Allow deprecated regridding scheme linear_extrapolate in recipe che…

…cks (#2324)

esmvalcore/_recipe/check.py

@@ -506,6 +506,13 @@ def regridding_schemes(settings: dict):
  # Check built-in regridding schemes (given as str)
  if isinstance(scheme, str):
  scheme = settings['regrid']['scheme']
+
+ # Also allow deprecated 'linear_extrapolate' scheme (the corresponding
+ # deprecation warning will be raised in the regrid() preprocessor)
+ # TODO: Remove in v2.13.0
+ if scheme == 'linear_extrapolate':
+ return
+
  allowed_regridding_schemes = list(
  set(
  list(HORIZONTAL_SCHEMES_IRREGULAR) +

tests/integration/recipe/test_recipe.py

@@ -2884,6 +2884,7 @@ def test_invalid_builtin_regridding_scheme(
  test:
  regrid:
  scheme: INVALID
+ target_grid: 2x2
  diagnostics:
  diagnostic_name:
  variables:
@@ -2914,6 +2915,7 @@ def test_generic_regridding_scheme_no_ref(
  regrid:
  scheme:
  no_reference: given
+ target_grid: 2x2
  diagnostics:
  diagnostic_name:
  variables:
@@ -2945,6 +2947,7 @@ def test_invalid_generic_regridding_scheme(
  regrid:
  scheme:
  reference: invalid.module:and.function
+ target_grid: 2x2
  diagnostics:
  diagnostic_name:
  variables:
@@ -2966,3 +2969,25 @@ def test_invalid_generic_regridding_scheme(
  get_recipe(tmp_path, content, session)
  assert str(rec_err_exp.value) == INITIALIZATION_ERROR_MSG
  assert msg in str(rec_err_exp.value.failed_tasks[0].message)
+
+
+def test_deprecated_regridding_scheme(tmp_path, patched_datafinder, session):
+ content = dedent("""
+ preprocessors:
+ test:
+ regrid:
+ scheme: linear_extrapolate
+ target_grid: 2x2
+ diagnostics:
+ diagnostic_name:
+ variables:
+ tas:
+ mip: Amon
+ preprocessor: test
+ timerange: '2000/2010'
+ additional_datasets:
+ - {project: CMIP5, dataset: CanESM2, exp: amip,
+ ensemble: r1i1p1}
+ scripts: null
+ """)
+ get_recipe(tmp_path, content, session)