Packages install path can again be edited from preferences window

src/NuGetForUnity/Editor/Configuration/ConfigurationManager.cs

@@ -34,8 +34,16 @@ public static class ConfigurationManager
 
         static ConfigurationManager()
         {
-            NugetConfigFileDirectoryPath = UnityPathHelper.AbsoluteAssetsPath;
-            NugetConfigFilePath = Path.Combine(NugetConfigFileDirectoryPath, NugetConfigFile.FileName);
+            NugetConfigFilePath = Path.Combine(UnityPathHelper.AbsoluteUnityPackagesNugetPath, NugetConfigFile.FileName);
+            if (File.Exists(NugetConfigFilePath))
+            {
+                NugetConfigFileDirectoryPath = UnityPathHelper.AbsoluteUnityPackagesNugetPath;
+            }
+            else
+            {
+                NugetConfigFilePath = Path.Combine(UnityPathHelper.AbsoluteAssetsPath, NugetConfigFile.FileName);
+                NugetConfigFileDirectoryPath = UnityPathHelper.AbsoluteAssetsPath;
+            }
         }
 
         /// <summary>
@@ -45,7 +53,7 @@ static ConfigurationManager()
         ///     <see cref="NugetConfigFile" />.
         /// </remarks>
         [NotNull]
-        public static string NugetConfigFilePath { get; }
+        public static string NugetConfigFilePath { get; private set; }
 
         /// <summary>
         ///     Gets the loaded NuGet.config file that holds the settings for NuGet.
@@ -69,7 +77,7 @@ public static NugetConfigFile NugetConfigFile
         ///     Gets the path to the directory containing the NuGet.config file.
         /// </summary>
         [NotNull]
-        internal static string NugetConfigFileDirectoryPath { get; }
+        internal static string NugetConfigFileDirectoryPath { get; private set; }
 
         /// <summary>
         ///     Gets a value indicating whether verbose logging is enabled.
@@ -207,5 +215,28 @@ public static INugetPackage GetSpecificPackage([NotNull] INugetPackageIdentifier
         {
             return ActivePackageSource.GetSpecificPackage(nugetPackageIdentifier);
         }
+
+        /// <summary>
+        ///     Moves the Nuget.config under newPlacement and updated local properties to point to it.
+        /// </summary>
+        /// <param name="newInstallLocation">New placement for configs.</param>
+        internal static void MoveConfig(PackageInstallLocation newInstallLocation)
+        {
+            NugetConfigFile.ChangeInstallLocation(newInstallLocation);
+            var newConfigsPath = newInstallLocation == PackageInstallLocation.InPackagesFolder ?
+                UnityPathHelper.AbsoluteUnityPackagesNugetPath :
+                UnityPathHelper.AbsoluteAssetsPath;
+            var newConfigFilePath = Path.Combine(newConfigsPath, NugetConfigFile.FileName);
+
+            File.Move(NugetConfigFilePath, newConfigFilePath);
+            var configMeta = NugetConfigFilePath + ".meta";
+            if (File.Exists(configMeta))
+            {
+                File.Move(configMeta, newConfigFilePath + ".meta");
+            }
+
+            NugetConfigFilePath = newConfigFilePath;
+            NugetConfigFileDirectoryPath = newConfigsPath;
+        }
     }
 }

src/NuGetForUnity/Editor/Configuration/NugetConfigFile.cs

@@ -60,11 +60,17 @@ public class NugetConfigFile
 
         private const string SupportsPackageIdSearchFilterAttributeName = "supportsPackageIdSearchFilter";
 
-        /// <summary>
-        ///     The incomplete path that is saved.  The path is expanded and made public via the property above.
-        /// </summary>
-        [CanBeNull]
-        private string savedRepositoryPath;
+        [NotNull]
+        private readonly string unityPackagesNugetInstallPath = Path.Combine(UnityPathHelper.AbsoluteUnityPackagesNugetPath, "InstalledPackages");
+
+        [NotNull]
+        private string configuredRepositoryPath = "Packages";
+
+        [NotNull]
+        private string packagesConfigDirectoryPath = Application.dataPath;
+
+        [NotNull]
+        private string repositoryPath = Path.GetFullPath(Path.Combine(Application.dataPath, "Packages"));
 
