Nullable: System.IO (dotnet#23732)

stephentoub · web-flow · commit 5ce35bf3d445 · 2019-04-09T12:10:28.000-04:00
* Nullable: System.IO

Everything exception StreamReader, StreamWriter, BinaryReader, BinaryWriter, which are waiting for some changes in master to propagate over to the feature branch.

* Address PR feedback
diff --git a/src/System.Private.CoreLib/shared/System/IO/DisableMediaInsertionPrompt.cs b/src/System.Private.CoreLib/shared/System/IO/DisableMediaInsertionPrompt.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 #if MS_IO_REDIST
 using System;
 
diff --git a/src/System.Private.CoreLib/shared/System/IO/DriveInfoInternal.Unix.cs b/src/System.Private.CoreLib/shared/System/IO/DriveInfoInternal.Unix.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Diagnostics;
 using System.Text;
 
diff --git a/src/System.Private.CoreLib/shared/System/IO/DriveInfoInternal.Windows.cs b/src/System.Private.CoreLib/shared/System/IO/DriveInfoInternal.Windows.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Diagnostics;
 using System.Text;
 
@@ -51,7 +52,7 @@ public static string NormalizeDriveName(string driveName)
         {
             Debug.Assert(driveName != null);
 
-            string name;
+            string? name;
 
             if (driveName.Length == 1)
             {
diff --git a/src/System.Private.CoreLib/shared/System/IO/EncodingCache.cs b/src/System.Private.CoreLib/shared/System/IO/EncodingCache.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Text;
 
 namespace System.IO
diff --git a/src/System.Private.CoreLib/shared/System/IO/Error.cs b/src/System.Private.CoreLib/shared/System/IO/Error.cs
@@ -2,11 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
-using System.Runtime.InteropServices;
-using System.Text;
-using System.Globalization;
-
+#nullable enable
 namespace System.IO
 {
     /// <summary>
diff --git a/src/System.Private.CoreLib/shared/System/IO/FileAccess.cs b/src/System.Private.CoreLib/shared/System/IO/FileAccess.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System;
 
 namespace System.IO
diff --git a/src/System.Private.CoreLib/shared/System/IO/FileMode.cs b/src/System.Private.CoreLib/shared/System/IO/FileMode.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 namespace System.IO
 {
     // Contains constants for specifying how the OS should open a file.
diff --git a/src/System.Private.CoreLib/shared/System/IO/FileOptions.cs b/src/System.Private.CoreLib/shared/System/IO/FileOptions.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System;
 using System.Runtime.InteropServices;
 
diff --git a/src/System.Private.CoreLib/shared/System/IO/FileShare.cs b/src/System.Private.CoreLib/shared/System/IO/FileShare.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System;
 
 namespace System.IO
diff --git a/src/System.Private.CoreLib/shared/System/IO/Path.Unix.cs b/src/System.Private.CoreLib/shared/System/IO/Path.Unix.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Diagnostics;
 using System.Runtime.InteropServices;
 using System.Text;
@@ -77,7 +78,7 @@ public static string GetTempPath()
             // Get the temp path from the TMPDIR environment variable.
             // If it's not set, just return the default path.
             // If it is, return it, ensuring it ends with a slash.
-            string path = Environment.GetEnvironmentVariable(TempEnvVar);
+            string? path = Environment.GetEnvironmentVariable(TempEnvVar);
             return
                 string.IsNullOrEmpty(path) ? DefaultTempPath :
                 PathInternal.IsDirectorySeparator(path[path.Length - 1]) ? path :
@@ -103,7 +104,7 @@ public static string GetTempFileName()
             return Encoding.UTF8.GetString(name, 0, name.Length - 1); // trim off the trailing '\0'
         }
 
-        public static bool IsPathRooted(string path)
+        public static bool IsPathRooted(string? path)
         {
             if (path == null)
                 return false;
@@ -119,7 +120,7 @@ public static bool IsPathRooted(ReadOnlySpan<char> path)
         /// <summary>
         /// Returns the path root or null if path is empty or null.
         /// </summary>
-        public static string GetPathRoot(string path)
+        public static string? GetPathRoot(string? path)
         {
             if (PathInternal.IsEffectivelyEmpty(path)) return null;
 
diff --git a/src/System.Private.CoreLib/shared/System/IO/Path.Windows.cs b/src/System.Private.CoreLib/shared/System/IO/Path.Windows.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Diagnostics;
 using System.Text;
 
