fix alpha warnings + HyperSpaceWalkerTest

h2o-algos/src/main/java/hex/glm/GLMModel.java

@@ -1031,10 +1031,10 @@ public DistributionFamily getDistributionFamily() {
     }
 
     @Override
-    public void addSearchFailureDetails(Grid.SearchFailure searchFailure, Grid grid) {
-      super.addSearchFailureDetails(searchFailure, grid);
+    public void addSearchWarnings(Grid.SearchFailure searchFailure, Grid grid) {
+      super.addSearchWarnings(searchFailure, grid);
       if (ArrayUtils.contains(grid.getHyperNames(), "alpha")) {
-        // maybe we should find a way to raise this warning at the very beginning of grid search, similar to validation ini ModelBuilder#init().
+        // maybe we should find a way to raise this warning at the very beginning of grid search, similar to validation in ModelBuilder#init().
         searchFailure.addWarning("Adding alpha array to hyperparameter runs slower with gridsearch. "+
                 "This is due to the fact that the algo has to run initialization for every alpha value. "+
                 "Setting the alpha array as a model parameter will skip the initialization and run faster overall.");

h2o-core/src/main/java/hex/Model.java

@@ -806,7 +806,7 @@ private Parameters getDefaults() {
      * @param searchFailure
      * @param grid
      */
-    public void addSearchFailureDetails(Grid.SearchFailure searchFailure, Grid grid) {}
+    public void addSearchWarnings(Grid.SearchFailure searchFailure, Grid grid) {}
   }
 
   public ModelMetrics addModelMetrics(final ModelMetrics mm) {

h2o-core/src/main/java/hex/grid/Grid.java

@@ -313,7 +313,7 @@ private void appendFailedModelParameters(final Key<Model> modelKey, final MP par
         _failures.put(searchedKey, searchFailure);
       }
       searchFailure.appendFailedModelParameters(params, rawParams, failureDetails, stackTrace);
-      if (params != null) params.addSearchFailureDetails(searchFailure, this);
+      if (params != null) params.addSearchWarnings(searchFailure, this);
   }
 
   static boolean isJobCanceled(final Throwable t) {
@@ -406,6 +406,7 @@ public SearchFailure getFailures() {
     final Collection<SearchFailure> values = _failures.values();
     // Original failures should be left intact. Also avoid mutability from outer space.
     final SearchFailure searchFailure = new SearchFailure(_params != null ? _params.getClass() : null);
+    if (_params != null) _params.addSearchWarnings(searchFailure, this);
 
     for (SearchFailure f : values) {
       searchFailure.appendFailedModelParameters(f._failed_params, f._failed_raw_params, f._failure_details,

h2o-core/src/test/java/hex/HyperSpaceWalkerTest.java

@@ -7,6 +7,7 @@
 import org.junit.Test;
 import water.TestUtil;
 import water.test.dummy.DummyModelParameters;
+import water.util.ReflectionUtils;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -16,6 +17,17 @@ public class HyperSpaceWalkerTest extends TestUtil {
     @BeforeClass public static void stall() { stall_till_cloudsize(1); }
 
     static public class DummyXGBoostModelParameters extends DummyModelParameters {
+
+        private static final DummyXGBoostModelParameters DEFAULTS;
+
+        static {
+          try {
+            DEFAULTS = DummyXGBoostModelParameters.class.newInstance();
+          } catch (Exception e) {
+            throw new RuntimeException(e);
+          }
+        }
+
         public int _max_depth;
         public double _min_rows;
         public double _sample_rate;
@@ -26,6 +38,12 @@ static public class DummyXGBoostModelParameters extends DummyModelParameters {
         public float _reg_alpha;
         public float _scale_pos_weight;
         public float _max_delta_step;
+
+      @Override
+      public Object getParameterDefaultValue(String name) {
+        // tricking the default logic here as this parameters class is not properly registered, so we can't obtain the defaults the usual way.
+        return ReflectionUtils.getFieldValue(DEFAULTS, name);
+      }
     }
 
 

h2o-py/tests/testdir_algos/glm/pyunit_PUBDEV_8150_warning_alpha_grid.py

@@ -1,16 +1,13 @@
 from builtins import range
+import contextlib
+from io import StringIO
 import sys
 sys.path.insert(1,"../../../")
 import h2o
 from tests import pyunit_utils
 from h2o.estimators.glm import H2OGeneralizedLinearEstimator
 from h2o.grid.grid_search import H2OGridSearch
 
-try:    # redirect python output
-    from StringIO import StringIO  # for python 3
-except ImportError:
-    from io import StringIO  # for python 2
-
 # This test is used to make sure when a user tries to set alpha in the hyper-parameter of gridsearch, a warning
 # should appear to tell the user to set the alpha array as an parameter in the algorithm.
 def grid_alpha_search():
@@ -25,23 +22,17 @@ def grid_alpha_search():
     hyper_parameters = {'alpha': [0, 0.5]}    # set hyper_parameters for grid search
 
     print("Create models with lambda_search")
-    buffer = StringIO() # redirect output
-    sys.stderr=buffer
-    model_h2o_grid_search = H2OGridSearch(H2OGeneralizedLinearEstimator(family="tweedie", Lambda=0.5),
-                                          hyper_parameters)
-    model_h2o_grid_search.train(x=x, y=y, training_frame=hdf)
-    sys.stderr=sys.__stderr__   # redirect printout back to normal path
+    err = StringIO() 
+    with contextlib.redirect_stderr(err):
+        model_h2o_grid_search = H2OGridSearch(H2OGeneralizedLinearEstimator(family="tweedie", Lambda=0.5),
+                                              hyper_parameters)
+        model_h2o_grid_search.train(x=x, y=y, training_frame=hdf)
 
     # check and make sure we get the correct warning message
     warn_phrase = "Adding alpha array to hyperparameter runs slower with gridsearch."
-    try:        # for python 2.7
-        assert len(buffer.buflist)==warnNumber
-        print(buffer.buflist[0])
-        assert warn_phrase in buffer.buflist[0]
-    except:     # for python 3.
-        warns = buffer.getvalue()
-        print("*** captured warning message: {0}".format(warns))
-        assert warn_phrase in warns
+    warns = err.getvalue()
+    print("*** captured warning message: {0}".format(warns))
+    assert warn_phrase in warns
 
 if __name__ == "__main__":
     pyunit_utils.standalone_test(grid_alpha_search)