Avoid invalid combination of force-sort-within-types and `lines-bet…

…ween-types` (#9041)

Closes #8792.

crates/ruff_linter/resources/test/fixtures/isort/force_sort_within_sections_lines_between.py

@@ -0,0 +1,4 @@
+from a import x
+import b
+from c import y
+import d

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

@@ -200,6 +200,7 @@ fn format_import_block(
                     // Add a blank lines between direct and from imports.
                     if settings.from_first
                         && lines_between_types > 0
+                        && !settings.force_sort_within_sections
                         && line_insertion == Some(LineInsertion::Necessary)
                     {
                         for _ in 0..lines_between_types {
@@ -225,6 +226,7 @@ fn format_import_block(
                     // Add a blank lines between direct and from imports.
                     if !settings.from_first
                         && lines_between_types > 0
+                        && !settings.force_sort_within_sections
                         && line_insertion == Some(LineInsertion::Necessary)
                     {
                         for _ in 0..lines_between_types {
@@ -722,6 +724,26 @@ mod tests {
         Ok(())
     }
 
+    #[test_case(Path::new("force_sort_within_sections_lines_between.py"))]
+    fn force_sort_within_sections_lines_between(path: &Path) -> Result<()> {
+        let snapshot = format!("force_sort_within_sections_{}", path.to_string_lossy());
+        let mut diagnostics = test_path(
+            Path::new("isort").join(path).as_path(),
+            &LinterSettings {
+                isort: super::settings::Settings {
+                    force_sort_within_sections: true,
+                    lines_between_types: 2,
+                    ..super::settings::Settings::default()
+                },
+                src: vec![test_resource_path("fixtures/isort")],
+                ..LinterSettings::for_rule(Rule::UnsortedImports)
+            },
+        )?;
+        diagnostics.sort_by_key(Ranged::start);
+        assert_messages!(snapshot, diagnostics);
+        Ok(())
+    }
+
     #[test_case(Path::new("comment.py"))]
     #[test_case(Path::new("comments_and_newlines.py"))]
     #[test_case(Path::new("docstring.py"))]

crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__force_sort_within_sections_force_sort_within_sections_lines_between.py.snap

@@ -0,0 +1,4 @@
+---
+source: crates/ruff_linter/src/rules/isort/mod.rs
+---
+

crates/ruff_workspace/src/options.rs

@@ -2109,6 +2109,13 @@ impl IsortOptions {
             warn_user_once!("`sections` is ignored when `no-sections` is set to `true`");
         }
 
+        // Verify that if `force_sort_within_sections` is `True`, then `lines_between_types` is set to `0`.
+        let force_sort_within_sections = self.force_sort_within_sections.unwrap_or_default();
+        let lines_between_types = self.lines_between_types.unwrap_or_default();
+        if force_sort_within_sections && lines_between_types != 0 {
+            warn_user_once!("`lines-between-types` is ignored when `force-sort-within-sections` is set to `true`");
+        }
+
         // Extract any configuration options that deal with user-defined sections.
         let mut section_order: Vec<_> = self
             .section_order
@@ -2240,7 +2247,7 @@ impl IsortOptions {
             required_imports: BTreeSet::from_iter(self.required_imports.unwrap_or_default()),
             combine_as_imports: self.combine_as_imports.unwrap_or(false),
             force_single_line: self.force_single_line.unwrap_or(false),
-            force_sort_within_sections: self.force_sort_within_sections.unwrap_or(false),
+            force_sort_within_sections,
             case_sensitive: self.case_sensitive.unwrap_or(false),
             force_wrap_aliases: self.force_wrap_aliases.unwrap_or(false),
             detect_same_package: self.detect_same_package.unwrap_or(true),
@@ -2263,7 +2270,7 @@ impl IsortOptions {
             variables: BTreeSet::from_iter(self.variables.unwrap_or_default()),
             no_lines_before: BTreeSet::from_iter(no_lines_before),
             lines_after_imports: self.lines_after_imports.unwrap_or(-1),
-            lines_between_types: self.lines_between_types.unwrap_or_default(),
+            lines_between_types,
             forced_separate: Vec::from_iter(self.forced_separate.unwrap_or_default()),
             section_order,
             no_sections,