Moved ini utils to separate file.

Author: Shahab Moradi

src/Microsoft.ML.FastTree/FastTree.cs

@@ -2985,7 +2985,7 @@ void ICanSaveInTextFormat.SaveAsText(TextWriter writer, RoleMappedSchema schema)
         void ICanSaveInIniFormat.SaveAsIni(TextWriter writer, RoleMappedSchema schema, ICalibrator calibrator)
         {
             Host.CheckValue(writer, nameof(writer));
-            var ensembleIni = FastTreeIniFormatUtils.TreeEnsembleToIni(Host, TrainedEnsemble, schema, calibrator,
+            var ensembleIni = FastTreeIniFileUtils.TreeEnsembleToIni(Host, TrainedEnsemble, schema, calibrator,
                 InnerArgs, appendFeatureGain: true, includeZeroGainFeatures: false);
             writer.WriteLine(ensembleIni);
         }
@@ -3373,46 +3373,4 @@ public TreeNode(Dictionary<string, object> keyValues)
             public Dictionary<string, object> KeyValues { get; }
         }
     }
-    internal static class FastTreeIniFormatUtils
-    {
-        public static string TreeEnsembleToIni(
-            IHost host, TreeEnsemble ensemble, RoleMappedSchema schema, ICalibrator calibrator,
-            string trainingParams, bool appendFeatureGain, bool includeZeroGainFeatures)
-        {
-            host.CheckValue(ensemble, nameof(ensemble));
-            host.CheckValue(schema, nameof(schema));
-
-            string ensembleIni = ensemble.ToTreeEnsembleIni(new FeaturesToContentMap(schema),
-                trainingParams, appendFeatureGain, includeZeroGainFeatures);
-            ensembleIni = AddCalibrationToIni(host, ensembleIni, calibrator);
-            return ensembleIni;
-        }
-
-        /// <summary>
-        /// Get the calibration summary in INI format
-        /// </summary>
-        private static string AddCalibrationToIni(IHost host, string ini, ICalibrator calibrator)
-        {
-            host.AssertValue(ini);
-            host.AssertValueOrNull(calibrator);
-
-            if (calibrator == null)
-                return ini;
-
-            if (calibrator is PlattCalibrator)
-            {
-                string calibratorEvaluatorIni = IniFileUtils.GetCalibratorEvaluatorIni(ini, calibrator as PlattCalibrator);
-                return IniFileUtils.AddEvaluator(ini, calibratorEvaluatorIni);
-            }
-            else
-            {
-                StringBuilder newSection = new StringBuilder();
-                newSection.AppendLine();
-                newSection.AppendLine();
-                newSection.AppendLine("[TLCCalibration]");
-                newSection.AppendLine("Type=" + calibrator.GetType().Name);
-                return ini + newSection;
-            }
-        }
-    }
 }

src/Microsoft.ML.FastTree/GamTrainer.cs

@@ -1060,7 +1060,7 @@ void ICanSaveInIniFormat.SaveAsIni(TextWriter writer, RoleMappedSchema schema, I
                 leafValues: new[] { Intercept, Intercept });
             ensemble.AddTree(interceptTree);
 
-            var ini = FastTreeIniFormatUtils.TreeEnsembleToIni(
+            var ini = FastTreeIniFileUtils.TreeEnsembleToIni(
                 Host, ensemble, schema, calibrator, string.Empty, false, false);
 
             // Remove the SplitGain values which are all 0.

src/Microsoft.ML.FastTree/Utils/FastTreeIniFileUtils.cs

@@ -0,0 +1,53 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using Microsoft.ML.Calibrator;
+using Microsoft.ML.Data;
+using Microsoft.ML.Internal.Calibration;
+using Microsoft.ML.Internal.Utilities;
+
+namespace Microsoft.ML.Trainers.FastTree.Internal
+{
+    internal static class FastTreeIniFileUtils
+    {
+        public static string TreeEnsembleToIni(
+            IHost host, TreeEnsemble ensemble, RoleMappedSchema schema, ICalibrator calibrator,
+            string trainingParams, bool appendFeatureGain, bool includeZeroGainFeatures)
+        {
+            host.CheckValue(ensemble, nameof(ensemble));
+            host.CheckValue(schema, nameof(schema));
+
+            string ensembleIni = ensemble.ToTreeEnsembleIni(new FeaturesToContentMap(schema),
+                trainingParams, appendFeatureGain, includeZeroGainFeatures);
+            ensembleIni = AddCalibrationToIni(host, ensembleIni, calibrator);
+            return ensembleIni;
+        }
+
+        /// <summary>
+        /// Get the calibration summary in INI format
+        /// </summary>
+        private static string AddCalibrationToIni(IHost host, string ini, ICalibrator calibrator)
+        {
+            host.AssertValue(ini);
+            host.AssertValueOrNull(calibrator);
+
+            if (calibrator == null)
+                return ini;
+
+            if (calibrator is PlattCalibrator)
+            {
+                string calibratorEvaluatorIni = IniFileUtils.GetCalibratorEvaluatorIni(ini, calibrator as PlattCalibrator);
+                return IniFileUtils.AddEvaluator(ini, calibratorEvaluatorIni);
+            }
+            else
+            {
+                StringBuilder newSection = new StringBuilder();
+                newSection.AppendLine();
+                newSection.AppendLine();
+                newSection.AppendLine("[TLCCalibration]");
+                newSection.AppendLine("Type=" + calibrator.GetType().Name);
+                return ini + newSection;
+            }
+        }
+    }
+}