Major reduction in public surface area of WixToolset.Core

38 files changed, 110 insertions, 220 deletions

diff --git a/src/WixToolset.Core/Bind/FileFacade.cs b/src/WixToolset.Core/Bind/FileFacade.cs
index ebca9cff..825c2c7a 100644
--- a/src/WixToolset.Core/Bind/FileFacade.cs
+++ b/src/WixToolset.Core/Bind/FileFacade.cs
@@ -21,13 +21,13 @@ namespace WixToolset.Core.Bind
             this.WixFile = wixFile;
         }
 
-        public bool FromModule { get; private set; }
+        public bool FromModule { get; }
 
-        public FileTuple File { get; private set; }
+        public FileTuple File { get; }
 
-        public WixFileTuple WixFile { get; private set; }
+        public WixFileTuple WixFile { get; }
 
-        public WixDeltaPatchFileTuple DeltaPatchFile { get; private set; }
+        public WixDeltaPatchFileTuple DeltaPatchFile { get; }
 
         /// <summary>
         /// Gets the set of MsiAssemblyName rows created for this file.
diff --git a/src/WixToolset.Core/BindContext.cs b/src/WixToolset.Core/BindContext.cs
index 12719f51..413be301 100644
--- a/src/WixToolset.Core/BindContext.cs
+++ b/src/WixToolset.Core/BindContext.cs
@@ -8,7 +8,7 @@ namespace WixToolset.Core
     using WixToolset.Extensibility;
     using WixToolset.Extensibility.Data;
 
-    public class BindContext : IBindContext
+    internal class BindContext : IBindContext
     {
         internal BindContext(IServiceProvider serviceProvider)
         {
diff --git a/src/WixToolset.Core/Binder.cs b/src/WixToolset.Core/Binder.cs
index 2a40ce71..bbc4173b 100644
--- a/src/WixToolset.Core/Binder.cs
+++ b/src/WixToolset.Core/Binder.cs
@@ -16,9 +16,9 @@ namespace WixToolset.Core
     /// <summary>
     /// Binder of the WiX toolset.
     /// </summary>
-    public sealed class Binder
+    internal class Binder
     {
-        public Binder(IServiceProvider serviceProvider)
+        internal Binder(IServiceProvider serviceProvider)
         {
             this.ServiceProvider = serviceProvider;
         }
diff --git a/src/WixToolset.Core/CommandLine/BuildCommand.cs b/src/WixToolset.Core/CommandLine/BuildCommand.cs
index 822c4a9a..5c089b5f 100644
--- a/src/WixToolset.Core/CommandLine/BuildCommand.cs
+++ b/src/WixToolset.Core/CommandLine/BuildCommand.cs
@@ -317,6 +317,8 @@ namespace WixToolset.Core.CommandLine
 
         private IEnumerable<Localization> LoadLocalizationFiles()
         {
+            var localizer = new Localizer(this.ServiceProvider);
+
             foreach (var loc in this.LocFiles)
             {
                 var preprocessor = new Preprocessor(this.ServiceProvider);
@@ -331,8 +333,7 @@ namespace WixToolset.Core.CommandLine
                     continue;
                 }
 
