collections::BTreeSet;
     use std::path::Path;
 
     use anyhow::Result;
@@ -81,7 +81,7 @@ mod tests {
             &settings::Settings {
                 line_length: 88,
                 exclude: vec![],
-                select: HashSet::from([CheckCode::F831]),
+                select: BTreeSet::from([CheckCode::F831]),
             },
             &cache::Mode::None,
         )?;
@@ -117,7 +117,7 @@ mod tests {
             &settings::Settings {
                 line_length: 88,
                 exclude: vec![],
-                select: HashSet::from([CheckCode::F541]),
+                select: BTreeSet::from([CheckCode::F541]),
             },
             &cache::Mode::None,
         )?;
@@ -153,7 +153,7 @@ mod tests {
             &settings::Settings {
                 line_length: 88,
                 exclude: vec![],
-                select: HashSet::from([CheckCode::F634]),
+                select: BTreeSet::from([CheckCode::F634]),
             },
             &cache::Mode::None,
         )?;
@@ -184,7 +184,7 @@ mod tests {
             &settings::Settings {
                 line_length: 88,
                 exclude: vec![],
-                select: HashSet::from([CheckCode::F403]),
+                select: BTreeSet::from([CheckCode::F403]),
             },
             &cache::Mode::None,
         )?;
@@ -215,7 +215,7 @@ mod tests {
             &settings::Settings {
                 line_length: 88,
                 exclude: vec![],
-                select: HashSet::from([CheckCode::E501]),
+                select: BTreeSet::from([CheckCode::E501]),
             },
             &cache::Mode::None,
         )?;

src/pyproject.rs

@@ -1,12 +1,12 @@
-use std::collections::HashSet;
+use std::collections::BTreeSet;
 use std::path::{Path, PathBuf};
 
-use crate::checks::CheckCode;
 use anyhow::Result;
 use common_path::common_path_all;
 use log::debug;
 use serde::Deserialize;
 
+use crate::checks::CheckCode;
 use crate::fs;
 
 pub fn load_config<'a>(paths: impl IntoIterator<Item = &'a Path>) -> Result<(PathBuf, Config)> {
@@ -32,7 +32,7 @@ pub fn load_config<'a>(paths: impl IntoIterator<Item = &'a Path>) -> Result<(Pat
 pub struct Config {
     pub line_length: Option<usize>,
     pub exclude: Option<Vec<PathBuf>>,
-    pub select: Option<HashSet<CheckCode>>,
+    pub select: Option<BTreeSet<CheckCode>>,
 }
 
 #[derive(Debug, PartialEq, Eq, Deserialize)]
@@ -85,12 +85,12 @@ fn find_project_root<'a>(sources: impl IntoIterator<Item = &'a Path>) -> Option<
 
 #[cfg(test)]
 mod tests {
-    use std::collections::HashSet;
+    use std::collections::BTreeSet;
     use std::path::Path;
 
-    use crate::checks::CheckCode;
     use anyhow::Result;
 
+    use crate::checks::CheckCode;
     use crate::pyproject::{
         find_project_root, find_pyproject_toml, parse_pyproject_toml, Config, PyProject, Tools,
     };
@@ -173,7 +173,7 @@ select = ["E501"]
                 linter: Some(Config {
                     line_length: None,
                     exclude: None,
-                    select: Some(HashSet::from([CheckCode::E501])),
+                    select: Some(BTreeSet::from([CheckCode::E501])),
                 })
             })
         );

src/settings.rs

@@ -1,15 +1,25 @@
-use std::collections::HashSet;
+use std::collections::BTreeSet;
+use std::hash::{Hash, Hasher};
 use std::path::{Path, PathBuf};
 
-use crate::checks::CheckCode;
 use anyhow::Result;
 
+use crate::checks::CheckCode;
 use crate::pyproject::load_config;
 
 pub struct Settings {
     pub line_length: usize,
     pub exclude: Vec<PathBuf>,
-    pub select: HashSet<CheckCode>,
+    pub select: BTreeSet<CheckCode>,
+}
+
+impl Hash for Settings {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.line_length.hash(state);
+        for value in self.select.iter() {
+            value.hash(state);
+        }
+    }
 }
 
 impl Settings {
@@ -30,7 +40,7 @@ impl Settings {
                 })
                 .collect(),
             select: config.select.unwrap_or_else(|| {
-                HashSet::from([
+                BTreeSet::from([
                     CheckCode::F831,
                     CheckCode::F541,
                     CheckCode::F634,