Fixed diagnostics files uri handling, added low-level tests

test/solidlsp/util/diagnostics.py

@@ -0,0 +1,19 @@
+from collections.abc import Sequence
+
+from solidlsp import SolidLanguageServer
+
+
+def assert_file_diagnostics(
+    language_server: SolidLanguageServer,
+    relative_file_path: str,
+    expected_message_fragments: Sequence[str],
+    min_count: int = 1,
+) -> None:
+    diagnostics = language_server.request_text_document_diagnostics(relative_file_path, min_severity=1)
+
+    assert isinstance(diagnostics, list), diagnostics
+    assert len(diagnostics) >= min_count, diagnostics
+
+    diagnostic_messages = [diagnostic["message"] for diagnostic in diagnostics]
+    for fragment in expected_message_fragments:
+        assert any(fragment in message for message in diagnostic_messages), diagnostic_messages