@@ -83,7 +84,7 @@ public static string GetFullPath(string path, string basePath)
                 return basePath;
 
             int length = path.Length;
-            string combinedPath = null;
+            string? combinedPath = null;
 
             if ((length >= 1 && PathInternal.IsDirectorySeparator(path[0])))
             {
@@ -189,7 +190,7 @@ public static string GetTempFileName()
 
         // Tests if the given path contains a root. A path is considered rooted
         // if it starts with a backslash ("\") or a valid drive letter and a colon (":").
-        public static bool IsPathRooted(string path)
+        public static bool IsPathRooted(string? path)
         {
             return path != null && IsPathRooted(path.AsSpan());
         }
@@ -210,13 +211,13 @@ public static bool IsPathRooted(ReadOnlySpan<char> path)
         // and "\\server\share" (a UNC path for a given server and share name).
         // The resulting string is null if path is null. If the path is empty or
         // only contains whitespace characters an ArgumentException gets thrown.
-        public static string GetPathRoot(string path)
+        public static string? GetPathRoot(string? path)
         {
             if (PathInternal.IsEffectivelyEmpty(path.AsSpan()))
                 return null;
 
             ReadOnlySpan<char> result = GetPathRoot(path.AsSpan());
-            if (path.Length == result.Length)
+            if (path!.Length == result.Length)
                 return PathInternal.NormalizeDirectorySeparators(path);
 
             return PathInternal.NormalizeDirectorySeparators(result.ToString());
diff --git a/src/System.Private.CoreLib/shared/System/IO/Path.cs b/src/System.Private.CoreLib/shared/System/IO/Path.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Diagnostics;
 using System.Runtime.InteropServices;
 using System.Text;
@@ -45,7 +46,7 @@ public static partial class Path
         // returns null. If path does not contain a file extension,
         // the new file extension is appended to the path. If extension
         // is null, any existing extension is removed from path.
-        public static string ChangeExtension(string path, string extension)
+        public static string? ChangeExtension(string? path, string? extension) // TODO-NULLABLE: https://github.com/dotnet/roslyn/issues/26761
         {
             if (path == null)
                 return null;
@@ -98,7 +99,7 @@ public static string ChangeExtension(string path, string extension)
         /// <remarks>
         /// Directory separators are normalized in the returned string.
         /// </remarks>
-        public static string GetDirectoryName(string path)
+        public static string? GetDirectoryName(string? path) // TODO-NULLABLE: https://github.com/dotnet/roslyn/issues/26761
         {
             if (path == null || PathInternal.IsEffectivelyEmpty(path.AsSpan()))
                 return null;
@@ -146,7 +147,7 @@ private static int GetDirectoryNameOffset(ReadOnlySpan<char> path)
         /// The returned value is null if the given path is null or empty if the given path does not include an
         /// extension.
         /// </summary>
-        public static string GetExtension(string path)
+        public static string? GetExtension(string? path) // TODO-NULLABLE: https://github.com/dotnet/roslyn/issues/26761
         {
             if (path == null)
                 return null;
@@ -185,7 +186,7 @@ public static ReadOnlySpan<char> GetExtension(ReadOnlySpan<char> path)
         /// the characters of path that follow the last separator in path. The resulting string is
         /// null if path is null.
         /// </summary>
-        public static string GetFileName(string path)
+        public static string? GetFileName(string? path)
         {
             if (path == null)
                 return null;
@@ -216,7 +217,7 @@ public static ReadOnlySpan<char> GetFileName(ReadOnlySpan<char> path)
             return path;
         }
 
-        public static string GetFileNameWithoutExtension(string path)
+        public static string? GetFileNameWithoutExtension(string? path) // TODO-NULLABLE: https://github.com/dotnet/roslyn/issues/26761
         {
             if (path == null)
                 return null;
@@ -290,7 +291,7 @@ public static bool IsPathFullyQualified(ReadOnlySpan<char> path)
         /// Tests if a path's file name includes a file extension. A trailing period
         /// is not considered an extension.
         /// </summary>
-        public static bool HasExtension(string path)
+        public static bool HasExtension(string? path)
         {
             if (path != null)
             {
@@ -433,12 +434,12 @@ public static string Join(ReadOnlySpan<char> path1, ReadOnlySpan<char> path2, Re
             return JoinInternal(path1, path2, path3);
         }
 
-        public static string Join(string path1, string path2)
+        public static string Join(string? path1, string? path2)
         {
             return Join(path1.AsSpan(), path2.AsSpan());
         }
 
