Add extraction test for empty implicit collection

        collection_step_state = loads(collection_step["tool_state"])

        assert collection_step_state["collection_type"] == "paired"

    def test_empty_collection_map_over_extract_workflow(self):

        with self.dataset_populator.test_history() as history_id:

            self._run_workflow(

                """class: GalaxyWorkflow

inputs:

  input: collection

  filter_file: data

steps:

  filter_collection:

    tool_id: __FILTER_FROM_FILE__

    in:

       input: input

       how|filter_source: filter_file

    state:

       how:

         how_filter: remove_if_present

  concat:

    tool_id: cat1

    in:

      input1: filter_collection/output_filtered

test_data:

  input:

    collection_type: list

    elements:

      - identifier: i1

        content: "0"

  filter_file: i1""",

                history_id,

                wait=True,

            )

            response = self._post(

                "workflows", data={"from_history_id": history_id, "workflow_name": "extract with empty collection test"}

            )

            assert response.status_code == 200

            workflow_id = response.json()["id"]

            workflow = self.workflow_populator.download_workflow(workflow_id)

            assert workflow

            # TODO: after adding request models we should be able to recover implicit collection job requests.

            # assert len(workflow["steps"]) == 4

    @skip_without_tool("cat_collection")

    def test_subcollection_mapping(self, history_id):

        jobs_summary = self._run_workflow(