-                var localization = Localizer.ParseLocalizationFile(this.Messaging, document);
-
+                var localization = localizer.ParseLocalizationFile(document);
                 yield return localization;
             }
         }
diff --git a/src/WixToolset.Core/CommandLine/CommandLineResponseFile.cs b/src/WixToolset.Core/CommandLine/CommandLineResponseFile.cs
deleted file mode 100644
index 6922b246..00000000
--- a/src/WixToolset.Core/CommandLine/CommandLineResponseFile.cs
+++ /dev/null
@@ -1,132 +0,0 @@
-// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
-
-namespace WixToolset.Core.CommandLine
-{
-    using System;
-    using System.Collections;
-    using System.Collections.Generic;
-    using System.IO;
-    using System.Text;
-    using System.Text.RegularExpressions;
-
-    /// <summary>
-    /// Common utilities for Wix command-line processing.
-    /// </summary>
-    public static class CommandLineResponseFile
-    {
-        /// <summary>
-        /// Parses a response file.
-        /// </summary>
-        /// <param name="responseFile">The file to parse.</param>
-        /// <returns>The array of arguments.</returns>
-        public static string[] Parse(string responseFile)
-        {
-            string arguments;
-
-            using (StreamReader reader = new StreamReader(responseFile))
-            {
-                arguments = reader.ReadToEnd();
-            }
-
-            return CommandLineResponseFile.ParseArgumentsToArray(arguments);
-        }
-
-        /// <summary>
-        /// Parses an argument string into an argument array based on whitespace and quoting.
-        /// </summary>
-        /// <param name="arguments">Argument string.</param>
-        /// <returns>Argument array.</returns>
-        public static string[] ParseArgumentsToArray(string arguments)
-        {
-            // Scan and parse the arguments string, dividing up the arguments based on whitespace.
-            // Unescaped quotes cause whitespace to be ignored, while the quotes themselves are removed.
-            // Quotes may begin and end inside arguments; they don't necessarily just surround whole arguments.
-            // Escaped quotes and escaped backslashes also need to be unescaped by this process.
-
-            // Collects the final list of arguments to be returned.
-            List<string> argsList = new List<string>();
-
-            // True if we are inside an unescaped quote, meaning whitespace should be ignored.
-            bool insideQuote = false;
-
-            // Index of the start of the current argument substring; either the start of the argument
-            // or the start of a quoted or unquoted sequence within it.
-            int partStart = 0;
-
-            // The current argument string being built; when completed it will be added to the list.
-            StringBuilder arg = new StringBuilder();
-
-            for (int i = 0; i <= arguments.Length; i++)
-            {
-                if (i == arguments.Length || (Char.IsWhiteSpace(arguments[i]) && !insideQuote))
-                {
-                    // Reached a whitespace separator or the end of the string.
-
-                    // Finish building the current argument.
-                    arg.Append(arguments.Substring(partStart, i - partStart));
-
-                    // Skip over the whitespace character.
-                    partStart = i + 1;
-
-                    // Add the argument to the list if it's not empty.
-                    if (arg.Length > 0)
-                    {
-                        argsList.Add(CommandLineResponseFile.ExpandEnvVars(arg.ToString()));
-                        arg.Length = 0;
-                    }
-                }
-                else if (i > partStart && arguments[i - 1] == '\\')
-                {
-                    // Check the character following an unprocessed backslash.
-                    // Unescape quotes, and backslashes followed by a quote.
-                    if (arguments[i] == '"' || (arguments[i] == '\\' && arguments.Length > i + 1 && arguments[i + 1] == '"'))
-                    {
-                        // Unescape the quote or backslash by skipping the preceeding backslash.
-                        arg.Append(arguments.Substring(partStart, i - 1 - partStart));
-                        arg.Append(arguments[i]);
-                        partStart = i + 1;
-                    }
-                }
-                else if (arguments[i] == '"')
-                {
-                    // Add the quoted or unquoted section to the argument string.
-                    arg.Append(arguments.Substring(partStart, i - partStart));
-
-                    // And skip over the quote character.
-                    partStart = i + 1;
-
-                    insideQuote = !insideQuote;
-                }
-            }
-
-            return argsList.ToArray();
-        }
-
-        static private string ExpandEnvVars(string arguments)
-        {
-            IDictionary id = Environment.GetEnvironmentVariables();
-
-            Regex regex = new Regex("(?<=\\%)(?:[\\w\\.]+)(?=\\%)");
-            MatchCollection matches = regex.Matches(arguments);
-
-            string value = String.Empty;
-            for (int i = 0; i <= (matches.Count - 1); i++)
-            {
-                try
-                {
-                    string key = matches[i].Value;
-                    regex = new Regex(String.Concat("(?i)(?:\\%)(?:" , key , ")(?:\\%)"));
-                    value = id[key].ToString();
-                    arguments = regex.Replace(arguments, value);
-                }
-                catch (NullReferenceException)
-                {
-                    // Collapse unresolved environment variables.
-                    arguments = regex.Replace(arguments, value);
-                }
-            }
-
-            return arguments;
-        }
-    }
-}
diff --git a/src/WixToolset.Core/CompileContext.cs b/src/WixToolset.Core/CompileContext.cs
index 6f19961f..c7a0905e 100644
--- a/src/WixToolset.Core/CompileContext.cs
+++ b/src/WixToolset.Core/CompileContext.cs
@@ -9,7 +9,7 @@ namespace WixToolset.Core
     using WixToolset.Extensibility;
     using WixToolset.Extensibility.Data;
 
-    public class CompileContext : ICompileContext
+    internal class CompileContext : ICompileContext
     {
         internal CompileContext(IServiceProvider serviceProvider)
         {
diff --git a/src/WixToolset.Core/Compiler.cs b/src/WixToolset.Core/Compiler.cs
index 06f477c1..437c1481 100644
--- a/src/WixToolset.Core/Compiler.cs
+++ b/src/WixToolset.Core/Compiler.cs
@@ -22,7 +22,7 @@ namespace WixToolset.Core
     /// <summary>
     /// Compiler of the WiX toolset.
     /// </summary>
-    public sealed class Compiler
+    internal class Compiler
     {
         public const string UpgradeDetectedProperty = "WIX_UPGRADE_DETECTED";
         public const string UpgradePreventedCondition = "NOT WIX_UPGRADE_DETECTED";
@@ -69,7 +69,7 @@ namespace WixToolset.Core
             Icon,
         }
 
