There seems to be an inconsistency regarding what the dataset key should contain for a CORDEX project dataset.

• For download to work, dataset value must contain only the name of the rcm (e.g. RCA4), which is mapped to rcm_name in the facet used for download
• In order for the correct dataset fixes to be applied (i.e. for the correct file in _fixes/cordex to be imported), dataset must contain the institute id and rcm name concatenated with a dash (e.g. SMHI-RCA4).

Compare the dataset value in the tests for the two cases, which shows the difference:

Download test (look for the CORDEX test):
tests/integration/esgf/test_search_download.py

and any of the CORDEX _fixes tests, e.g.:
tests/integration/cmor/_fixes/cordex/test_ichec_ec_earth.py

Running the following recipe completes as a successful run, but the program never enters TimeLongName.fix_metadata(...) in esmvalcore/cmor/_fixes/cordex/cordex_fixes.py which should be used by this dataset:

documentation:
  description: CORDEX download example
  title: CORDEX download example
  authors:
    - righi_mattia

datasets:
- {dataset: RCA4, project: CORDEX, domain: EUR-11,
     exp: historical, ensemble: r12i1p1,
     mip: mon, institute: SMHI, rcm_version: v1,
     driver: ICHEC-EC-EARTH, version: v20131026}

diagnostics:
  map:
    description: EUR-11 map of temperature in January 2000.
    variables:
      tas:
        timerange: 2000/P1M
    scripts:
      script1:
        script: examples/diagnostic.py
        quickplot:
          plot_type: pcolormesh
          cmap: Reds