         /// <summary>
         ///     Gets the list of package sources that are defined in the NuGet.config file.
@@ -87,7 +93,35 @@ public class NugetConfigFile
         ///     Gets the absolute path where packages are to be installed.
         /// </summary>
         [NotNull]
-        public string RepositoryPath { get; private set; } = Path.GetFullPath(Path.Combine(Application.dataPath, "Packages"));
+        public string RepositoryPath
+        {
+            get => InstallLocation == PackageInstallLocation.InPackagesFolder ? unityPackagesNugetInstallPath : repositoryPath;
+
+            private set => repositoryPath = value;
+        }
+
+        /// <summary>
+        ///     Gets or sets the incomplete path that is saved.  The path is expanded and made public via the property above.
+        /// </summary>
+        [NotNull]
+        public string ConfiguredRepositoryPath
+        {
+            get => configuredRepositoryPath;
+
+            set
+            {
+                configuredRepositoryPath = value;
+
+                var expandedPath = Environment.ExpandEnvironmentVariables(value);
+
+                if (!Path.IsPathRooted(expandedPath))
+                {
+                    expandedPath = Path.Combine(Application.dataPath, expandedPath);
+                }
+
+                RepositoryPath = Path.GetFullPath(expandedPath.TrimEnd(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar));
+            }
+        }
 
         /// <summary>
         ///     Gets the default package source to push NuGet packages to.
@@ -121,7 +155,15 @@ public class NugetConfigFile
         ///     Gets or sets absolute path to directory containing packages.config file.
         /// </summary>
         [NotNull]
-        public string PackagesConfigDirectoryPath { get; set; } = Application.dataPath;
+        public string PackagesConfigDirectoryPath
+        {
+            get =>
+                InstallLocation == PackageInstallLocation.InPackagesFolder ?
+                    UnityPathHelper.AbsoluteUnityPackagesNugetPath :
+                    packagesConfigDirectoryPath;
+
+            set => packagesConfigDirectoryPath = value;
+        }
 
         /// <summary>
         ///     Gets the relative path to directory containing packages.config file. The path is relative to the folder containing the 'NuGet.config' file.
@@ -144,6 +186,11 @@ public string RelativePackagesConfigDirectoryPath
         /// </summary>
         public int RequestTimeoutSeconds { get; set; } = DefaultRequestTimeout;
 
+        /// <summary>
+        ///     Gets the value that tells the system how to determine where the packages are to be installed and configurations are to be stored.
+        /// </summary>
+        internal PackageInstallLocation InstallLocation { get; private set; }
+
         /// <summary>
         ///     Gets the list of enabled plugins.
         /// </summary>
@@ -297,18 +344,13 @@ public static NugetConfigFile Load([NotNull] string filePath)
                 var key = add.Attribute("key")?.Value;
                 var value = add.Attribute("value")?.Value ?? throw new InvalidOperationException($"config misses 'value' attribute. Element:\n{add}");
 
-                if (string.Equals(key, "repositoryPath", StringComparison.OrdinalIgnoreCase))
+                if (string.Equals(key, "packageInstallLocation", StringComparison.OrdinalIgnoreCase))
                 {
-                    configFile.savedRepositoryPath = value;
-                    configFile.RepositoryPath = Environment.ExpandEnvironmentVariables(value);
-
-                    if (!Path.IsPathRooted(configFile.RepositoryPath))
-                    {
-                        configFile.RepositoryPath = Path.Combine(Application.dataPath, configFile.RepositoryPath);
-                    }
-
-                    configFile.RepositoryPath = Path.GetFullPath(
-                        configFile.RepositoryPath.TrimEnd(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar));
+                    configFile.InstallLocation = (PackageInstallLocation)Enum.Parse(typeof(PackageInstallLocation), value);
+                }
+                else if (string.Equals(key, "repositoryPath", StringComparison.OrdinalIgnoreCase))
+                {
+                    configFile.ConfiguredRepositoryPath = value;
                 }
                 else if (string.Equals(key, "DefaultPushSource", StringComparison.OrdinalIgnoreCase))
                 {
@@ -362,6 +404,7 @@ public static NugetConfigFile CreateDefaultFile([NotNull] string filePath)
     <add key=""All"" value=""(Aggregate source)"" />
   </activePackageSource>
   <config>
+    <add key=""packageInstallLocation"" value=""CustomWithinAssets"" />
     <add key=""repositoryPath"" value=""./Packages"" />
     <add key=""PackagesConfigDirectoryPath"" value=""."" />
     <add key=""slimRestore"" value=""true"" />
@@ -454,18 +497,23 @@ public void Save([NotNull] string filePath)
 
