Fix autofix conflict between D209 and D400 (#3564)

crates/ruff/resources/test/fixtures/pydocstyle/D209_D400.py

@@ -0,0 +1,3 @@
+def lorem():
+    """lorem ipsum dolor sit amet consectetur adipiscing elit
+    sed do eiusmod tempor incididunt ut labore et dolore magna aliqua"""

crates/ruff/src/autofix/mod.rs

@@ -9,7 +9,7 @@ use ruff_python_ast::source_code::Locator;
 use ruff_python_ast::types::Range;
 
 use crate::linter::FixTable;
-use crate::registry::AsRule;
+use crate::registry::{AsRule, Rule};
 
 pub mod helpers;
 
@@ -39,7 +39,7 @@ fn apply_fixes<'a>(
                 .as_ref()
                 .map(|fix| (diagnostic.kind.rule(), fix))
         })
-        .sorted_by_key(|(.., fix)| fix.location)
+        .sorted_by(|(rule1, fix1), (rule2, fix2)| cmp_fix(*rule1, *rule2, fix1, fix2))
     {
         // If we already applied an identical fix as part of another correction, skip
         // any re-application.
@@ -92,6 +92,18 @@ pub(crate) fn apply_fix(fix: &Fix, locator: &Locator) -> String {
     output
 }
 
+/// Compare two fixes.
+fn cmp_fix(rule1: Rule, rule2: Rule, fix1: &Fix, fix2: &Fix) -> std::cmp::Ordering {
+    fix1.location
+        .cmp(&fix2.location)
+        .then_with(|| match (&rule1, &rule2) {
+            // Apply `EndsInPeriod` fixes before `NewLineAfterLastParagraph` fixes.
+            (Rule::EndsInPeriod, Rule::NewLineAfterLastParagraph) => std::cmp::Ordering::Less,
+            (Rule::NewLineAfterLastParagraph, Rule::EndsInPeriod) => std::cmp::Ordering::Greater,
+            _ => std::cmp::Ordering::Equal,
+        })
+}
+
 #[cfg(test)]
 mod tests {
     use rustpython_parser::ast::Location;

crates/ruff/src/rules/pydocstyle/mod.rs

@@ -153,4 +153,14 @@ mod tests {
         assert_yaml_snapshot!(diagnostics);
         Ok(())
     }
+
+    #[test]
+    fn d209_d400() -> Result<()> {
+        let diagnostics = test_path(
+            Path::new("pydocstyle/D209_D400.py"),
+            &settings::Settings::for_rules([Rule::NewLineAfterLastParagraph, Rule::EndsInPeriod]),
+        )?;
+        assert_yaml_snapshot!(diagnostics);
+        Ok(())
+    }
 }

crates/ruff/src/rules/pydocstyle/snapshots/ruff__rules__pydocstyle__tests__d209_d400.snap

@@ -0,0 +1,45 @@
+---
+source: crates/ruff/src/rules/pydocstyle/mod.rs
+expression: diagnostics
+---
+- kind:
+    name: NewLineAfterLastParagraph
+    body: Multi-line docstring closing quotes should be on a separate line
+    suggestion: Move closing quotes to new line
+    fixable: true
+  location:
+    row: 2
+    column: 4
+  end_location:
+    row: 3
+    column: 72
+  fix:
+    content: "\n    "
+    location:
+      row: 3
+      column: 69
+    end_location:
+      row: 3
+      column: 69
+  parent: ~
+- kind:
+    name: EndsInPeriod
+    body: First line should end with a period
+    suggestion: Add period
+    fixable: true
+  location:
+    row: 2
+    column: 4
+  end_location:
+    row: 3
+    column: 72
+  fix:
+    content: "."
+    location:
+      row: 3
+      column: 69
+    end_location:
+      row: 3
+      column: 69
+  parent: ~
+