Restore compatibility with Scrapy < 2.11 (#74)

* Restore compatibility with Scrapy < 2.11

* Silence the warning when passing binary=False to PythonItemExporter

* Revert "Silence the warning when passing binary=False to PythonItemExporter"

This reverts commit ffe408f.

sh_scrapy/extension.py

@@ -4,6 +4,7 @@
 
 import scrapy
 from scrapy import signals
+from scrapy import version_info as SCRAPY_VERSION_INFO
 from scrapy.exceptions import ScrapyDeprecationWarning
 from scrapy.exporters import PythonItemExporter
 from scrapy.http import Request
@@ -41,7 +42,10 @@ def __init__(self, crawler):
         self.crawler = crawler
         self.logger = logging.getLogger(__name__)
         self._write_item = self.pipe_writer.write_item
-        self.exporter = PythonItemExporter()
+        kwargs = {}
+        if SCRAPY_VERSION_INFO < (2, 11):
+            kwargs["binary"] = False
+        self.exporter = PythonItemExporter(**kwargs)
 
     @classmethod
     def from_crawler(cls, crawler):

tests/test_extension.py

@@ -26,6 +26,7 @@ def test_hs_ext_init(hs_ext):
     assert hs_ext.crawler
     assert hs_ext._write_item == hs_ext.pipe_writer.write_item
     assert isinstance(hs_ext.exporter, PythonItemExporter)
+    assert hs_ext.exporter.export_item({"a": "b"}) == {"a": "b"}
 
 
 @pytest.mark.skipif(sys.version_info < (3, 7), reason="requires python3.7")