Fix imports ordering (#841)

tests/formats/dataclass/test_filters.py

@@ -877,12 +877,21 @@ def test_default_imports_with_module(self):
         self.assertEqual(expected, self.filters.default_imports(output))
 
     def test_default_imports_with_annotations(self):
-        config = GeneratorConfig()
-        config.output.postponed_annotations = True
-        filters = Filters(config)
+        self.filters.postponed_annotations = True
 
         expected = "from __future__ import annotations"
-        self.assertEqual(expected, filters.default_imports(""))
+        self.assertEqual(expected, self.filters.default_imports(""))
+
+    def test_default_imports_ordering(self):
+        self.filters.postponed_annotations = True
+        self.filters.import_patterns["attrs"] = {"__module__": ["@attrs.s"]}
+
+        expected = (
+            "from __future__ import annotations\n"
+            "import attrs\n"
+            "from dataclasses import dataclass"
+        )
+        self.assertEqual(expected, self.filters.default_imports("@dataclass @attrs.s"))
 
     def test_format_metadata(self):
         data = dict(

xsdata/formats/dataclass/filters.py

@@ -764,11 +764,8 @@ def constant_value(self, attr: Attr) -> str:
 
     def default_imports(self, output: str) -> str:
         """Generate the default imports for the given package output."""
-        result = []
-
-        if self.postponed_annotations:
-            result.append("from __future__ import annotations")
-
+        module_imports = set()
+        func_imports = set()
         for library, types in self.import_patterns.items():
             names = [
                 name
@@ -777,11 +774,15 @@ def default_imports(self, output: str) -> str:
             ]
 
             if len(names) == 1 and names[0] == "__module__":
-                result.append(f"import {library}")
+                module_imports.add(f"import {library}")
             elif names:
-                result.append(f"from {library} import {', '.join(names)}")
+                func_imports.add(f"from {library} import {', '.join(names)}")
+
+        imports = sorted(module_imports) + sorted(func_imports)
+        if self.postponed_annotations:
+            imports.insert(0, "from __future__ import annotations")
 
-        return "\n".join(sorted(result))
+        return "\n".join(imports)
 
     @classmethod
     def build_import_patterns(cls) -> Dict[str, Dict]: