[pygrep_hooks] Add fix for deprecated-log-warn (PGH002) (#9519)

## Summary

add autofix for `deprecated_log_warn` (`PGH002`)

## Test Plan

`cargo test`

---------

Co-authored-by: Charlie Marsh <charlie.r.marsh@gmail.com>

crates/ruff_linter/src/rules/pygrep_hooks/mod.rs

@@ -9,6 +9,8 @@ mod tests {
     use test_case::test_case;
 
     use crate::registry::Rule;
+    use crate::settings::types::PreviewMode;
+    use crate::settings::LinterSettings;
     use crate::test::test_path;
     use crate::{assert_messages, settings};
 
@@ -29,4 +31,22 @@ mod tests {
         assert_messages!(snapshot, diagnostics);
         Ok(())
     }
+
+    #[test_case(Rule::DeprecatedLogWarn, Path::new("PGH002_1.py"))]
+    fn preview_rules(rule_code: Rule, path: &Path) -> Result<()> {
+        let snapshot = format!(
+            "preview__{}_{}",
+            rule_code.noqa_code(),
+            path.to_string_lossy()
+        );
+        let diagnostics = test_path(
+            Path::new("pygrep_hooks").join(path).as_path(),
+            &LinterSettings {
+                preview: PreviewMode::Enabled,
+                ..LinterSettings::for_rule(rule_code)
+            },
+        )?;
+        assert_messages!(snapshot, diagnostics);
+        Ok(())
+    }
 }

crates/ruff_linter/src/rules/pygrep_hooks/rules/deprecated_log_warn.rs

@@ -1,12 +1,12 @@
-use ruff_python_ast::{self as ast, Expr, ExprCall};
+use ruff_diagnostics::{Diagnostic, Edit, Fix, FixAvailability, Violation};
-use ruff_python_semantic::analyze::logging;
-
-use ruff_diagnostics::{Diagnostic, Violation};
 use ruff_macros::{derive_message_formats, violation};
+use ruff_python_ast::{self as ast, Expr};
+use ruff_python_semantic::analyze::logging;
 use ruff_python_stdlib::logging::LoggingLevel;
 use ruff_text_size::Ranged;
 
 use crate::checkers::ast::Checker;
+use crate::importer::ImportRequest;
 
 /// ## What it does
 /// Check for usages of the deprecated `warn` method from the `logging` module.
@@ -38,14 +38,20 @@ use crate::checkers::ast::Checker;
 pub struct DeprecatedLogWarn;
 
 impl Violation for DeprecatedLogWarn {
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::Sometimes;
+
     #[derive_message_formats]
     fn message(&self) -> String {
         format!("`warn` is deprecated in favor of `warning`")
     }
+
+    fn fix_title(&self) -> Option<String> {
+        Some(format!("Replace with `warning`"))
+    }
 }
 
 /// PGH002
-pub(crate) fn deprecated_log_warn(checker: &mut Checker, call: &ExprCall) {
+pub(crate) fn deprecated_log_warn(checker: &mut Checker, call: &ast::ExprCall) {
     match call.func.as_ref() {
         Expr::Attribute(ast::ExprAttribute { attr, .. }) => {
             if !logging::is_logger_candidate(
@@ -74,7 +80,28 @@ pub(crate) fn deprecated_log_warn(checker: &mut Checker, call: &ExprCall) {
         _ => return,
     }
 
