Add filter on doc and example packages when option "all_extra" is enabled.

Add test.

tests/test_doc_archives.py

@@ -0,0 +1,35 @@
+import os
+
+import pytest
+
+from aqt.archives import QtArchives
+
+
+@pytest.mark.parametrize("os_name,version,target,datafile", [
+    ('windows', '5.15.2', 'doc', 'windows-5152-src-doc-example-update.xml')
+])
+def test_parse_update_xml(monkeypatch, os_name, version, target, datafile):
+
+    def _mock(self, url):
+        with open(os.path.join(os.path.dirname(__file__), 'data', datafile), 'r') as f:
+            self.update_xml_text = f.read()
+
+    monkeypatch.setattr(QtArchives, "_download_update_xml", _mock)
+
+    qt_archives = QtArchives(os_name, 'desktop', version, target)
+    assert qt_archives.archives is not None
+
+    # Get packages with all extra modules
+    qt_archives_all_modules = QtArchives(os_name, 'desktop', version, target, None, ['all'], None, None, True)
+    assert qt_archives_all_modules.archives is not None
+
+    # Extract all urls
+    url_list = [item.url for item in qt_archives.archives]
+    url_all_modules_list = [item.url for item in qt_archives_all_modules.archives]
+
+    # Check the difference list contains only extra modules urls for target specified
+    list_diff = [item for item in url_all_modules_list if item not in url_list]
+    unwanted_targets = [item for item in list_diff if target not in item]
+
+    # Assert if list_diff contains urls without target specified
+    assert unwanted_targets == []