Typing tuning

- Guard all imports in `robot.model.visitor` with `if TYPE_CHECKING`
  to avoid cyclic imports with modules needing to import `SuiteVisitor`.

- Modules anyway needing `if TYPE_CHECKING`, and only using `SuiteVisitor`
  for typing, still import it conditionally. We may consider using
  `if TYPE_CHECKING` with all imports needed only typing purposes.

- `dict[str, Any]` typing wtih `to_dict`. Also with `data` used internally
  to avoid errors with VScode.

- Use `from .mod import X` insted of `from robot.mod import X` style in
  imports consisently. `visitor` is an exception because importing
  everything from `robot.model` in one go is just too convenient.

src/robot/model/keyword.py

@@ -13,16 +13,16 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
-from typing import Sequence, TYPE_CHECKING, Type
+from typing import Any, Sequence, Type, TYPE_CHECKING
 import warnings
 
 from .body import Body, BodyItem
 from .itemlist import ItemList
 
 if TYPE_CHECKING:
-    from robot.model.testcase import TestCase
-    from robot.model.testsuite import TestSuite
-    from robot.model.visitor import SuiteVisitor
+    from .testcase import TestCase
+    from .testsuite import TestSuite
+    from .visitor import SuiteVisitor
 
 
 @Body.register
@@ -64,8 +64,8 @@ def __str__(self) -> str:
         parts = list(self.assign) + [self.name] + list(self.args)
         return '    '.join(str(p) for p in parts)
 
-    def to_dict(self) -> dict:
-        data: 'dict[str,list|str]' =  {'name': self.name}
+    def to_dict(self) -> 'dict[str, Any]':
+        data: 'dict[str, Any]' = {'name': self.name}
         if self.args:
             data['args'] = list(self.args)
         if self.assign:

src/robot/model/testcase.py

@@ -14,7 +14,7 @@
 #  limitations under the License.
 
 from pathlib import Path
-from typing import Iterable, Mapping, Sequence, TYPE_CHECKING, Type
+from typing import Any, Iterable, Mapping, Sequence, Type, TYPE_CHECKING
 
 from robot.utils import setter
 
@@ -26,8 +26,8 @@
 from .tags import Tags
 
 if TYPE_CHECKING:
-    from robot.model.testsuite import TestSuite
-    from robot.model.visitor import SuiteVisitor
+    from .testsuite import TestSuite
+    from .visitor import SuiteVisitor
 
 
 class TestCase(ModelObject):
@@ -179,9 +179,8 @@ def visit(self, visitor: 'SuiteVisitor'):
     def __str__(self) -> str:
         return self.name
 
-    def to_dict(self) -> dict:
-        data = {}
-        data['name'] = self.name
+    def to_dict(self) -> 'dict[str, Any]':
+        data: 'dict[str, Any]' = {'name': self.name}
         if self.doc:
             data['doc'] = self.doc
         if self.tags:

src/robot/model/testsuite.py

@@ -15,7 +15,7 @@
 
 from collections.abc import Mapping
 from pathlib import Path
-from typing import Iterator, Sequence, Type, TYPE_CHECKING
+from typing import Any, Iterator, Sequence, Type
 
 from robot.utils import setter
 
@@ -28,9 +28,7 @@
 from .modelobject import ModelObject
 from .tagsetter import TagSetter
 from .testcase import TestCase, TestCases
-
-if TYPE_CHECKING:
-    from robot.model.visitor import SuiteVisitor
+from .visitor import SuiteVisitor
 
 
 class TestSuite(ModelObject):
@@ -303,16 +301,15 @@ def remove_empty_suites(self, preserve_direct_children: bool = False):
         """Removes all child suites not containing any tests, recursively."""
         self.visit(EmptySuiteRemover(preserve_direct_children))
 
-    def visit(self, visitor: 'SuiteVisitor'):
+    def visit(self, visitor: SuiteVisitor):
         """:mod:`Visitor interface <robot.model.visitor>` entry-point."""
         visitor.visit_suite(self)
 
     def __str__(self) -> str:
         return self.name
 
-    def to_dict(self) -> dict:
-        data = {}
-        data['name'] = self.name
+    def to_dict(self) -> 'dict[str, Any]':
+        data: 'dict[str, Any]' = {'name': self.name}
         if self.doc:
             data['doc'] = self.doc
         if self.metadata: