fix(eval): load MSMARCO remote qrels when dataset_dir is not set

When no dataset_dir is given, MSMARCOEvalDataLoader._load_remote_qrels
reads qrels without saving them, but the check on qrels_save_path was
inverted. For the dl19/dl20 splits (and document dev) it skipped the
downloaded TREC file and iterated the undefined HF `qrels`, raising
UnboundLocalError; for passage dev it tried to open(None).

Flip the condition to match the save_dir branch and add a regression
test that mocks the download.

Author: MohammadHijjawi97

FlagEmbedding/evaluation/msmarco/data_loader.py

@@ -179,7 +179,7 @@ def _load_remote_qrels(
             logging.info(f"{self.eval_name} {dataset_name} qrels saved to {save_path}")
         else:
             qrels_dict = {}
-            if qrels_save_path is None:
+            if qrels_save_path is not None:
                 with open(qrels_save_path, "r", encoding="utf-8") as f:
                     for line in tqdm(f.readlines(), desc="Loading qrels"):
                         qid, _, docid, rel = line.strip().split()

tests/README.md

@@ -10,6 +10,7 @@ This directory contains tests for the FlagEmbedding library, including compatibi
 - `test_tokenizer_pad_compat.py`: Tests normalization of sorted per-example tokenized records before `tokenizer.pad`, including the local BGE reranker tokenizer when available.
 - `test_infer_embedder_basic.py`: Tests basic functionality of BGE embedder models with a small public checkpoint.
 - `test_infer_reranker_basic.py`: Tests basic functionality of reranker models.
+- `test_msmarco_data_loader.py`: Tests loading MSMARCO qrels from remote without a local `dataset_dir`, using a mocked download.
 
 ## Running Tests
 

tests/test_msmarco_data_loader.py

@@ -0,0 +1,23 @@
+"""
+Test loading MSMARCO qrels from remote without a local ``dataset_dir``.
+
+The download is mocked with a tiny TREC-style qrels file, so no network access is needed.
+"""
+
+import pytest
+
+from FlagEmbedding.evaluation.msmarco import MSMARCOEvalDataLoader
+
+
+@pytest.mark.parametrize("dataset_name", ["passage", "document"])
+@pytest.mark.parametrize("split", ["dl19", "dl20"])
+def test_load_remote_qrels_without_save_dir(tmp_path, monkeypatch, dataset_name, split):
+    qrels_file = tmp_path / "qrels.txt"
+    qrels_file.write_text("1 Q0 doc-1 2\n1 Q0 doc-2 0\n2 Q0 doc-3 1\n", encoding="utf-8")
+
+    data_loader = MSMARCOEvalDataLoader(eval_name="msmarco", cache_dir=str(tmp_path))
+    monkeypatch.setattr(data_loader, "_download_file", lambda *args, **kwargs: str(qrels_file))
+
+    qrels = data_loader.load_qrels(dataset_name=dataset_name, split=split)
+
+    assert dict(qrels) == {"1": {"doc-1": 2, "doc-2": 0}, "2": {"doc-3": 1}}