perf(robot): use file_id tuples instead of os.path.samefile for path comparison

Replace repeated os.path.samefile() calls (2x stat per call) in namespace
import loops with pre-computed (st_dev, st_ino) tuple comparisons.

- Add FileId type, file_id() and same_file_id() to core utils
- Add lazy source_id property to LibraryDoc (excluded from pickle)
- Pre-compute source_id on Namespace init
- Compute file_id once per find_resource result instead of per-iteration

Author: d-biehl

packages/core/src/robotcode/core/utils/path.py

@@ -2,7 +2,7 @@
 import re
 import sys
 from pathlib import Path
-from typing import Any, Union
+from typing import Any, Optional, Tuple, Union
 
 
 def path_is_relative_to(
@@ -61,8 +61,30 @@ def normalized_path_full(path: Union[str, "os.PathLike[str]"]) -> Path:
     return Path(*parents)
 
 
+FileId = Tuple[int, int]
+
+
+def file_id(path: Union[str, "os.PathLike[str]", Path]) -> Optional[FileId]:
+    """Return the (st_dev, st_ino) tuple for *path*, or ``None`` on error."""
+    try:
+        st = os.stat(path)
+        return (st.st_dev, st.st_ino)
+    except OSError:
+        return None
+
+
 def same_file(path1: Union[str, "os.PathLike[str]", Path], path2: Union[str, "os.PathLike[str]", Path]) -> bool:
     try:
         return os.path.samefile(path1, path2)
     except OSError:
         return False
+
+
+def same_file_id(
+    id1: Optional[FileId],
+    id2: Optional[FileId],
+) -> bool:
+    """Compare two :func:`file_id` values. ``None`` never matches anything."""
+    if id1 is None or id2 is None:
+        return False
+    return id1 == id2

packages/robot/src/robotcode/robot/diagnostics/library_doc.py

@@ -62,7 +62,7 @@
 from robot.variables.finders import VariableFinder
 from robot.variables.replacer import VariableReplacer
 from robotcode.core.lsp.types import Position, Range
-from robotcode.core.utils.path import normalized_path
+from robotcode.core.utils.path import FileId, file_id, normalized_path
 
 from ..utils import get_robot_version
 from ..utils.ast import (
@@ -1023,6 +1023,13 @@ class LibraryDoc:
     stdout: Optional[str] = field(default=None, compare=False)
     has_listener: Optional[bool] = None
     library_type: Optional[LibraryType] = None
+    _source_id: Optional[FileId] = field(default=None, init=False, compare=False, hash=False, repr=False)
+
+    @property
+    def source_id(self) -> Optional[FileId]:
+        if self._source_id is None and self.source is not None:
+            self._source_id = file_id(self.source)
+        return self._source_id
 
     @property
     def inits(self) -> KeywordStore:
@@ -1053,6 +1060,17 @@ def __post_init__(self) -> None:
         self._update_keywords(self._inits)
         self._update_keywords(self._keywords)
 
+    def _all_slots(self) -> Iterator[str]:
+        for cls in type(self).__mro__:
+            yield from getattr(cls, "__slots__", ())
+
+    def __getstate__(self) -> Dict[str, Any]:
+        return {slot: getattr(self, slot) for slot in self._all_slots() if slot != "_source_id"}
+
+    def __setstate__(self, state: Dict[str, Any]) -> None:
+        for slot in self._all_slots():
+            object.__setattr__(self, slot, state.get(slot, None))
+
     def __hash__(self) -> int:
         return hash(
             (

packages/robot/src/robotcode/robot/diagnostics/namespace.py

@@ -44,7 +44,7 @@
 from robotcode.core.text_document import TextDocument
 from robotcode.core.uri import Uri
 from robotcode.core.utils.logging import LoggingDescriptor
-from robotcode.core.utils.path import same_file
+from robotcode.core.utils.path import file_id, same_file_id
 
 from ..utils import get_robot_version
 from ..utils.ast import (
@@ -713,6 +713,7 @@ def __init__(
 
         self.model = model
         self.source = source
+        self.source_id = file_id(source)
         self._document = weakref.ref(document) if document is not None else None
         self.document_type: Optional[DocumentType] = document_type
         self.languages = languages
@@ -1296,12 +1297,13 @@ def _import(
                     raise NameSpaceError("Resource setting requires value.")
 
                 source = self.imports_manager.find_resource(value.name, base_dir, variables=variables)
+                source_fid = file_id(source)
 
                 allread_imported_resource = next(
                     (
                         v
                         for k, v in self._resources.items()
-                        if v.library_doc.source is not None and same_file(v.library_doc.source, source)
+                        if v.library_doc.source_id is not None and same_file_id(v.library_doc.source_id, source_fid)
                     ),
                     None,
                 )
@@ -1330,7 +1332,7 @@ def _import(
                         )
                     return None
 
-                if same_file(self.source, source):
+                if same_file_id(self.source_id, source_fid):
                     if parent_import:
                         self.append_diagnostics(
                             range=parent_import.range,
@@ -1609,12 +1611,8 @@ def _import_imports(
                                 e
                                 for e in self._variables_imports.values()
                                 if (
-                                    (
-                                        e.library_doc.source is not None
-                                        and entry.library_doc.source is not None
-                                        and same_file(e.library_doc.source, entry.library_doc.source)
-                                    )
-                                    or (e.library_doc.source is None and entry.library_doc.source is None)
+                                    same_file_id(e.library_doc.source_id, entry.library_doc.source_id)
+                                    or (e.library_doc.source_id is None and entry.library_doc.source_id is None)
                                 )
                                 and e.alias == entry.alias
                                 and e.args == entry.args
@@ -1681,12 +1679,8 @@ def _import_imports(
                                 e
                                 for e in self._libraries.values()
                                 if (
-                                    (
-                                        e.library_doc.source is not None
-                                        and entry.library_doc.source is not None
-                                        and same_file(e.library_doc.source, entry.library_doc.source)
-                                    )
-                                    or (e.library_doc.source is None and entry.library_doc.source is None)
+                                    same_file_id(e.library_doc.source_id, entry.library_doc.source_id)
+                                    or (e.library_doc.source_id is None and entry.library_doc.source_id is None)
                                 )
                                 and e.library_doc.member_name == entry.library_doc.member_name
                                 and e.alias == entry.alias