Enable pycodestyle rules under new "nursery" category

crates/ruff/src/rule_selector.rs

@@ -119,8 +119,7 @@ impl Visitor<'_> for SelectorVisitor {
 
     fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
         formatter.write_str(
-            "expected a string code identifying a linter or specific rule, or a partial rule code \
-             or ALL to refer to all rules",
+            "expected a string code identifying a linter or specific rule, or a partial rule code or ALL to refer to all rules",
         )
     }
 
@@ -141,13 +140,22 @@ impl From<RuleCodePrefix> for RuleSelector {
     }
 }
 
+/// Returns `true` if the given rule should be selected by the `RuleSelector::All` selector.
+fn select_all(rule: Rule) -> bool {
+    // Nursery rules have to be explicitly selected, so we ignore them when looking at
+    // prefixes.
+    !rule.is_nursery()
+}
+
 impl IntoIterator for &RuleSelector {
-    type IntoIter = RuleSelectorIter;
     type Item = Rule;
+    type IntoIter = RuleSelectorIter;
 
     fn into_iter(self) -> Self::IntoIter {
         match self {
-            RuleSelector::All => RuleSelectorIter::All(Rule::iter()),
+            RuleSelector::All => {
+                RuleSelectorIter::All(Rule::iter().filter(|rule| select_all(*rule)))
+            }
             RuleSelector::C => RuleSelectorIter::Chain(
                 Linter::Flake8Comprehensions
                     .into_iter()
@@ -165,7 +173,7 @@ impl IntoIterator for &RuleSelector {
 }
 
 pub enum RuleSelectorIter {
-    All(RuleIter),
+    All(std::iter::Filter<RuleIter, fn(&Rule) -> bool>),
     Chain(std::iter::Chain<std::vec::IntoIter<Rule>, std::vec::IntoIter<Rule>>),
     Vec(std::vec::IntoIter<Rule>),
 }

crates/ruff_cli/src/commands/rule.rs

@@ -43,6 +43,17 @@ pub(crate) fn rule(rule: Rule, format: HelpFormat) -> Result<()> {
                 output.push('\n');
             }
 
+            if rule.is_nursery() {
+                output.push_str(&format!(
+                    r#"This rule is part of the **nursery**, a collection of newer lints that are
+still under development. As such, it must be enabled by explicitly selecting
+{}."#,
+                    rule.noqa_code()
+                ));
+                output.push('\n');
+                output.push('\n');
+            }
+
             if let Some(explanation) = rule.explanation() {
                 output.push_str(explanation.trim());
             } else {

crates/ruff_cli/tests/integration_test.rs

@@ -12,7 +12,7 @@ use path_absolutize::path_dedot;
 const BIN_NAME: &str = "ruff";
 
 #[test]
-fn test_stdin_success() -> Result<()> {
+fn stdin_success() -> Result<()> {
     let mut cmd = Command::cargo_bin(BIN_NAME)?;
     cmd.args(["-", "--format", "text", "--isolated"])
         .write_stdin("")
@@ -22,7 +22,7 @@ fn test_stdin_success() -> Result<()> {
 }
 
 #[test]
-fn test_stdin_error() -> Result<()> {
+fn stdin_error() -> Result<()> {
     let mut cmd = Command::cargo_bin(BIN_NAME)?;
     let output = cmd
         .args(["-", "--format", "text", "--isolated"])
@@ -40,7 +40,7 @@ Found 1 error.
 }
 
 #[test]
-fn test_stdin_filename() -> Result<()> {
+fn stdin_filename() -> Result<()> {
     let mut cmd = Command::cargo_bin(BIN_NAME)?;
     let output = cmd
         .args([
@@ -66,7 +66,7 @@ Found 1 error.
 
 #[cfg(unix)]
 #[test]
-fn test_stdin_json() -> Result<()> {
+fn stdin_json() -> Result<()> {
     let mut cmd = Command::cargo_bin(BIN_NAME)?;
     let output = cmd
         .args([
@@ -127,7 +127,7 @@ fn test_stdin_json() -> Result<()> {
 }
 
 #[test]
-fn test_stdin_autofix() -> Result<()> {
+fn stdin_autofix() -> Result<()> {
     let mut cmd = Command::cargo_bin(BIN_NAME)?;
     let output = cmd
         .args(["-", "--format", "text", "--fix", "--isolated"])
@@ -142,7 +142,7 @@ fn test_stdin_autofix() -> Result<()> {
 }
 
 #[test]
-fn test_stdin_autofix_when_not_fixable_should_still_print_contents() -> Result<()> {
+fn stdin_autofix_when_not_fixable_should_still_print_contents() -> Result<()> {
     let mut cmd = Command::cargo_bin(BIN_NAME)?;
     let output = cmd
         .args(["-", "--format", "text", "--fix", "--isolated"])
@@ -157,7 +157,7 @@ fn test_stdin_autofix_when_not_fixable_should_still_print_contents() -> Result<(
 }
 
 #[test]
-fn test_stdin_autofix_when_no_issues_should_still_print_contents() -> Result<()> {
+fn stdin_autofix_when_no_issues_should_still_print_contents() -> Result<()> {
     let mut cmd = Command::cargo_bin(BIN_NAME)?;
     let output = cmd
         .args(["-", "--format", "text", "--fix", "--isolated"])
@@ -172,7 +172,7 @@ fn test_stdin_autofix_when_no_issues_should_still_print_contents() -> Result<()>
 }
 
