Made Plugin Folder Unit tests & Expanding enviroment search (#6600)

* Made Plugin Folder Unit tests. Fixes '>' not recursive searching (with max). Added that paths with an UnauthorizedAccessException are ignored. Added expanding enviroment search.

* Fixed some merging errors

* Added feedback from review

* Made the change that  ryanbodrug-microsoft suggested

* Stupid merge request... fixed

Co-authored-by: p-storm <paul.de.man@gmail.com>

src/modules/launcher/Plugins/Microsoft.Plugin.Folder/Sources/Path/DisplayFileInfo.cs

@@ -0,0 +1,42 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+
+namespace Microsoft.Plugin.Folder.Sources
+{
+    public struct DisplayFileInfo : IEquatable<DisplayFileInfo>
+    {
+        public string Name { get; set; }
+
+        public string FullName { get; set; }
+
+        public DisplayType Type { get; set; }
+
+        public override bool Equals(object obj)
+        {
+            return obj is DisplayFileInfo other && Equals(other);
+        }
+
+        public override int GetHashCode()
+        {
+            return HashCode.Combine(Name, FullName, (int)Type);
+        }
+
+        public bool Equals(DisplayFileInfo other)
+        {
+            return Name == other.Name && FullName == other.FullName && Type == other.Type;
+        }
+
+        public static bool operator ==(DisplayFileInfo a, DisplayFileInfo b)
+        {
+            return a.Equals(b);
+        }
+
+        public static bool operator !=(DisplayFileInfo a, DisplayFileInfo b)
+        {
+            return !(a == b);
+        }
+    }
+}

src/modules/launcher/Plugins/Microsoft.Plugin.Folder/Sources/Path/DisplayType.cs

@@ -0,0 +1,12 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace Microsoft.Plugin.Folder.Sources
+{
+    public enum DisplayType
+    {
+        Directory,
+        File,
+    }
+}

src/modules/launcher/Plugins/Microsoft.Plugin.Folder/Sources/Path/DriveInformation.cs

@@ -0,0 +1,26 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
+using System.Linq;
+
+namespace Microsoft.Plugin.Folder.Sources
+{
+    internal class DriveInformation : IDriveInformation
+    {
+        private static readonly List<string> DriverNames = InitialDriverList().ToList();
+
+        [System.Diagnostics.CodeAnalysis.SuppressMessage("Globalization", "CA1308:Normalize strings to uppercase", Justification = "Do not want to change the behavior of the application, but want to enforce static analysis")]
+        private static IEnumerable<string> InitialDriverList()
+        {
+            var directorySeparatorChar = System.IO.Path.DirectorySeparatorChar;
+            return DriveInfo.GetDrives()
+                .Select(driver => driver.Name.ToLower(CultureInfo.InvariantCulture).TrimEnd(directorySeparatorChar));
+        }
+
+        public IEnumerable<string> GetDriveNames() => DriverNames;
+    }
+}

src/modules/launcher/Plugins/Microsoft.Plugin.Folder/Sources/Path/FolderHelper.cs

@@ -0,0 +1,81 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Linq;
+
+namespace Microsoft.Plugin.Folder.Sources
+{
+    public class FolderHelper : IFolderHelper
+    {
+        private readonly IDriveInformation _driveInformation;
+        private readonly IFolderLinks _folderLinks;
+
+        public FolderHelper(IDriveInformation driveInformation, IFolderLinks folderLinks)
+        {
+            _driveInformation = driveInformation;
+            _folderLinks = folderLinks;
+        }
+
+        public IEnumerable<FolderLink> GetUserFolderResults(string query)
+        {
+            if (query == null)
+            {
+                throw new ArgumentNullException(paramName: nameof(query));
+            }
+
+            return _folderLinks.FolderLinks()
+                .Where(x => x.Nickname.StartsWith(query, StringComparison.OrdinalIgnoreCase));
+        }
+
+        public bool IsDriveOrSharedFolder(string search)
+        {
+            if (search == null)
+            {
+                throw new ArgumentNullException(nameof(search));
+            }
+
+            if (search.StartsWith(@"\\", StringComparison.InvariantCulture))
+            { // share folder
+                return true;
+            }
+
+            var driverNames = _driveInformation.GetDriveNames()
+                .ToImmutableArray();
+
+            if (driverNames.Any())
+            {
+                if (driverNames.Any(dn => search.StartsWith(dn, StringComparison.InvariantCultureIgnoreCase)))
+                {
+                    // normal drive letter
+                    return true;
+                }
+            }
+            else
+            {
+                if (search.Length > 2 && ValidDriveLetter(search[0]) && search[1] == ':')
+                { // when we don't have the drive letters we can try...
+                    return true; // we don't know so let's give it the possibility
+                }
+            }
+
+            return false;
+        }
+
+        /// <summary>
+        /// This check is needed because char.IsLetter accepts more than [A-z]
+        /// </summary>
+        public static bool ValidDriveLetter(char c)
+        {
+            return c <= 122 && char.IsLetter(c);
+        }
+
+        public static string Expand(string search)
+        {
+            return Environment.ExpandEnvironmentVariables(search);
+        }
+    }
+}

src/modules/launcher/Plugins/Microsoft.Plugin.Folder/Sources/Path/IDriveInformation.cs

@@ -0,0 +1,12 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+using System.Collections.Generic;
+
+namespace Microsoft.Plugin.Folder.Sources
+{
+    public interface IDriveInformation
+    {
+        IEnumerable<string> GetDriveNames();
+    }
+}

src/modules/launcher/Plugins/Microsoft.Plugin.Folder/Sources/Path/IFolderHelper.cs

@@ -0,0 +1,11 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace Microsoft.Plugin.Folder.Sources
+{
+    public interface IFolderHelper
+    {
+        bool IsDriveOrSharedFolder(string search);
+    }
+}