-        public static string Join(string path1, string path2, string path3)
+        public static string Join(string? path1, string? path2, string? path3)
         {
             return Join(path1.AsSpan(), path2.AsSpan(), path3.AsSpan());
         }
diff --git a/src/System.Private.CoreLib/shared/System/IO/PathHelper.Windows.cs b/src/System.Private.CoreLib/shared/System/IO/PathHelper.Windows.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Diagnostics;
 using System.Runtime.InteropServices;
 using System.Text;
@@ -126,7 +127,7 @@ internal static int PrependDevicePathChars(ref ValueStringBuilder content, bool
             }
         }
 
-        internal static string TryExpandShortFileName(ref ValueStringBuilder outputBuilder, string originalPath)
+        internal static string TryExpandShortFileName(ref ValueStringBuilder outputBuilder, string? originalPath)
         {
             // We guarantee we'll expand short names for paths that only partially exist. As such, we need to find the part of the path that actually does exist. To
             // avoid allocating like crazy we'll create only one input array and modify the contents with embedded nulls.
diff --git a/src/System.Private.CoreLib/shared/System/IO/PathInternal.Unix.cs b/src/System.Private.CoreLib/shared/System/IO/PathInternal.Unix.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Diagnostics;
 using System.Text;
 using System.Runtime.InteropServices;
@@ -89,7 +90,7 @@ internal static bool IsPartiallyQualified(ReadOnlySpan<char> path)
         /// For unix, this is empty or null. For Windows, this is empty, null, or 
         /// just spaces ((char)32).
         /// </summary>
-        internal static bool IsEffectivelyEmpty(string path)
+        internal static bool IsEffectivelyEmpty(string? path)
         {
             return string.IsNullOrEmpty(path);
         }
diff --git a/src/System.Private.CoreLib/shared/System/IO/PathInternal.Windows.cs b/src/System.Private.CoreLib/shared/System/IO/PathInternal.Windows.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Runtime.CompilerServices;
 using System.Text;
 
@@ -70,7 +71,7 @@ internal static bool IsValidDriveChar(char value)
             return ((value >= 'A' && value <= 'Z') || (value >= 'a' && value <= 'z'));
         }
 
-        internal static bool EndsWithPeriodOrSpace(string path)
+        internal static bool EndsWithPeriodOrSpace(string? path)
         {
             if (string.IsNullOrEmpty(path))
                 return false;
@@ -86,7 +87,7 @@ internal static bool EndsWithPeriodOrSpace(string path)
         /// away from paths during normalization, but if we see such a path at this point it should be
         /// normalized and has retained the final characters. (Typically from one of the *Info classes)
         /// </summary>
-        internal static string EnsureExtendedPrefixIfNeeded(string path)
+        internal static string? EnsureExtendedPrefixIfNeeded(string? path)
         {
             if (path != null && (path.Length >= MaxShortPath || EndsWithPeriodOrSpace(path)))
             {
@@ -103,7 +104,7 @@ internal static string EnsureExtendedPrefixIfNeeded(string path)
         /// Adds the extended path prefix (\\?\) if not already a device path, IF the path is not relative,
         /// AND the path is more than 259 characters. (> MAX_PATH + null)
         /// </summary>
-        internal static string EnsureExtendedPrefixOverMaxPath(string path)
+        internal static string? EnsureExtendedPrefixOverMaxPath(string? path)
         {
             if (path != null && path.Length >= MaxShortPath)
             {
diff --git a/src/System.Private.CoreLib/shared/System/IO/PathInternal.cs b/src/System.Private.CoreLib/shared/System/IO/PathInternal.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Diagnostics;
 using System.Text;
 
diff --git a/src/System.Private.CoreLib/shared/System/IO/PersistedFiles.Names.Unix.cs b/src/System.Private.CoreLib/shared/System/IO/PersistedFiles.Names.Unix.cs
@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 namespace System.IO
 {
     internal static partial class PersistedFiles
diff --git a/src/System.Private.CoreLib/shared/System/IO/PersistedFiles.Unix.cs b/src/System.Private.CoreLib/shared/System/IO/PersistedFiles.Unix.cs
@@ -2,14 +2,15 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+#nullable enable
 using System.Diagnostics;
 using System.Runtime.InteropServices;
 
 namespace System.IO
 {
     internal static partial class PersistedFiles
     {
-        private static string s_userProductDirectory;
+        private static string? s_userProductDirectory;
 
