Use HideEnumValueAttribute for both manifest and C# API generation.

Author: Tom Finley

src/Microsoft.ML/CSharpApi.cs

@@ -11058,14 +11058,10 @@ namespace Transforms
     {
         public enum NAHandleTransformReplacementKind
         {
-            Default = 0,
-            Def = 0,
             DefaultValue = 0,
             Mean = 1,
             Minimum = 2,
-            Min = 2,
-            Maximum = 3,
-            Max = 3
+            Maximum = 3
         }
 
 
@@ -11153,7 +11149,7 @@ public void AddColumn(string outputColumn, string inputColumn)
             /// <summary>
             /// The replacement method to utilize
             /// </summary>
-            public NAHandleTransformReplacementKind ReplaceWith { get; set; } = NAHandleTransformReplacementKind.Def;
+            public NAHandleTransformReplacementKind ReplaceWith { get; set; } = NAHandleTransformReplacementKind.DefaultValue;
 
             /// <summary>
             /// Whether to impute values by slot
@@ -11527,17 +11523,10 @@ namespace Transforms
     {
         public enum NAReplaceTransformReplacementKind
         {
-            Default = 0,
             DefaultValue = 0,
-            Def = 0,
             Mean = 1,
-            Min = 2,
             Minimum = 2,
-            Max = 3,
-            Maximum = 3,
-            SpecifiedValue = 4,
-            Val = 4,
-            Value = 4
+            Maximum = 3
         }
 
 
@@ -11625,7 +11614,7 @@ public void AddColumn(string outputColumn, string inputColumn)
             /// <summary>
             /// The replacement method to utilize
             /// </summary>
-            public NAReplaceTransformReplacementKind ReplacementKind { get; set; } = NAReplaceTransformReplacementKind.Def;
+            public NAReplaceTransformReplacementKind ReplacementKind { get; set; } = NAReplaceTransformReplacementKind.DefaultValue;
 
             /// <summary>
             /// Whether to impute values by slot

src/Microsoft.ML/Runtime/EntryPoints/JsonUtils/JsonManifestUtils.cs

@@ -344,7 +344,7 @@ private static JToken BuildTypeToken(IExceptionContext ectx, FieldInfo fieldInfo
                 case TlcModule.DataKind.Enum:
                     jo = new JObject();
                     jo[FieldNames.Kind] = typeEnum.ToString();
-                    var values = Enum.GetNames(type);
+                    var values = Enum.GetNames(type).Where(n => type.GetField(n).GetCustomAttribute<HideEnumValueAttribute>() == null);
                     jo[FieldNames.Values] = new JArray(values);
                     return jo;
                 case TlcModule.DataKind.Array:

src/Microsoft.ML/Runtime/Internal/Tools/CSharpApiGenerator.cs

@@ -6,6 +6,7 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Reflection;
 using Microsoft.ML.Runtime;
 using Microsoft.ML.Runtime.CommandLine;
 using Microsoft.ML.Runtime.Data;
@@ -156,6 +157,8 @@ private void GenerateEnums(IndentingTextWriter writer, Type inputType, string cu
                 for (int i = 0; i < names.Length; i++)
                 {
                     var name = names[i];
+                    if (type.GetField(name).GetCustomAttribute<HideEnumValueAttribute>() != null)
+                        continue;
                     var value = values.GetValue(i);
                     writer.WriteLine(prefix);
                     if (enumType == typeof(int))

src/Microsoft.ML/Runtime/Internal/Tools/CSharpGeneratorUtils.cs

@@ -6,6 +6,7 @@
 using System.CodeDom;
 using System.Collections.Generic;
 using System.Linq;
+using System.Reflection;
 using Microsoft.CSharp;
 using Microsoft.ML.Runtime.CommandLine;
 using Microsoft.ML.Runtime.EntryPoints;
@@ -279,10 +280,22 @@ public static string GetValue(ModuleCatalog catalog, Type fieldType, object fiel
                 case TlcModule.DataKind.Bool:
                     return (bool)fieldValue ? "true" : "false";
                 case TlcModule.DataKind.Enum:
+                    string enumAsString = fieldValue.ToString();
+                    if (fieldType.GetField(enumAsString).GetCustomAttribute<HideEnumValueAttribute>() != null)
+                    {
+                        // The default value for the enum has the hiding attribute on it. We will search for
+                        // alternate names. Regrettably I see no way beyond a manual scan.
+
+                        string unhiddenName = Enum.GetNames(fieldType).Zip(Enum.GetValues(fieldType).Cast<object>(), (name, val) => (name, val))
+                            .Where(pair => pair.val.Equals(fieldValue))
+                            .Where(pair => fieldType.GetField(pair.name).GetCustomAttribute<HideEnumValueAttribute>() == null)
+                            .Select(pair => pair.name).FirstOrDefault();
+                        enumAsString = unhiddenName ?? throw Contracts.Except($"Could not find unhidden alternative for '{fieldValue}' in type '{fieldType}'");
+                    }
                     if (generatedClasses.IsGenerated(fieldType.FullName))
-                        return generatedClasses.GetApiName(fieldType, rootNameSpace) + "." + fieldValue;
+                        return generatedClasses.GetApiName(fieldType, rootNameSpace) + "." + enumAsString;
                     else
-                        return generatedClasses.GetApiName(fieldType, "Runtime") + "." + fieldValue;
+                        return generatedClasses.GetApiName(fieldType, "Runtime") + "." + enumAsString;
                 case TlcModule.DataKind.Char:
                     return $"'{GetCharAsString((char)fieldValue)}'";
                 case TlcModule.DataKind.Component:

test/BaselineOutput/Common/EntryPoints/core_manifest.json

@@ -15390,14 +15390,10 @@
                   "Type": {
                     "Kind": "Enum",
                     "Values": [
-                      "Default",
-                      "Def",
                       "DefaultValue",
                       "Mean",
                       "Minimum",
-                      "Min",
-                      "Maximum",
-                      "Max"
+                      "Maximum"
                     ]
                   },
                   "Desc": "The replacement method to utilize",
@@ -15478,14 +15474,10 @@
           "Type": {
             "Kind": "Enum",
             "Values": [
-              "Default",
-              "Def",
               "DefaultValue",
               "Mean",
               "Minimum",
-              "Min",
-              "Maximum",
-              "Max"
+              "Maximum"
             ]
           },
           "Desc": "The replacement method to utilize",
@@ -15780,17 +15772,10 @@
                   "Type": {
                     "Kind": "Enum",
                     "Values": [
-                      "Default",
                       "DefaultValue",
-                      "Def",
                       "Mean",
-                      "Min",
                       "Minimum",
-                      "Max",
-                      "Maximum",
-                      "SpecifiedValue",
-                      "Val",
-                      "Value"
+                      "Maximum"
                     ]
                   },
                   "Desc": "The replacement method to utilize",
@@ -15856,17 +15841,10 @@
           "Type": {
             "Kind": "Enum",
             "Values": [
-              "Default",
               "DefaultValue",
-              "Def",
               "Mean",
-              "Min",
               "Minimum",
-              "Max",
-              "Maximum",
-              "SpecifiedValue",
-              "Val",
-              "Value"
+              "Maximum"
             ]
           },
           "Desc": "The replacement method to utilize",