             var config = new XElement("config");
 
-            if (!string.IsNullOrEmpty(savedRepositoryPath))
+            addElement = new XElement("add");
+            addElement.Add(new XAttribute("key", "packageInstallLocation"));
+            addElement.Add(new XAttribute("value", InstallLocation.ToString()));
+            config.Add(addElement);
+
+            if (!string.IsNullOrEmpty(ConfiguredRepositoryPath))
             {
                 // save the un-expanded repository path
                 addElement = new XElement("add");
                 addElement.Add(new XAttribute("key", "repositoryPath"));
-                addElement.Add(new XAttribute("value", savedRepositoryPath));
+                addElement.Add(new XAttribute("value", ConfiguredRepositoryPath));
                 config.Add(addElement);
             }
 
             addElement = new XElement("add");
             addElement.Add(new XAttribute("key", PackagesConfigDirectoryPathConfigKey));
-            addElement.Add(new XAttribute("value", RelativePackagesConfigDirectoryPath));
+            addElement.Add(new XAttribute("value", PathHelper.GetRelativePath(Application.dataPath, packagesConfigDirectoryPath)));
             config.Add(addElement);
 
             // save the default push source
@@ -553,5 +601,28 @@ public void Save([NotNull] string filePath)
 
             configFile.Save(filePath);
         }
+
+        /// <summary>
+        ///     Changes the package install location config and also moves the packages.config to the new location.
+        /// </summary>
+        /// <param name="newInstallLocation">New install location to set.</param>
+        internal void ChangeInstallLocation(PackageInstallLocation newInstallLocation)
+        {
+            if (newInstallLocation == InstallLocation)
+            {
+                return;
+            }
+
+            var oldPackagesConfigPath = PackagesConfigFilePath;
+            InstallLocation = newInstallLocation;
+            UnityPathHelper.EnsurePackageInstallDirectoryIsSetup();
+            var newConfigPath = PackagesConfigFilePath;
+            File.Move(oldPackagesConfigPath, newConfigPath);
+            var configMeta = oldPackagesConfigPath + ".meta";
+            if (File.Exists(configMeta))
+            {
+                File.Move(configMeta, newConfigPath + ".meta");
+            }
+        }
     }
 }

src/NuGetForUnity/Editor/Configuration/PackageInstallLocation.cs

@@ -0,0 +1,22 @@
+namespace NugetForUnity.Configuration
+{
+    /// <summary>
+    ///     Tells the system how to determine where the packages are to be installed and configurations are to be stored.
+    /// </summary>
+    internal enum PackageInstallLocation
+    {
+        /// <summary>
+        ///     This option will place Nuget.config into the Assets folder and will allow the user to
+        ///     specify custom location within Assets folder for packages.config and package installation
+        ///     folder.
+        /// </summary>
+        CustomWithinAssets,
+
+        /// <summary>
+        ///     This options will place the Nuget.config and packages.config under Packages/nuget-packages
+        ///     and will install the packages under Packages/nuget-packages/InstalledPackages.
+        /// </summary>
+        /// .
+        InPackagesFolder,
+    }
+}

src/NuGetForUnity/Editor/Configuration/PackagesConfigFile.cs

@@ -172,7 +172,9 @@ internal static void Move([NotNull] string newPath)
             var nugetConfig = ConfigurationManager.NugetConfigFile;
             var oldFilePath = nugetConfig.PackagesConfigFilePath;
             var oldPath = nugetConfig.PackagesConfigDirectoryPath;
-            nugetConfig.PackagesConfigDirectoryPath = newPath;
+
+            // We need to make sure saved path is using forward slashes so it works on all systems
+            nugetConfig.PackagesConfigDirectoryPath = newPath.Replace("\\", "/");
             var newFilePath = Path.GetFullPath(Path.Combine(newPath, FileName));
             try
             {

src/NuGetForUnity/Editor/Helper/UnityPathHelper.cs

@@ -3,6 +3,7 @@
 using System;
 using System.IO;
 using JetBrains.Annotations;
+using NugetForUnity.Configuration;
 using UnityEngine;
 
