From 9dae986d75a309893d6dda032d76cfef50bec4d0 Mon Sep 17 00:00:00 2001
From: Ziyang Guo <121015044+RerankerGuo@users.noreply.github.com>
Date: Thu, 13 Aug 2026 15:43:11 +0800
Subject: [PATCH] fix(tests): isolate token chunker imports (#18018)

---
 rag/flow/parser/pdf_chunk_metadata.py         | 10 ++--
 .../unit_test/rag/test_flow_chunker_import.py | 46 +++++++++++++++++++
 2 files changed, 53 insertions(+), 3 deletions(-)
 create mode 100644 test/unit_test/rag/test_flow_chunker_import.py

diff --git a/rag/flow/parser/pdf_chunk_metadata.py b/rag/flow/parser/pdf_chunk_metadata.py
index 62314f4291..60a7986ecd 100644
--- a/rag/flow/parser/pdf_chunk_metadata.py
+++ b/rag/flow/parser/pdf_chunk_metadata.py
@@ -22,11 +22,8 @@ import numpy as np
 import pdfplumber
 from PIL import Image
 
-from api.db.services.file2document_service import File2DocumentService
-from api.db.services.file_service import FileService
 from common import settings
 from common.misc_utils import get_uuid
-from deepdoc.parser.pdf_parser import LOCK_KEY_pdfplumber, RAGFlowPdfParser
 from rag.utils.base64_image import image2id
 
 PDF_PREVIEW_GAP = 6
@@ -47,6 +44,8 @@ def _extract_raw_positions(item):
 
     position_tag = item.get("position_tag")
     if isinstance(position_tag, str) and position_tag:
+        from deepdoc.parser.pdf_parser import RAGFlowPdfParser
+
         return [[pos[0][-1], *pos[1:]] for pos in RAGFlowPdfParser.extract_positions(position_tag)]
 
     position_int = item.get("position_int")
@@ -187,6 +186,9 @@ def finalize_pdf_chunk(chunk):
 
 
 def _fetch_source_blob(from_upstream, canvas):
+    from api.db.services.file2document_service import File2DocumentService
+    from api.db.services.file_service import FileService
+
     if canvas._doc_id:
         bucket, name = File2DocumentService.get_storage_address(doc_id=canvas._doc_id)
         return settings.STORAGE_IMPL.get(bucket, name)
@@ -196,6 +198,8 @@ def _fetch_source_blob(from_upstream, canvas):
 
 
 def _load_pdf_page_images(blob, zoom=PDF_PREVIEW_ZOOM):
+    from deepdoc.parser.pdf_parser import LOCK_KEY_pdfplumber
+
     with sys.modules[LOCK_KEY_pdfplumber]:
         with pdfplumber.open(io.BytesIO(blob)) as pdf:
             return [page.to_image(resolution=72 * zoom, antialias=True).annotated for page in pdf.pages]
diff --git a/test/unit_test/rag/test_flow_chunker_import.py b/test/unit_test/rag/test_flow_chunker_import.py
new file mode 100644
index 0000000000..11e56c2c63
--- /dev/null
+++ b/test/unit_test/rag/test_flow_chunker_import.py
@@ -0,0 +1,46 @@
+#
+#  Copyright 2026 The InfiniFlow Authors. All Rights Reserved.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+#
+
+import importlib
+import sys
+
+
+def test_token_chunker_imports_without_pdf_parser_symbols(pdf_parser_stub, monkeypatch):
+    monkeypatch.delattr(pdf_parser_stub, "RAGFlowPdfParser")
+    for module_name in [
+        "rag.flow.chunker",
+        "rag.flow.chunker.token_chunker",
+        "rag.flow.parser.pdf_chunk_metadata",
+    ]:
+        sys.modules.pop(module_name, None)
+
+    token_chunker = importlib.import_module("rag.flow.chunker.token_chunker")
+
+    assert callable(token_chunker._merge_text_chunks_by_token_size)
+
+    position_tag = "@@1\t10\t20\t30\t40##"
+    extracted_tags = []
+
+    class RuntimePdfParser:
+        @staticmethod
+        def extract_positions(value):
+            extracted_tags.append(value)
+            return [([0], 10.0, 20.0, 30.0, 40.0)]
+
+    monkeypatch.setattr(pdf_parser_stub, "RAGFlowPdfParser", RuntimePdfParser, raising=False)
+
+    assert token_chunker.extract_pdf_positions({"position_tag": position_tag}) == [[1, 10.0, 20.0, 30.0, 40.0]]
+    assert extracted_tags == [position_tag]