-        public Compiler(IServiceProvider serviceProvider)
+        internal Compiler(IServiceProvider serviceProvider)
         {
             this.ServiceProvider = serviceProvider;
 
diff --git a/src/WixToolset.Core/CompilerCore.cs b/src/WixToolset.Core/CompilerCore.cs
index c9165b52..cc881f48 100644
--- a/src/WixToolset.Core/CompilerCore.cs
+++ b/src/WixToolset.Core/CompilerCore.cs
@@ -39,7 +39,7 @@ namespace WixToolset.Core
     /// <summary>
     /// Core class for the compiler.
     /// </summary>
-    internal sealed class CompilerCore
+    internal class CompilerCore
     {
         internal static readonly XNamespace W3SchemaPrefix = "http://www.w3.org/";
         internal static readonly XNamespace WixNamespace = "http://wixtoolset.org/schemas/v4/wxs";
diff --git a/src/WixToolset.Core/Converter.cs b/src/WixToolset.Core/Converter.cs
index fd925f7a..1f83c88f 100644
--- a/src/WixToolset.Core/Converter.cs
+++ b/src/WixToolset.Core/Converter.cs
@@ -15,7 +15,7 @@ namespace WixToolset.Core
     /// <summary>
     /// WiX source code converter.
     /// </summary>
-    public class Converter
+    internal class Converter
     {
         private const string XDocumentNewLine = "\n"; // XDocument normlizes "\r\n" to just "\n".
         private static readonly XNamespace WixNamespace = "http://wixtoolset.org/schemas/v4/wxs";
@@ -65,7 +65,7 @@ namespace WixToolset.Core
         /// <param name="indentationAmount">Indentation value to use when validating leading whitespace.</param>
         /// <param name="errorsAsWarnings">Test errors to display as warnings.</param>
         /// <param name="ignoreErrors">Test errors to ignore.</param>
-        public Converter(IMessaging messaging, int indentationAmount, IEnumerable<string> errorsAsWarnings = null, IEnumerable<string> ignoreErrors = null)
+        internal Converter(IMessaging messaging, int indentationAmount, IEnumerable<string> errorsAsWarnings = null, IEnumerable<string> ignoreErrors = null)
         {
             this.ConvertElementMapping = new Dictionary<XName, Action<XElement>>()
             {
diff --git a/src/WixToolset.Core/Harvester.cs b/src/WixToolset.Core/Harvester.cs
index b9c27418..55d56e64 100644
--- a/src/WixToolset.Core/Harvester.cs
+++ b/src/WixToolset.Core/Harvester.cs
@@ -11,7 +11,7 @@ namespace WixToolset
     /// <summary>
     /// The WiX Toolset harvester.
     /// </summary>
-    public sealed class Harvester
+    public class Harvester
     {
         private HarvesterExtension harvesterExtension;
 
diff --git a/src/WixToolset.Core/HarvesterCore.cs b/src/WixToolset.Core/HarvesterCore.cs
index 92a057d8..70991979 100644
--- a/src/WixToolset.Core/HarvesterCore.cs
+++ b/src/WixToolset.Core/HarvesterCore.cs
@@ -10,7 +10,7 @@ namespace WixToolset.Core
     /// <summary>
     /// The WiX Toolset harvester core.
     /// </summary>
-    public sealed class HarvesterCore : IHarvesterCore
+    public class HarvesterCore : IHarvesterCore
     {
         public IMessaging Messaging { get; set; }
 
diff --git a/src/WixToolset.Core/HeatCore.cs b/src/WixToolset.Core/HeatCore.cs
index 8e02a7b5..d43b5f3d 100644
--- a/src/WixToolset.Core/HeatCore.cs
+++ b/src/WixToolset.Core/HeatCore.cs
@@ -7,7 +7,7 @@ namespace WixToolset.Core
     /// <summary>
     /// The WiX Toolset Harvester application core.
     /// </summary>
-    public sealed class HeatCore : IHeatCore
+    public class HeatCore : IHeatCore
     {
         private Harvester harvester;
         private Mutator mutator;
diff --git a/src/WixToolset.Core/ILocalizer.cs b/src/WixToolset.Core/ILocalizer.cs
new file mode 100644
index 00000000..f15d9ba7
--- /dev/null
+++ b/src/WixToolset.Core/ILocalizer.cs
@@ -0,0 +1,27 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixToolset.Core
+{
+    using System.Xml.Linq;
+    using WixToolset.Data;
+
+    /// <summary>
+    /// Parses localization files and localizes database values.
+    /// </summary>
+    public interface ILocalizer
+    {
+        /// <summary>
+        /// Loads a localization file from a path on disk.
+        /// </summary>
+        /// <param name="path">Path to localization file saved on disk.</param>
+        /// <returns>Returns the loaded localization file.</returns>
+        Localization ParseLocalizationFile(string path);
+
+        /// <summary>
+        /// Loads a localization file from memory.
+        /// </summary>
+        /// <param name="document">Document to parse as localization file.</param>
+        /// <returns>Returns the loaded localization file.</returns>
+        Localization ParseLocalizationFile(XDocument document);
+    }
+}
diff --git a/src/WixToolset.Core/Inscriber.cs b/src/WixToolset.Core/Inscriber.cs
index efe64ad2..649e1661 100644
--- a/src/WixToolset.Core/Inscriber.cs
+++ b/src/WixToolset.Core/Inscriber.cs
@@ -1,6 +1,6 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
 
