Merge pull request #2458 from skv0zsneg/issue/1882

Fix edge case of `__future__` import.

Author: DanielNoord

isort/output.py

@@ -12,6 +12,8 @@
 from .settings import DEFAULT_CONFIG, Config
 
 
+# Ignore DeepSource cyclomatic complexity check for this function.
+# skipcq: PY-R1000
 def sorted_imports(
     parsed: parse.ParsedContent,
     config: Config = DEFAULT_CONFIG,
@@ -88,7 +90,7 @@ def sorted_imports(
         lines_between = [""] * (
             config.lines_between_types if from_modules and straight_modules else 0
         )
-        if config.from_first:
+        if config.from_first or section == "FUTURE":
             section_output = from_imports + lines_between + straight_imports
         else:
             section_output = straight_imports + lines_between + from_imports

tests/unit/test_isort.py

@@ -5640,3 +5640,74 @@ def test_noqa_multiline_hanging_indent() -> None:
     )
     output = isort.code(test_input, line_length=120, multi_line_output=WrapModes.HANGING_INDENT)
     assert output == test_input
+
+
+@pytest.mark.parametrize(
+    (
+        "actual_imports",
+        "expected_sort",
+    ),
+    [
+        (
+            ("from __future__ import annotations\nimport __future__\n"),
+            ("from __future__ import annotations\nimport __future__\n"),
+        ),
+        (
+            (
+                "import __future__\n\n"
+                "from __future__ import generator_stop\n"
+                "from __future__ import annotations\n\n"
+                "from concurrent.futures import ThreadPoolExecutor\n\n"
+            ),
+            (
+                "from __future__ import annotations, generator_stop\n"
+                "import __future__\n\n"
+                "from concurrent.futures import ThreadPoolExecutor\n"
+            ),
+        ),
+        (
+            ("from __future__ import annotations\nimport sys\n"),
+            ("from __future__ import annotations\n\nimport sys\n"),
+        ),
+        (("import __future__\nimport sys\n"), ("import __future__\n\nimport sys\n")),
+        (
+            ("import __future__ as future\nfrom __future__ import annotations\n"),
+            ("from __future__ import annotations\nimport __future__ as future\n"),
+        ),
+        (
+            ("# Copyright 2026\nimport __future__\nfrom __future__ import annotations\n"),
+            ("# Copyright 2026\nfrom __future__ import annotations\nimport __future__\n"),
+        ),
+        (
+            ("import __future__\nfrom __future__ import *\n"),
+            ("from __future__ import *\nimport __future__\n"),
+        ),
+        (
+            (
+                "from __future__ import annotations\n"
+                "import __future__\n"
+                "from __future__ import annotations\n"
+            ),
+            ("from __future__ import annotations\nimport __future__\n"),
+        ),
+        (
+            (
+                "import sys\n"
+                "from __future__ import annotations\n"
+                "import os\n"
+                "import __future__\n"
+                "from pathlib import Path\n"
+            ),
+            (
+                "from __future__ import annotations\n"
+                "import __future__\n\n"
+                "import os\n"
+                "import sys\n"
+                "from pathlib import Path\n"
+            ),
+        ),
+    ],
+)
+def test_dunder_future_import(actual_imports: str, expected_sort: str) -> None:
+    output = isort.code(actual_imports)
+    assert output == expected_sort