Ensure that from-style imports are always ordered first in __future__ (#9039)

Closes https://github.com/astral-sh/ruff/issues/8823.

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

@@ -0,0 +1,2 @@
+import __future__
+from __future__ import annotations

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

@@ -0,0 +1,2 @@
+import __future__
+from __future__ import annotations

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

@@ -180,7 +180,7 @@ fn format_import_block(
             continue;
         };
 
-        let imports = order_imports(import_block, settings);
+        let imports = order_imports(import_block, import_section, settings);
 
         // Add a blank line between every section.
         if is_first_block {
@@ -291,6 +291,7 @@ mod tests {
     #[test_case(Path::new("force_sort_within_sections.py"))]
     #[test_case(Path::new("force_to_top.py"))]
     #[test_case(Path::new("force_wrap_aliases.py"))]
+    #[test_case(Path::new("future_from.py"))]
     #[test_case(Path::new("if_elif_else.py"))]
     #[test_case(Path::new("import_from_after_import.py"))]
     #[test_case(Path::new("inline_comments.py"))]
@@ -701,6 +702,7 @@ mod tests {
 
     #[test_case(Path::new("force_sort_within_sections.py"))]
     #[test_case(Path::new("force_sort_within_sections_with_as_names.py"))]
+    #[test_case(Path::new("force_sort_within_sections_future.py"))]
     fn force_sort_within_sections(path: &Path) -> Result<()> {
         let snapshot = format!("force_sort_within_sections_{}", path.to_string_lossy());
         let mut diagnostics = test_path(

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

@@ -1,4 +1,5 @@
 use crate::rules::isort::sorting::ImportStyle;
+use crate::rules::isort::{ImportSection, ImportType};
 use itertools::Itertools;
 
 use super::settings::Settings;
@@ -8,6 +9,7 @@ use super::types::{AliasData, CommentSet, ImportBlock, ImportFromStatement};
 
 pub(crate) fn order_imports<'a>(
     block: ImportBlock<'a>,
+    section: &ImportSection,
     settings: &Settings,
 ) -> Vec<EitherImport<'a>> {
     let straight_imports = block.import.into_iter();
@@ -52,7 +54,35 @@ pub(crate) fn order_imports<'a>(
                 },
             );
 
-    let ordered_imports = if settings.force_sort_within_sections {
+    let ordered_imports = if matches!(section, ImportSection::Known(ImportType::Future)) {
+        from_imports
+            .sorted_by_cached_key(|(import_from, _, _, aliases)| {
+                ModuleKey::from_module(
+                    import_from.module,
+                    None,
+                    import_from.level,
+                    aliases.first().map(|(alias, _)| (alias.name, alias.asname)),
+                    ImportStyle::From,
+                    settings,
+                )
+            })
+            .map(ImportFrom)
+            .chain(
+                straight_imports
+                    .sorted_by_cached_key(|(alias, _)| {
+                        ModuleKey::from_module(
+                            Some(alias.name),
+                            alias.asname,
+                            None,
+                            None,
+                            ImportStyle::Straight,
+                            settings,
+                        )
+                    })
+                    .map(Import),
+            )
+            .collect()
+    } else if settings.force_sort_within_sections {
         straight_imports
             .map(Import)
             .chain(from_imports.map(ImportFrom))

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

@@ -0,0 +1,16 @@
+---
+source: crates/ruff_linter/src/rules/isort/mod.rs
+---
+force_sort_within_sections_future.py:1:1: I001 [*] Import block is un-sorted or un-formatted
+  |
+1 | / import __future__
+2 | | from __future__ import annotations
+  |
+  = help: Organize imports
+
+ℹ Safe fix
+  1 |+from __future__ import annotations
+1 2 | import __future__
+2   |-from __future__ import annotations
+
+

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

@@ -0,0 +1,16 @@
+---
+source: crates/ruff_linter/src/rules/isort/mod.rs
+---
+future_from.py:1:1: I001 [*] Import block is un-sorted or un-formatted
+  |
+1 | / import __future__
+2 | | from __future__ import annotations
+  |
+  = help: Organize imports
+
+ℹ Safe fix
+  1 |+from __future__ import annotations
+1 2 | import __future__
+2   |-from __future__ import annotations
+
+