-namespace WixToolset
+namespace WixToolset.Core
 {
     using System.IO;
     using WixToolset.Data;
@@ -8,7 +8,7 @@ namespace WixToolset
     /// <summary>
     /// Converts a wixout representation of an MSM database into a ComponentGroup the form of WiX source.
     /// </summary>
-    public sealed class Inscriber
+    internal class Inscriber
     {
         /// <summary>
         /// Gets or sets the temp files collection.
diff --git a/src/WixToolset.Core/Layout.cs b/src/WixToolset.Core/Layout.cs
index 28c9d5fc..128efc61 100644
--- a/src/WixToolset.Core/Layout.cs
+++ b/src/WixToolset.Core/Layout.cs
@@ -15,9 +15,9 @@ namespace WixToolset.Core
     /// <summary>
     /// Layout for the WiX toolset.
     /// </summary>
-    public sealed class Layout
+    internal class Layout
     {
-        public Layout(IServiceProvider serviceProvider)
+        internal Layout(IServiceProvider serviceProvider)
         {
             this.ServiceProvider = serviceProvider;
 
diff --git a/src/WixToolset.Core/LayoutContext.cs b/src/WixToolset.Core/LayoutContext.cs
index 172cea65..99ca611a 100644
--- a/src/WixToolset.Core/LayoutContext.cs
+++ b/src/WixToolset.Core/LayoutContext.cs
@@ -7,7 +7,7 @@ namespace WixToolset.Core
     using WixToolset.Extensibility;
     using WixToolset.Extensibility.Data;
 
-    public class LayoutContext : ILayoutContext
+    internal class LayoutContext : ILayoutContext
     {
         internal LayoutContext(IServiceProvider serviceProvider)
         {
diff --git a/src/WixToolset.Core/Librarian.cs b/src/WixToolset.Core/Librarian.cs
index 15efcfcc..abd6c844 100644
--- a/src/WixToolset.Core/Librarian.cs
+++ b/src/WixToolset.Core/Librarian.cs
@@ -15,9 +15,9 @@ namespace WixToolset.Core
     /// <summary>
     /// Core librarian tool.
     /// </summary>
-    public sealed class Librarian
+    internal class Librarian
     {
-        public Librarian(IServiceProvider serviceProvider)
+        internal Librarian(IServiceProvider serviceProvider)
         {
             this.ServiceProvider = serviceProvider;
 
diff --git a/src/WixToolset.Core/LibraryContext.cs b/src/WixToolset.Core/LibraryContext.cs
index 0b09aa93..e61b6ce8 100644
--- a/src/WixToolset.Core/LibraryContext.cs
+++ b/src/WixToolset.Core/LibraryContext.cs
@@ -9,9 +9,9 @@ namespace WixToolset.Core
     using WixToolset.Extensibility.Data;
     using WixToolset.Extensibility.Services;
 
-    public class LibraryContext : ILibraryContext
+    internal class LibraryContext : ILibraryContext
     {
-        public LibraryContext(IServiceProvider serviceProvider)
+        internal LibraryContext(IServiceProvider serviceProvider)
         {
             this.ServiceProvider = serviceProvider;
         }
diff --git a/src/WixToolset.Core/Link/ConnectToFeature.cs b/src/WixToolset.Core/Link/ConnectToFeature.cs
index bc85426a..dd95f2db 100644
--- a/src/WixToolset.Core/Link/ConnectToFeature.cs
+++ b/src/WixToolset.Core/Link/ConnectToFeature.cs
@@ -1,6 +1,6 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
 
-namespace WixToolset.Link
+namespace WixToolset.Core.Link
 {
     using System.Collections.Generic;
     using WixToolset.Data;
@@ -8,7 +8,7 @@ namespace WixToolset.Link
     /// <summary>
     /// Object that connects things (components/modules) to features.
     /// </summary>
-    public sealed class ConnectToFeature
+    internal class ConnectToFeature
     {
         /// <summary>
         /// Creates a new connect to feature.
diff --git a/src/WixToolset.Core/Link/ConnectToFeatureCollection.cs b/src/WixToolset.Core/Link/ConnectToFeatureCollection.cs
index 8dd0d22c..b7874527 100644
--- a/src/WixToolset.Core/Link/ConnectToFeatureCollection.cs
+++ b/src/WixToolset.Core/Link/ConnectToFeatureCollection.cs
@@ -1,6 +1,6 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
 
