Added a test case for the saxutils.prepare_input_source setSystemId bug.

Lib/test/output/test_sax

@@ -8,6 +8,7 @@ Passed test_expat_attrs_empty
 Passed test_expat_attrs_wattr
 Passed test_expat_dtdhandler
 Passed test_expat_entityresolver
+Passed test_expat_file
 Passed test_expat_incomplete
 Passed test_expat_incremental
 Passed test_expat_incremental_reset
@@ -30,4 +31,4 @@ Passed test_xmlgen_content_escape
 Passed test_xmlgen_ignorable
 Passed test_xmlgen_ns
 Passed test_xmlgen_pi
-31 tests, 0 failures
+32 tests, 0 failures

Lib/test/test_sax.py

@@ -185,6 +185,18 @@ def test_filter_basic():
 #
 # ===========================================================================
 
+# ===== XMLReader support
+
+def test_expat_file():
+    parser = create_parser()
+    result = StringIO()
+    xmlgen = XMLGenerator(result)
+
+    parser.setContentHandler(xmlgen)
+    parser.parse(open(findfile("test.xml")))
+
+    return result.getvalue() == xml_test_out
+
 # ===== DTDHandler support
 
 class TestDTDHandler: