Implement Shuffle, GetString, and GetItems on Random{NumberGenerator} (…

…#78598) * Implement Shuffle, GetString, and GetItems. * Cleanup and additional tests * Use where possible * Code review feedback * Additional uses of Random throughout tests * Feedback on documentation * Use ref to span to get span in string.Create. Co-authored-by: Benjamin Moir <[email protected]> Co-authored-by: Theodore Tsirpanis <[email protected]> Co-authored-by: Michał Petryka <[email protected]> * Code review feedback * Code review feedback * Apply suggestions from code review Co-authored-by: Dan Moseley <[email protected]> * Use AssertExtensions over Assert * Improve comment * No idea where AssertHexString came from * Update src/libraries/System.Security.Cryptography/src/System/Security/Cryptography/RandomNumberGenerator.cs Co-authored-by: Jeremy Barton <[email protected]> Co-authored-by: Benjamin Moir <[email protected]> Co-authored-by: Theodore Tsirpanis <[email protected]> Co-authored-by: Michał Petryka <[email protected]> Co-authored-by: Dan Moseley <[email protected]> Co-authored-by: Stephen Toub <[email protected]> Co-authored-by: Jeremy Barton <[email protected]>
dotnet · Jan 12, 2023 · 05e1fe1 · 05e1fe1
1 parent 210a7a9
commit 05e1fe1
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Showing 21 changed files with 840 additions and 136 deletions.
diff --git a/src/libraries/Common/tests/System/RandomExtensions.cs b/src/libraries/Common/tests/System/RandomExtensions.cs
diff --git a/src/libraries/Common/tests/Tests/System/StringTests.cs b/src/libraries/Common/tests/Tests/System/StringTests.cs
@@ -3776,12 +3776,7 @@ public static void IsWhiteSpaceTrueLatin1()
             Random rand = new Random(42);
             for (int length = 0; length < 32; length++)
             {
-                char[] a = new char[length];
-                for (int i = 0; i < length; i++)
-                {
-                    a[i] = s_whiteSpaceCharacters[rand.Next(0, s_whiteSpaceCharacters.Length - 1)];
-                }
-
+                char[] a = rand.GetItems<char>(s_whiteSpaceCharacters, length);
                 string s1 = new string(a);
                 bool result = string.IsNullOrWhiteSpace(s1);
                 Assert.True(result);
@@ -3810,11 +3805,7 @@ public static void IsWhiteSpaceTrue()
             Random rand = new Random(42);
             for (int length = 0; length < 32; length++)
             {
-                char[] a = new char[length];
-                for (int i = 0; i < length; i++)
-                {
-                    a[i] = s_whiteSpaceCharacters[rand.Next(0, s_whiteSpaceCharacters.Length)];
-                }
+                char[] a = rand.GetItems<char>(s_whiteSpaceCharacters, length);
 
                 string s1 = new string(a);
                 bool result = string.IsNullOrWhiteSpace(s1);
@@ -3832,11 +3823,7 @@ public static void IsWhiteSpaceFalse()
             Random rand = new Random(42);
             for (int length = 1; length < 32; length++)
             {
-                char[] a = new char[length];
-                for (int i = 0; i < length; i++)
-                {
-                    a[i] = s_whiteSpaceCharacters[rand.Next(0, s_whiteSpaceCharacters.Length)];
-                }
+                char[] a = rand.GetItems<char>(s_whiteSpaceCharacters, length);
                 var span = new Span<char>(a);
 
                 // first character is not a white-space character

diff --git a/src/libraries/System.Collections/tests/Generic/Dictionary/Dictionary.Generic.Tests.cs b/src/libraries/System.Collections/tests/Generic/Dictionary/Dictionary.Generic.Tests.cs
@@ -1,7 +1,6 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-using Common.System;
 using System.Collections.Generic;
 using System.Globalization;
 using System.Linq;

diff --git a/src/libraries/System.Collections/tests/System.Collections.Tests.csproj b/src/libraries/System.Collections/tests/System.Collections.Tests.csproj
@@ -45,8 +45,6 @@
              Link="Common\System\EnumTypes.cs" />
     <Compile Include="$(CommonTestPath)System\ObjectCloner.cs"
              Link="Common\System\ObjectCloner.cs" />
-    <Compile Include="$(CommonTestPath)System\RandomExtensions.cs"
-             Link="Common\System\RandomExtensions.cs" />
     <Compile Include="$(CommonTestPath)System\Runtime\Serialization\Formatters\BinaryFormatterHelpers.cs"
              Link="Common\System\Runtime\Serialization\Formatters\BinaryFormatterHelpers.cs" />
     <!-- Generic tests -->