-namespace WixToolset.Link
+namespace WixToolset.Core.Link
 {
     using System;
     using System.Collections;
@@ -8,7 +8,7 @@ namespace WixToolset.Link
     /// <summary>
     /// Hash collection of connect to feature objects.
     /// </summary>
-    public sealed class ConnectToFeatureCollection : ICollection
+    internal class ConnectToFeatureCollection : ICollection
     {
         private Hashtable collection;
 
diff --git a/src/WixToolset.Core/Link/ConnectToModule.cs b/src/WixToolset.Core/Link/ConnectToModule.cs
index d6a8338e..4380e12c 100644
--- a/src/WixToolset.Core/Link/ConnectToModule.cs
+++ b/src/WixToolset.Core/Link/ConnectToModule.cs
@@ -1,11 +1,11 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
 
-namespace WixToolset.Link
+namespace WixToolset.Core.Link
 {
     /// <summary>
     /// Object that connects things to modules.
     /// </summary>
-    public sealed class ConnectToModule
+    internal class ConnectToModule
     {
         private string childId;
         private string module;
diff --git a/src/WixToolset.Core/Link/ConnectToModuleCollection.cs b/src/WixToolset.Core/Link/ConnectToModuleCollection.cs
index 6595487f..e0f96ffb 100644
--- a/src/WixToolset.Core/Link/ConnectToModuleCollection.cs
+++ b/src/WixToolset.Core/Link/ConnectToModuleCollection.cs
@@ -1,6 +1,6 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
 
-namespace WixToolset.Link
+namespace WixToolset.Core.Link
 {
     using System;
     using System.Collections;
@@ -8,7 +8,7 @@ namespace WixToolset.Link
     /// <summary>
     /// Hash collection of connect to module objects.
     /// </summary>
-    public sealed class ConnectToModuleCollection : ICollection
+    internal class ConnectToModuleCollection : ICollection
     {
         private Hashtable collection;
 
diff --git a/src/WixToolset.Core/Link/ReportConflictingSymbolsCommand.cs b/src/WixToolset.Core/Link/ReportConflictingSymbolsCommand.cs
index 23fac864..8d818ad9 100644
--- a/src/WixToolset.Core/Link/ReportConflictingSymbolsCommand.cs
+++ b/src/WixToolset.Core/Link/ReportConflictingSymbolsCommand.cs
@@ -1,13 +1,13 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
 
-namespace WixToolset.Link
+namespace WixToolset.Core.Link
 {
     using System.Collections.Generic;
     using System.Linq;
     using WixToolset.Data;
     using WixToolset.Extensibility.Services;
 
-    public class ReportConflictingSymbolsCommand
+    internal class ReportConflictingSymbolsCommand
     {
         public ReportConflictingSymbolsCommand(IMessaging messaging, IEnumerable<Symbol> possibleConflicts, IEnumerable<IntermediateSection> resolvedSections)
         {
diff --git a/src/WixToolset.Core/Link/ResolveReferencesCommand.cs b/src/WixToolset.Core/Link/ResolveReferencesCommand.cs
index c05464e9..0188f9ac 100644
--- a/src/WixToolset.Core/Link/ResolveReferencesCommand.cs
+++ b/src/WixToolset.Core/Link/ResolveReferencesCommand.cs
@@ -1,6 +1,6 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
 
-namespace WixToolset.Link
+namespace WixToolset.Core.Link
 {
     using System;
     using System.Collections.Generic;
diff --git a/src/WixToolset.Core/Link/WixGroupingOrdering.cs b/src/WixToolset.Core/Link/WixGroupingOrdering.cs
index 50c4d8d2..4e89e607 100644
--- a/src/WixToolset.Core/Link/WixGroupingOrdering.cs
+++ b/src/WixToolset.Core/Link/WixGroupingOrdering.cs
@@ -16,7 +16,7 @@ namespace WixToolset.Core.Link
     /// <summary>
     /// Grouping and Ordering class of the WiX toolset.
     /// </summary>
-    internal sealed class WixGroupingOrdering
+    internal class WixGroupingOrdering
     {
         private IMessaging messageHandler;
         private List<string> groupTypes;
@@ -679,7 +679,7 @@ namespace WixToolset.Core.Link
             /// <summary>
             /// Helper IComparer class to make ordering easier.
             /// </summary>
-            internal sealed class AfterItemComparer : IComparer<Item>
+            internal class AfterItemComparer : IComparer<Item>
             {
                 public int Compare(Item x, Item y)
                 {
diff --git a/src/WixToolset.Core/LinkContext.cs b/src/WixToolset.Core/LinkContext.cs
index 7576ca3f..f45a3411 100644
--- a/src/WixToolset.Core/LinkContext.cs
+++ b/src/WixToolset.Core/LinkContext.cs
@@ -8,7 +8,7 @@ namespace WixToolset.Core
     using WixToolset.Extensibility;
     using WixToolset.Extensibility.Data;
 
