fix(chart): prevent chart list from failing when a datasource lacks explore_url (#38721)

tests/unit_tests/models/slice_test.py

@@ -85,3 +85,41 @@ class TestSlice:
         """Test id_or_uuid_filter returns correct BinaryExpression."""
         result = id_or_uuid_filter(input_value)
         assert result is not None
+
+    def test_datasource_url_returns_none_when_datasource_lacks_explore_url(self):
+        """datasource_url() must not raise when the datasource has no explore_url.
+
+        Charts whose datasource resolves to a Query (or any other type without
+        explore_url) used to raise AttributeError, which caused the entire chart
+        list API response to fail instead of just skipping that one chart.
+        """
+        slc = Slice()
+        slc.id = 1
+
+        # Simulate a datasource object that does NOT have explore_url (e.g. Query)
+        mock_datasource = MagicMock(spec=[])  # spec=[] means no attributes at all
+        slc.table = mock_datasource
+
+        result = slc.datasource_url()
+        assert result is None
+
+    def test_datasource_url_returns_explore_url_when_present(self):
+        """datasource_url() returns the datasource explore_url when it exists."""
+        slc = Slice()
+        slc.id = 1
+
+        mock_table = MagicMock()
+        mock_table.explore_url = "/explore/?datasource_type=table&datasource_id=1"
+        slc.table = mock_table
+
+        result = slc.datasource_url()
+        assert result == "/explore/?datasource_type=table&datasource_id=1"
+
+    def test_datasource_url_returns_none_when_no_datasource(self):
+        """datasource_url() returns None when there is no datasource."""
+        slc = Slice()
+        slc.id = 1
+        slc.table = None
+
+        result = slc.datasource_url()
+        assert result is None