maxModels instead of time for AutoML unit test (dotnet#5471)

Uses the internal `maxModels` parameter instead of `MaxExperimentTimeInSeconds` for the exit criteria of AutoML. This is to increase the test stability in case the test is run on a slower machine.

Author: justinormont

test/Microsoft.ML.AutoML.Tests/AutoFitTests.cs

@@ -121,11 +121,11 @@ public void AutoFitRegressionTest(string culture)
  // the sweeper encounters problems when parsing some strings.
  // So testing in another culture is necessary.
  // Furthermore, these issues might only occur after ~70
- // iterations, so more experiment time is needed for this to
- // occur.
- uint experimentTime = (uint) (culture == "en-US" ? 0 : 180);
+ // iterations, so setting the internal maxModels parameter.
+ int maxModels = culture == "en-US" ? 1 : 75;
+
+ var experimentSettings = new RegressionExperimentSettings { MaxModels = maxModels };
 
- var experimentSettings = new RegressionExperimentSettings { MaxExperimentTimeInSeconds = experimentTime};
  if (!Environment.Is64BitProcess)
  {
  // LightGBM isn't available on x86 machines
@@ -144,27 +144,10 @@ public void AutoFitRegressionTest(string culture)
  .Execute(trainData, validationData,
  new ColumnInformation() { LabelColumnName = DatasetUtil.MlNetGeneratedRegressionLabel });
 
- Assert.True(result.RunDetails.Max(i => i?.ValidationMetrics?.RSquared) > 0.9);
+ Assert.True(result.RunDetails.Max(i => i?.ValidationMetrics?.RSquared) > 0.99);
 
- // Ensure experimentTime allows enough iterations to fully test the internationalization code
- // If the below assertion fails, increase the experiment time so the number of iterations is met
- Assert.True(culture == "en-US" || result.RunDetails.Count() >= 75, $"RunDetails.Count() = {result.RunDetails.Count()}, below 75");
- }
- catch (AggregateException ae)
-{
- // During CI unit testing, the host machines can run slower than normal, which
- // can increase the run time of unit tests and throw OperationCanceledExceptions
- // from multiple threads in the form of a single AggregateException.
- foreach (var ex in ae.Flatten().InnerExceptions)
- {
- var ignoredExceptions = new List<Exception>();
- if (ex is OperationCanceledException)
- continue;
- else
- ignoredExceptions.Add(ex);
- if (ignoredExceptions.Count > 0)
- throw new AggregateException(ignoredExceptions);
- }
+ // Test the internal maxModels parameter
+ Assert.True(culture == "en-US" || result.RunDetails.Count() == 75, $"RunDetails.Count() = {result.RunDetails.Count()}, is not 75");
  }
  finally
  {