-    public class LinkContext : ILinkContext
+    internal class LinkContext : ILinkContext
     {
         internal LinkContext(IServiceProvider serviceProvider)
         {
diff --git a/src/WixToolset.Core/Linker.cs b/src/WixToolset.Core/Linker.cs
index 4d1a6965..04188e53 100644
--- a/src/WixToolset.Core/Linker.cs
+++ b/src/WixToolset.Core/Linker.cs
@@ -14,12 +14,11 @@ namespace WixToolset.Core
     using WixToolset.Extensibility;
     using WixToolset.Extensibility.Data;
     using WixToolset.Extensibility.Services;
-    using WixToolset.Link;
 
     /// <summary>
     /// Linker core of the WiX toolset.
     /// </summary>
-    public sealed class Linker
+    internal class Linker
     {
         private static readonly char[] colonCharacter = ":".ToCharArray();
         private static readonly string emptyGuid = Guid.Empty.ToString("B");
@@ -29,7 +28,7 @@ namespace WixToolset.Core
         /// <summary>
         /// Creates a linker.
         /// </summary>
-        public Linker(IServiceProvider serviceProvider)
+        internal Linker(IServiceProvider serviceProvider)
         {
             this.ServiceProvider = serviceProvider;
             this.Messaging = this.ServiceProvider.GetService<IMessaging>();
diff --git a/src/WixToolset.Core/Localizer.cs b/src/WixToolset.Core/Localizer.cs
index cb9a4406..a545f844 100644
--- a/src/WixToolset.Core/Localizer.cs
+++ b/src/WixToolset.Core/Localizer.cs
@@ -11,31 +11,25 @@ namespace WixToolset.Core
     using WixToolset.Extensibility;
     using WixToolset.Extensibility.Services;
 
-    /// <summary>
-    /// Parses localization files and localizes database values.
-    /// </summary>
-    public sealed class Localizer
+    internal class Localizer : ILocalizer
     {
         public static readonly XNamespace WxlNamespace = "http://wixtoolset.org/schemas/v4/wxl";
         private static string XmlElementName = "WixLocalization";
 
-        /// <summary>
-        /// Loads a localization file from a path on disk.
-        /// </summary>
-        /// <param name="path">Path to localization file saved on disk.</param>
-        /// <returns>Returns the loaded localization file.</returns>
-        public static Localization ParseLocalizationFile(IMessaging messaging, string path)
+        internal Localizer(IServiceProvider serviceProvider)
+        {
+            this.Messaging = serviceProvider.GetService<IMessaging>();
+        }
+
+        private IMessaging Messaging { get; }
+
+        public Localization ParseLocalizationFile(string path)
         {
             var document = XDocument.Load(path);
-            return ParseLocalizationFile(messaging, document);
+            return ParseLocalizationFile(document);
         }
 
-        /// <summary>
-        /// Loads a localization file from memory.
-        /// </summary>
-        /// <param name="document">Document to parse as localization file.</param>
-        /// <returns>Returns the loaded localization file.</returns>
-        public static Localization ParseLocalizationFile(IMessaging messaging, XDocument document)
+        public Localization ParseLocalizationFile(XDocument document)
         {
             XElement root = document.Root;
             Localization localization = null;
@@ -45,23 +39,23 @@ namespace WixToolset.Core
             {
                 if (Localizer.WxlNamespace == root.Name.Namespace)
                 {
-                    localization = ParseWixLocalizationElement(messaging, root);
+                    localization = ParseWixLocalizationElement(this.Messaging, root);
                 }
                 else // invalid or missing namespace
                 {
                     if (null == root.Name.Namespace)
                     {
-                        messaging.Write(ErrorMessages.InvalidWixXmlNamespace(sourceLineNumbers, Localizer.XmlElementName, Localizer.WxlNamespace.NamespaceName));
+                        this.Messaging.Write(ErrorMessages.InvalidWixXmlNamespace(sourceLineNumbers, Localizer.XmlElementName, Localizer.WxlNamespace.NamespaceName));
                     }
                     else
                     {
-                        messaging.Write(ErrorMessages.InvalidWixXmlNamespace(sourceLineNumbers, Localizer.XmlElementName, root.Name.LocalName, Localizer.WxlNamespace.NamespaceName));
+                        this.Messaging.Write(ErrorMessages.InvalidWixXmlNamespace(sourceLineNumbers, Localizer.XmlElementName, root.Name.LocalName, Localizer.WxlNamespace.NamespaceName));
                     }
                 }
             }
             else
             {
-                messaging.Write(ErrorMessages.InvalidDocumentElement(sourceLineNumbers, root.Name.LocalName, "localization", Localizer.XmlElementName));
+                this.Messaging.Write(ErrorMessages.InvalidDocumentElement(sourceLineNumbers, root.Name.LocalName, "localization", Localizer.XmlElementName));
             }
 