         /// <summary>
         /// Get the location of where to persist information for a particular aspect of the framework,
@@ -24,7 +25,7 @@ internal static string GetUserFeatureDirectory(string featureName)
                 EnsureUserDirectories();
             }
 
-            return Path.Combine(s_userProductDirectory, featureName);
+            return Path.Combine(s_userProductDirectory!, featureName);
         }
 
         /// <summary>
@@ -41,7 +42,7 @@ internal static string GetUserFeatureDirectory(string featureName, string subFea
                 EnsureUserDirectories();
             }
 
-            return Path.Combine(s_userProductDirectory, featureName, subFeatureName);
+            return Path.Combine(s_userProductDirectory!, featureName, subFeatureName);
         }
 
         /// <summary>
@@ -60,12 +61,12 @@ internal static string GetUserFeatureDirectory(params string[] featurePathParts)
                 EnsureUserDirectories();
             }
 
-            return Path.Combine(s_userProductDirectory, Path.Combine(featurePathParts));
+            return Path.Combine(s_userProductDirectory!, Path.Combine(featurePathParts));
         }
 
         private static void EnsureUserDirectories()
         {
-            string userHomeDirectory = GetHomeDirectory();
+            string? userHomeDirectory = GetHomeDirectory();
 
             if (string.IsNullOrEmpty(userHomeDirectory))
             {
@@ -80,11 +81,11 @@ private static void EnsureUserDirectories()
 
         /// <summary>Gets the current user's home directory.</summary>
         /// <returns>The path to the home directory, or null if it could not be determined.</returns>
-        internal static string GetHomeDirectory()
+        internal static string? GetHomeDirectory()
         {
             // First try to get the user's home directory from the HOME environment variable.
             // This should work in most cases.
-            string userHomeDirectory = Environment.GetEnvironmentVariable("HOME");
+            string? userHomeDirectory = Environment.GetEnvironmentVariable("HOME");
             if (!string.IsNullOrEmpty(userHomeDirectory))
                 return userHomeDirectory;
 
@@ -123,7 +124,7 @@ internal static string GetHomeDirectory()
         /// <param name="bufLen">The length of <paramref name="buf"/>.</param>
         /// <param name="path">The resulting path; null if the user didn't have an entry.</param>
         /// <returns>true if the call was successful (path may still be null); false is a larger buffer is needed.</returns>
-        private static unsafe bool TryGetHomeDirectoryFromPasswd(byte* buf, int bufLen, out string path)
+        private static unsafe bool TryGetHomeDirectoryFromPasswd(byte* buf, int bufLen, out string? path)
         {
             // Call getpwuid_r to get the passwd struct
             Interop.Sys.Passwd passwd;
diff --git a/src/System.Private.CoreLib/shared/System/IO/SeekOrigin.cs b/src/System.Private.CoreLib/shared/System/IO/SeekOrigin.cs
diff --git a/src/System.Private.CoreLib/shared/System/IO/TextReader.cs b/src/System.Private.CoreLib/shared/System/IO/TextReader.cs
diff --git a/src/System.Private.CoreLib/shared/System/IO/TextWriter.cs b/src/System.Private.CoreLib/shared/System/IO/TextWriter.cs
diff --git a/src/System.Private.CoreLib/shared/System/IO/UnmanagedMemoryAccessor.cs b/src/System.Private.CoreLib/shared/System/IO/UnmanagedMemoryAccessor.cs
diff --git a/src/System.Private.CoreLib/shared/System/ParamsArray.cs b/src/System.Private.CoreLib/shared/System/ParamsArray.cs
diff --git a/src/System.Private.CoreLib/shared/System/Text/StringBuilder.cs b/src/System.Private.CoreLib/shared/System/Text/StringBuilder.cs

Original file line number	Diff line number	Diff line change
`@@ -2,6 +2,7 @@`
`2`	`2`	`// The .NET Foundation licenses this file to you under the MIT license.`
`3`	`3`	`// See the LICENSE file in the project root for more information.`
`4`	`4`
	`5`	`+#nullable enable`
`5`	`6`	`using System.Diagnostics;`
`6`	`7`	`using System.Text;`
`7`	`8`
`@@ -51,7 +52,7 @@ public static string NormalizeDriveName(string driveName)`
`51`	`52`	`{`
`52`	`53`	`Debug.Assert(driveName != null);`
`53`	`54`
`54`		`- string name;`
	`55`	`+ string? name;`
`55`	`56`
`56`	`57`	`if (driveName.Length == 1)`
`57`	`58`	`{`