Retain updated Estimator in Corrector-generated MetaResults (#633)

* Retain updated Estimator in corrected MetaResult.

* Update test.

* Update the test again.

* Fix the problem.

nimare/correct.py

@@ -115,12 +115,14 @@ def transform(self, result):
         result : :obj:`~nimare.results.MetaResult`
             MetaResult with new corrected maps added.
         """
-        est = result.estimator
         correction_method = f"correct_{self._correction_method}_{self.method}"
 
         # Make sure we return a copy of the MetaResult
         result = result.copy()
 
+        # Also operate on a copy of the estimator
+        est = result.estimator
+
         # If a correction method with the same name exists in the current
         # MetaEstimator, use it. Otherwise fall back on _transform.
         if correction_method is not None and hasattr(est, correction_method):
@@ -136,6 +138,10 @@ def transform(self, result):
         # Update corrected map names and add them to maps dict
         corr_maps = {(k + self._name_suffix): v for k, v in corr_maps.items()}
         result.maps.update(corr_maps)
+
+        # Update the estimator as well, in order to retain updated null distributions
+        result.estimator = est
+
         return result
 
     @abstractmethod

nimare/tests/test_meta_ale.py

@@ -216,6 +216,26 @@ def test_ALE_montecarlo_null_unit(testdata_cbma, tmp_path_factory):
         np.ndarray,
     )
 
+    # Check that the updated null distribution is in the corrected MetaResult's Estimator.
+    assert (
+        "values_desc-mass_level-cluster_corr-fwe_method-montecarlo"
+        in cres.estimator.null_distributions_.keys()
+    )
+    # The updated null distribution should *not* be in the original Estimator, nor in the
+    # uncorrected MetaResult's Estimator.
+    assert (
+        "values_desc-mass_level-cluster_corr-fwe_method-montecarlo"
+        not in meta.null_distributions_.keys()
+    )
+    assert (
+        "values_desc-mass_level-cluster_corr-fwe_method-montecarlo"
+        not in res.estimator.null_distributions_.keys()
+    )
+    assert (
+        "values_desc-mass_level-cluster_corr-fwe_method-montecarlo"
+        not in meta.results.estimator.null_distributions_.keys()
+    )
+
     # Bonferroni FWE
     corr = FWECorrector(method="bonferroni")
     cres = corr.transform(res)