             return localization;
diff --git a/src/WixToolset.Core/Mutator.cs b/src/WixToolset.Core/Mutator.cs
index 7f1af13a..cee17736 100644
--- a/src/WixToolset.Core/Mutator.cs
+++ b/src/WixToolset.Core/Mutator.cs
@@ -10,7 +10,7 @@ namespace WixToolset.Core
     /// <summary>
     /// The WiX Toolset mutator.
     /// </summary>
-    public sealed class Mutator
+    public class Mutator
     {
         private SortedList extensions;
         private string extensionArgument;
diff --git a/src/WixToolset.Core/OptimizeCA.cs b/src/WixToolset.Core/OptimizeCA.cs
index efd07299..ba17604d 100644
--- a/src/WixToolset.Core/OptimizeCA.cs
+++ b/src/WixToolset.Core/OptimizeCA.cs
@@ -8,7 +8,7 @@ namespace WixToolset.Core
     /// Values for the OptimizeCA MsiPatchMetdata property, which indicates whether custom actions can be skipped when applying the patch.
     /// </summary>
     [Flags]
-    public enum OptimizeCA
+    internal enum OptimizeCA
     {
         /// <summary>
         /// No custom actions are skipped.
diff --git a/src/WixToolset.Core/Preprocess/IfContext.cs b/src/WixToolset.Core/Preprocess/IfContext.cs
index e7c6e6f5..91173c29 100644
--- a/src/WixToolset.Core/Preprocess/IfContext.cs
+++ b/src/WixToolset.Core/Preprocess/IfContext.cs
@@ -5,7 +5,7 @@ namespace WixToolset.Core.Preprocess
     /// <summary>
     /// Context for an if statement in the preprocessor.
     /// </summary>
-    internal sealed class IfContext
+    internal class IfContext
     {
         private bool keep;
 
diff --git a/src/WixToolset.Core/Preprocess/ProcessedStreamEventHandler.cs b/src/WixToolset.Core/Preprocess/ProcessedStreamEventHandler.cs
index 434590d2..b2a4ddb1 100644
--- a/src/WixToolset.Core/Preprocess/ProcessedStreamEventHandler.cs
+++ b/src/WixToolset.Core/Preprocess/ProcessedStreamEventHandler.cs
@@ -32,12 +32,12 @@ namespace WixToolset.Core.Preprocess
         /// Gets the full path of the source file.
         /// </summary>
         /// <value>The full path of the source file.</value>
-        public string SourceFile { get; private set; }
+        public string SourceFile { get; }
 
         /// <summary>
         /// Gets the preprocessed output stream.
         /// </summary>
         /// <value>The the preprocessed output stream.</value>
-        public XDocument Document { get; private set; }
+        public XDocument Document { get; }
     }
 }
diff --git a/src/WixToolset.Core/Preprocessor.cs b/src/WixToolset.Core/Preprocessor.cs
index aca954bd..acba0b5f 100644
--- a/src/WixToolset.Core/Preprocessor.cs
+++ b/src/WixToolset.Core/Preprocessor.cs
@@ -20,24 +20,24 @@ namespace WixToolset.Core
     /// <summary>
     /// Preprocessor object
     /// </summary>
-    public sealed class Preprocessor
+    internal class Preprocessor
     {
-        private readonly Regex defineRegex = new Regex(@"^\s*(?<varName>.+?)\s*(=\s*(?<varValue>.+?)\s*)?$", RegexOptions.Compiled | RegexOptions.Singleline | RegexOptions.ExplicitCapture);
-        private readonly Regex pragmaRegex = new Regex(@"^\s*(?<pragmaName>.+?)(?<pragmaValue>[\s\(].+?)?$", RegexOptions.Compiled | RegexOptions.Singleline | RegexOptions.ExplicitCapture);
+        private static readonly Regex DefineRegex = new Regex(@"^\s*(?<varName>.+?)\s*(=\s*(?<varValue>.+?)\s*)?$", RegexOptions.Compiled | RegexOptions.Singleline | RegexOptions.ExplicitCapture);
+        private static readonly Regex PragmaRegex = new Regex(@"^\s*(?<pragmaName>.+?)(?<pragmaValue>[\s\(].+?)?$", RegexOptions.Compiled | RegexOptions.Singleline | RegexOptions.ExplicitCapture);
 
-        private readonly XmlReaderSettings DocumentXmlReaderSettings = new XmlReaderSettings()
+        private static readonly XmlReaderSettings DocumentXmlReaderSettings = new XmlReaderSettings()
         {
             ValidationFlags = System.Xml.Schema.XmlSchemaValidationFlags.None,
             XmlResolver = null,
         };
-        private readonly XmlReaderSettings FragmentXmlReaderSettings = new XmlReaderSettings()
+        private static readonly XmlReaderSettings FragmentXmlReaderSettings = new XmlReaderSettings()
         {
             ConformanceLevel = ConformanceLevel.Fragment,
             ValidationFlags = System.Xml.Schema.XmlSchemaValidationFlags.None,
             XmlResolver = null,
         };
 
-        public Preprocessor(IServiceProvider serviceProvider)
+        internal Preprocessor(IServiceProvider serviceProvider)
         {
             this.ServiceProvider = serviceProvider;
 