 #region No ReShaper
@@ -28,8 +29,15 @@ static UnityPathHelper()
         {
             AbsoluteAssetsPath = Path.GetFullPath(Application.dataPath);
             AbsoluteProjectPath = Path.GetDirectoryName(AbsoluteAssetsPath) ?? throw new InvalidOperationException("Can't detect project root.");
+            AbsoluteUnityPackagesNugetPath = Path.GetFullPath(Path.Combine(AbsoluteAssetsPath, "../Packages/nuget-packages"));
         }
 
+        /// <summary>
+        ///     Gets the absolute path to 'project root'/Packages/nuget-packages.
+        /// </summary>
+        [NotNull]
+        internal static string AbsoluteUnityPackagesNugetPath { get; }
+
         /// <summary>
         ///     Gets the absolute path to the Unity-Project 'Assets' directory.
         /// </summary>
@@ -53,10 +61,42 @@ internal static bool IsPathInAssets([NotNull] string path)
             return !Path.IsPathRooted(assetsRelativePath) && !assetsRelativePath.StartsWith("..", StringComparison.Ordinal);
         }
 
+        /// <summary>
+        ///     Checks if given relative path is a valid for packages installations.
+        /// </summary>
+        /// <param name="path">Relative path to check.</param>
+        /// <returns>True if path is within Assets folder or Packages subfolder, false otherwise.</returns>
+        internal static bool IsValidInstallPath([NotNull] string path)
+        {
+            return !Path.IsPathRooted(path) && !path.StartsWith("..", StringComparison.Ordinal);
+        }
+
+        /// <summary>
+        ///     Ensures that the package install directory exists and in case it is under Unity's
+        ///     Packages folder that it contains a dummy package.json file so that Unity can see it.
+        /// </summary>
+        internal static void EnsurePackageInstallDirectoryIsSetup()
+        {
+            Directory.CreateDirectory(ConfigurationManager.NugetConfigFile.RepositoryPath);
+
+            if (ConfigurationManager.NugetConfigFile.InstallLocation == PackageInstallLocation.CustomWithinAssets)
+            {
+                return;
+            }
+
+            var jsonPath = Path.Combine(AbsoluteUnityPackagesNugetPath, "package.json");
+            if (!File.Exists(jsonPath))
+            {
+                File.WriteAllText(
+                    jsonPath,
+                    @"{ ""name"": ""nuget-packages"",""version"": ""1.0.0"",""displayName"": ""NuGetPackages"", ""description"": ""NuGetPackages"", ""dependencies"": {}}");
+            }
+        }
+
         /// <summary>
         ///     Returns the path relative to Assets directory, or <c>"."</c> if it is the Assets directory.
         /// </summary>
-        /// <param name="path">The path of witch we calculate the relative path of.</param>
+        /// <param name="path">The path of which we calculate the relative path of.</param>
         /// <returns>The path relative to Assets directory, or <c>"."</c> if it is the Assets directory.</returns>
         [NotNull]
         private static string GetAssetsRelativePath([NotNull] string path)

src/NuGetForUnity/Editor/NugetPackageInstaller.cs

@@ -159,7 +159,7 @@ private static bool Install([NotNull] INugetPackage package, bool refreshAssets,
 
                 if (File.Exists(cachedPackagePath))
                 {
-                    var baseDirectory = Path.Combine(ConfigurationManager.NugetConfigFile.RepositoryPath, $"{package.Id}.{package.Version}");
+                    var baseDirectory = package.GetPackageInstallPath();
 
                     // unzip the package
                     using (var zip = ZipFile.OpenRead(cachedPackagePath))