 #[test]
-fn test_show_source() -> Result<()> {
+fn show_source() -> Result<()> {
     let mut cmd = Command::cargo_bin(BIN_NAME)?;
     let output = cmd
         .args(["-", "--format", "text", "--show-source", "--isolated"])
@@ -217,3 +217,63 @@ fn show_statistics() -> Result<()> {
     );
     Ok(())
 }
+
+#[test]
+fn nursery_prefix() -> Result<()> {
+    let mut cmd = Command::cargo_bin(BIN_NAME)?;
+
+    // `--select E` should detect E741, but not E225, which is in the nursery.
+    let output = cmd
+        .args(["-", "--format", "text", "--isolated", "--select", "E"])
+        .write_stdin("I=42\n")
+        .assert()
+        .failure();
+    assert_eq!(
+        str::from_utf8(&output.get_output().stdout)?,
+        r#"-:1:1: E741 Ambiguous variable name: `I`
+Found 1 error.
+"#
+    );
+
+    Ok(())
+}
+
+#[test]
+fn nursery_all() -> Result<()> {
+    let mut cmd = Command::cargo_bin(BIN_NAME)?;
+
+    // `--select ALL` should detect E741, but not E225, which is in the nursery.
+    let output = cmd
+        .args(["-", "--format", "text", "--isolated", "--select", "E"])
+        .write_stdin("I=42\n")
+        .assert()
+        .failure();
+    assert_eq!(
+        str::from_utf8(&output.get_output().stdout)?,
+        r#"-:1:1: E741 Ambiguous variable name: `I`
+Found 1 error.
+"#
+    );
+
+    Ok(())
+}
+
+#[test]
+fn nursery_direct() -> Result<()> {
+    let mut cmd = Command::cargo_bin(BIN_NAME)?;
+
+    // `--select E225` should detect E225.
+    let output = cmd
+        .args(["-", "--format", "text", "--isolated", "--select", "E225"])
+        .write_stdin("I=42\n")
+        .assert()
+        .failure();
+    assert_eq!(
+        str::from_utf8(&output.get_output().stdout)?,
+        r#"-:1:2: E225 Missing whitespace around operator
+Found 1 error.
+"#
+    );
+
+    Ok(())
+}

crates/ruff_dev/src/generate_docs.rs

@@ -43,6 +43,17 @@ pub(crate) fn main(args: &Args) -> Result<()> {
                 output.push('\n');
             }
 
+            if rule.is_nursery() {
+                output.push_str(&format!(
+                    r#"This rule is part of the **nursery**, a collection of newer lints that are
+still under development. As such, it must be enabled by explicitly selecting
+{}."#,
+                    rule.noqa_code()
+                ));
+                output.push('\n');
+                output.push('\n');
+            }
+
             process_documentation(explanation.trim(), &mut output);
 
             let filename = PathBuf::from(ROOT_DIR)
@@ -116,7 +127,7 @@ mod tests {
 
     #[test]
     fn test_process_documentation() {
-        let mut out = String::new();
+        let mut output = String::new();
         process_documentation(
             "
 See also [`mccabe.max-complexity`].
@@ -127,10 +138,10 @@ Something [`else`][other].
 - `mccabe.max-complexity`
 
 [other]: http://example.com.",
-            &mut out,
+            &mut output,
         );
         assert_eq!(
-            out,
+            output,
             "
 See also [`mccabe.max-complexity`][mccabe.max-complexity].
 Something [`else`][other].

crates/ruff_diagnostics/src/violation.rs

@@ -1,6 +1,6 @@
 use std::fmt::{Debug, Display};
 
-#[derive(Copy, Clone)]
+#[derive(Debug, Copy, Clone)]
 pub enum AutofixKind {
     Sometimes,
     Always,
@@ -30,7 +30,7 @@ pub trait Violation: Debug + PartialEq + Eq {
         None
     }
 
-    // TODO micha: Move `autofix_title` to `Fix`, add new `advice` method that is shown as an advice.
+    // TODO(micha): Move `autofix_title` to `Fix`, add new `advice` method that is shown as an advice.
     // Change the `Diagnostic` renderer to show the advice, and render the fix message after the `Suggested fix: <here>`
 
     /// Returns the title for the autofix. The message is also shown as an advice as part of the diagnostics.

crates/ruff_macros/src/lib.rs

@@ -15,7 +15,7 @@ mod rule_namespace;
 mod violation;
 
 #[proc_macro_derive(ConfigurationOptions, attributes(option, doc, option_group))]
-pub fn derive_config(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+pub fn derive_config(input: TokenStream) -> TokenStream {
     let input = parse_macro_input!(input as DeriveInput);
 
     config::derive_impl(input)
@@ -43,13 +43,12 @@ pub fn cache_key(input: TokenStream) -> TokenStream {
 }
 
 #[proc_macro]
-pub fn register_rules(item: proc_macro::TokenStream) -> proc_macro::TokenStream {
+pub fn register_rules(item: TokenStream) -> TokenStream {
     let mapping = parse_macro_input!(item as register_rules::Input);
     register_rules::register_rules(&mapping).into()
 }
 
-/// Adds an `explanation()` method from the doc comment and
-/// `#[derive(Debug, PartialEq, Eq, serde::Serialize, serde::Deserialize)]`
+/// Adds an `explanation()` method from the doc comment.
 #[proc_macro_attribute]
 pub fn violation(_attr: TokenStream, item: TokenStream) -> TokenStream {
     let violation = parse_macro_input!(item as ItemStruct);
@@ -59,7 +58,7 @@ pub fn violation(_attr: TokenStream, item: TokenStream) -> TokenStream {
 }
 
 #[proc_macro_derive(RuleNamespace, attributes(prefix))]
-pub fn derive_rule_namespace(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+pub fn derive_rule_namespace(input: TokenStream) -> TokenStream {
     let input = parse_macro_input!(input as DeriveInput);
 
     rule_namespace::derive_impl(input)