@@ -584,7 +584,7 @@ namespace WixToolset.Core
         /// <param name="originalDefine">Text from source.</param>
         private void PreprocessDefine(string originalDefine)
         {
-            var match = defineRegex.Match(originalDefine);
+            var match = DefineRegex.Match(originalDefine);
 
             if (!match.Success)
             {
@@ -791,7 +791,7 @@ namespace WixToolset.Core
         /// <param name="pragmaText">Text from source.</param>
         private void PreprocessPragma(string pragmaText, XContainer parent)
         {
-            var match = pragmaRegex.Match(pragmaText);
+            var match = PragmaRegex.Match(pragmaText);
 
             if (!match.Success)
             {
diff --git a/src/WixToolset.Core/ResolveContext.cs b/src/WixToolset.Core/ResolveContext.cs
index 65b991ea..cadc6678 100644
--- a/src/WixToolset.Core/ResolveContext.cs
+++ b/src/WixToolset.Core/ResolveContext.cs
@@ -9,7 +9,7 @@ namespace WixToolset.Core
     using WixToolset.Extensibility.Data;
     using WixToolset.Extensibility.Services;
 
-    public class ResolveContext : IResolveContext
+    internal class ResolveContext : IResolveContext
     {
         internal ResolveContext(IServiceProvider serviceProvider)
         {
diff --git a/src/WixToolset.Core/Resolver.cs b/src/WixToolset.Core/Resolver.cs
index 5e283f2c..12cb375b 100644
--- a/src/WixToolset.Core/Resolver.cs
+++ b/src/WixToolset.Core/Resolver.cs
@@ -15,9 +15,9 @@ namespace WixToolset.Core
     /// <summary>
     /// Resolver for the WiX toolset.
     /// </summary>
-    public sealed class Resolver
+    internal class Resolver
     {
-        public Resolver(IServiceProvider serviceProvider)
+        internal Resolver(IServiceProvider serviceProvider)
         {
             this.ServiceProvider = serviceProvider;
 
@@ -26,7 +26,7 @@ namespace WixToolset.Core
 
         private IServiceProvider ServiceProvider { get; }
 
-        public IMessaging Messaging { get; }
+        private IMessaging Messaging { get; }
 
         public IEnumerable<BindPath> BindPaths { get; set; }
 
diff --git a/src/WixToolset.Core/SourceFile.cs b/src/WixToolset.Core/SourceFile.cs
index f1064513..d7ea7a50 100644
--- a/src/WixToolset.Core/SourceFile.cs
+++ b/src/WixToolset.Core/SourceFile.cs
@@ -2,8 +2,6 @@
 
 namespace WixToolset.Core
 {
-    using System.IO;
-
     internal class SourceFile
     {
         public SourceFile(string sourcePath, string outputPath)
@@ -12,8 +10,8 @@ namespace WixToolset.Core
             this.OutputPath = outputPath;
         }
 
-        public string OutputPath { get; set; }
+        public string OutputPath { get; }
 
-        public string SourcePath { get; set; }
+        public string SourcePath { get; }
     }
 }
diff --git a/src/WixToolset.Core/WixToolsetServiceProvider.cs b/src/WixToolset.Core/WixToolsetServiceProvider.cs
index ffcdbdd1..9278ddc3 100644
--- a/src/WixToolset.Core/WixToolsetServiceProvider.cs
+++ b/src/WixToolset.Core/WixToolsetServiceProvider.cs
@@ -10,7 +10,7 @@ namespace WixToolset.Core
     using WixToolset.Extensibility.Data;
     using WixToolset.Extensibility.Services;
 
-    public class WixToolsetServiceProvider : IServiceProvider
+    public sealed class WixToolsetServiceProvider : IServiceProvider
     {
         public WixToolsetServiceProvider()
         {
@@ -36,6 +36,9 @@ namespace WixToolset.Core
                 { typeof(IBindContext), (provider, singletons) => new BindContext(provider) },
                 { typeof(ILayoutContext), (provider, singletons) => new LayoutContext(provider) },
                 { typeof(IInscribeContext), (provider, singletons) => new InscribeContext(provider) },
+
+                // Internal implementations.
+                { typeof(ILocalizer), (provider, singletons) => new Localizer(provider) },
             };
 
             this.Singletons = new Dictionary<Type, object>();
diff --git a/src/WixToolset.Core/WixVariableResolver.cs b/src/WixToolset.Core/WixVariableResolver.cs
index 8ac35e99..75851a56 100644
--- a/src/WixToolset.Core/WixVariableResolver.cs
+++ b/src/WixToolset.Core/WixVariableResolver.cs
@@ -12,7 +12,7 @@ namespace WixToolset.Core
     /// <summary>
     /// WiX variable resolver.
     /// </summary>
-    internal sealed class WixVariableResolver : IVariableResolver
+    internal class WixVariableResolver : IVariableResolver
     {
         private readonly Dictionary<string, BindVariable> locVariables;
         private readonly Dictionary<string, BindVariable> wixVariables;