fix(runtime): skip a relative import path entry when the working directory is gone

The import hook read the working directory outside its error handling,
so after the directory was deleted every import through a relative
search path entry raised FileNotFoundError. The entry is skipped again,
as before the hook keyed entries by directory. A SQL macro lexer test
now names the raw-string prefix rules it uses.

Author: kvlonge

crates/sqlbuild-analysis/src/sql_macros/tests/test_lexical_rules.rs

@@ -31,7 +31,7 @@ fn given_adapter_lexical_rules_when_finding_sql_macro_calls_then_strings_end_whe
             expected_calls: &["order_total"],
         },
         LexicalRulesCallsTestCase {
-            description: "a raw string ending in a backslash on BigQuery",
+            description: "a raw string ending in a backslash under raw-string prefix rules",
             syntax: raw_prefix_rules(),
             sql: "SELECT r'C:\\' AS path, @sql.order_total(1) AS b",
             expected_calls: &["order_total"],

src/sqlbuild/runtime/user_code/classes/user_code_finder.py

@@ -60,7 +60,10 @@ def _is_project_entry(self, entry: str) -> bool:
         if roots != self._entry_roots:
             self._project_entries = {}
             self._entry_roots = roots
-        directory: str = "" if os.path.isabs(entry) else os.getcwd()
+        try:
+            directory: str = "" if os.path.isabs(entry) else os.getcwd()
+        except OSError:
+            return False
         known: bool | None = self._project_entries.get((entry, directory))
         if known is not None:
             return known

tests/unit/src/sqlbuild/runtime/user_code/classes/_test_types.py

@@ -21,3 +21,12 @@ class FinderWorkingDirectoryTestCase:
     first_directory: str
     second_directory: str
     expected_source_only: tuple[bool, bool]
+
+
+@dataclass(frozen=True)
+class FinderDeletedDirectoryTestCase:
+    """A lookup while the working directory, on the search path as "", has been deleted."""
+
+    description: str
+    module_name: str
+    expected_spec: None = None

tests/unit/src/sqlbuild/runtime/user_code/classes/test_user_code_finder.py

@@ -9,6 +9,7 @@
 from sqlbuild.runtime.user_code.classes.source_only_loader import SourceOnlyLoader
 from sqlbuild.runtime.user_code.classes.user_code_finder import UserCodeFinder
 from tests.unit.src.sqlbuild.runtime.user_code.classes._test_types import (
+    FinderDeletedDirectoryTestCase,
     FinderSpecTestCase,
     FinderWorkingDirectoryTestCase,
 )
@@ -98,5 +99,36 @@ def test_given_working_directory_entry_when_directory_changes_then_finder_follow
     ) == test_case.expected_source_only
 
 
+@pytest.mark.parametrize(
+    "test_case",
+    [
+        FinderDeletedDirectoryTestCase(
+            description="a project module is left to normal import", module_name="order_rules"
+        ),
+        FinderDeletedDirectoryTestCase(
+            description="a standard-library module is left to normal import", module_name="json"
+        ),
+    ],
+    ids=lambda case: case.description,
+)
+def test_given_deleted_working_directory_when_finding_spec_then_relative_entry_is_skipped(
+    test_case: FinderDeletedDirectoryTestCase, tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    project: Path = tmp_path / "project"
+    project.mkdir()
+    _ = (project / "order_rules.py").write_text("LIMIT: int = 1\n", encoding="utf-8")
+    deleted: Path = tmp_path / "deleted"
+    deleted.mkdir()
+    monkeypatch.setattr(sys, "path", ["", *sys.path])
+    finder: UserCodeFinder = UserCodeFinder()
+    finder.roots.add(project.resolve())
+    monkeypatch.chdir(deleted)
+    deleted.rmdir()
+
+    spec: ModuleSpec | None = finder.find_spec(test_case.module_name)
+
+    assert spec == test_case.expected_spec
+
+
 if __name__ == "__main__":
     raise SystemExit(pytest.main([__file__, "-n", "auto", "--dist", "loadfile"]))