-    checker
+    let mut diagnostic = Diagnostic::new(DeprecatedLogWarn, call.func.range());
-        .diagnostics
+    if checker.settings.preview.is_enabled() {
-        .push(Diagnostic::new(DeprecatedLogWarn, call.func.range()));
+        match call.func.as_ref() {
+            Expr::Attribute(ast::ExprAttribute { attr, .. }) => {
+                diagnostic.set_fix(Fix::safe_edit(Edit::range_replacement(
+                    "warning".to_string(),
+                    attr.range(),
+                )));
+            }
+            Expr::Name(_) => {
+                diagnostic.try_set_fix(|| {
+                    let (import_edit, binding) = checker.importer().get_or_import_symbol(
+                        &ImportRequest::import("logging", "warning"),
+                        call.start(),
+                        checker.semantic(),
+                    )?;
+                    let name_edit = Edit::range_replacement(binding, call.func.range());
+                    Ok(Fix::safe_edits(import_edit, [name_edit]))
+                });
+            }
+            _ => {}
+        }
+    }
+    checker.diagnostics.push(diagnostic);
 }

crates/ruff_linter/src/rules/pygrep_hooks/snapshots/ruff_linter__rules__pygrep_hooks__tests__PGH002_PGH002_1.py.snap

@@ -9,6 +9,7 @@ PGH002_1.py:4:1: PGH002 `warn` is deprecated in favor of `warning`
   | ^^^^^^^^^^^^ PGH002
 5 | warn("not ok")
   |
+  = help: Replace with `warning`
 
 PGH002_1.py:5:1: PGH002 `warn` is deprecated in favor of `warning`
   |
@@ -18,6 +19,7 @@ PGH002_1.py:5:1: PGH002 `warn` is deprecated in favor of `warning`
 6 | 
 7 | logger = logging.getLogger(__name__)
   |
+  = help: Replace with `warning`
 
 PGH002_1.py:8:1: PGH002 `warn` is deprecated in favor of `warning`
   |
@@ -25,5 +27,6 @@ PGH002_1.py:8:1: PGH002 `warn` is deprecated in favor of `warning`
 8 | logger.warn("this is not ok")
   | ^^^^^^^^^^^ PGH002
   |
+  = help: Replace with `warning`
 
 

crates/ruff_linter/src/rules/pygrep_hooks/snapshots/ruff_linter__rules__pygrep_hooks__tests__preview__PGH002_PGH002_1.py.snap

@@ -0,0 +1,59 @@
+---
+source: crates/ruff_linter/src/rules/pygrep_hooks/mod.rs
+---
+PGH002_1.py:4:1: PGH002 [*] `warn` is deprecated in favor of `warning`
+  |
+2 | from logging import warn
+3 | 
+4 | logging.warn("this is not ok")
+  | ^^^^^^^^^^^^ PGH002
+5 | warn("not ok")
+  |
+  = help: Replace with `warning`
+
+ℹ Safe fix
+1 1 | import logging
+2 2 | from logging import warn
+3 3 | 
+4   |-logging.warn("this is not ok")
+  4 |+logging.warning("this is not ok")
+5 5 | warn("not ok")
+6 6 | 
+7 7 | logger = logging.getLogger(__name__)
+
+PGH002_1.py:5:1: PGH002 [*] `warn` is deprecated in favor of `warning`
+  |
+4 | logging.warn("this is not ok")
+5 | warn("not ok")
+  | ^^^^ PGH002
+6 | 
+7 | logger = logging.getLogger(__name__)
+  |
+  = help: Replace with `warning`
+
+ℹ Safe fix
+2 2 | from logging import warn
+3 3 | 
+4 4 | logging.warn("this is not ok")
+5   |-warn("not ok")
+  5 |+logging.warning("not ok")
+6 6 | 
+7 7 | logger = logging.getLogger(__name__)
+8 8 | logger.warn("this is not ok")
+
+PGH002_1.py:8:1: PGH002 [*] `warn` is deprecated in favor of `warning`
+  |
+7 | logger = logging.getLogger(__name__)
+8 | logger.warn("this is not ok")
+  | ^^^^^^^^^^^ PGH002
+  |
+  = help: Replace with `warning`
+
+ℹ Safe fix
+5 5 | warn("not ok")
+6 6 | 
+7 7 | logger = logging.getLogger(__name__)
+8   |-logger.warn("this is not ok")
+  8 |+logger.warning("this is not ok")
+
+