diff --git a/...ries/System.DirectoryServices/src/System/DirectoryServices/ActiveDirectory/TrustHelper.cs b/...ries/System.DirectoryServices/src/System/DirectoryServices/ActiveDirectory/TrustHelper.cs
@@ -947,14 +947,8 @@ private static void ValidateTrustAttribute(TRUSTED_DOMAIN_INFORMATION_EX domainI
 
         internal static string CreateTrustPassword()
         {
-#if NETCOREAPP3_0_OR_GREATER
-            return string.Create<object?>(PASSWORD_LENGTH, null, static (destination, _) =>
-            {
-                for (int i = 0; i < destination.Length; i++)
-                {
-                    destination[i] = PasswordCharacterSet[RandomNumberGenerator.GetInt32(PasswordCharacterSet.Length)];
-                }
-            });
+#if NET8_0_OR_GREATER
+            return RandomNumberGenerator.GetString(PasswordCharacterSet, PASSWORD_LENGTH);
 #else
             char[] cBuf = new char[PASSWORD_LENGTH];
             byte[] randomBuffer = new byte[1];

diff --git a/src/libraries/System.IO/tests/StreamReader/StreamReaderTests.cs b/src/libraries/System.IO/tests/StreamReader/StreamReaderTests.cs
@@ -15,6 +15,8 @@ namespace System.IO.Tests
 {
     public partial class StreamReaderTests
     {
+        private const string LowerAlpha = "abcdefghijklmnopqrstuvwxyz";
+
         protected virtual Stream CreateStream()
         {
             return new MemoryStream();
@@ -400,12 +402,8 @@ public async Task Read_EmptySpan_ReadsNothing(int length)
         [InlineData(100, 50, 101)]
         public void Read_ReadsExpectedData(int readLength, int totalLength, int bufferSize)
         {
-            var data = new char[totalLength];
             var r = new Random(42);
-            for (int i = 0; i < data.Length; i++)
-            {
-                data[i] = (char)('a' + r.Next(0, 26));
-            }
+            char[] data = r.GetItems<char>(LowerAlpha, totalLength);
 
             var result = new char[data.Length];
             Span<char> dst = result;
@@ -431,12 +429,8 @@ public void Read_ReadsExpectedData(int readLength, int totalLength, int bufferSi
         [InlineData(100, 50, 101)]
         public void ReadBlock_ReadsExpectedData(int readLength, int totalLength, int bufferSize)
         {
-            var data = new char[totalLength];
             var r = new Random(42);
-            for (int i = 0; i < data.Length; i++)
-            {
-                data[i] = (char)('a' + r.Next(0, 26));
-            }
+            char[] data = r.GetItems<char>(LowerAlpha, totalLength);
 
             var result = new char[data.Length];
             Span<char> dst = result;
@@ -462,12 +456,8 @@ public void ReadBlock_ReadsExpectedData(int readLength, int totalLength, int buf
         [InlineData(100, 50, 101)]
         public async Task ReadAsync_ReadsExpectedData(int readLength, int totalLength, int bufferSize)
         {
-            var data = new char[totalLength];
             var r = new Random(42);
-            for (int i = 0; i < data.Length; i++)
-            {
-                data[i] = (char)('a' + r.Next(0, 26));
-            }
+            char[] data = r.GetItems<char>(LowerAlpha, totalLength);
 
             var result = new char[data.Length];
             Memory<char> dst = result;
@@ -493,12 +483,9 @@ public async Task ReadAsync_ReadsExpectedData(int readLength, int totalLength, i
         [InlineData(100, 50, 101)]
         public async Task ReadBlockAsync_ReadsExpectedData(int readLength, int totalLength, int bufferSize)
         {
-            var data = new char[totalLength];
             var r = new Random(42);
-            for (int i = 0; i < data.Length; i++)
-            {
-                data[i] = (char)('a' + r.Next(0, 26));
-            }
+            char[] data = r.GetItems<char>(LowerAlpha, totalLength);
+
 
             var result = new char[data.Length];
             Memory<char> dst = result;

diff --git a/src/libraries/System.IO/tests/StreamWriter/StreamWriter.WriteTests.cs b/src/libraries/System.IO/tests/StreamWriter/StreamWriter.WriteTests.cs
@@ -12,6 +12,8 @@ namespace System.IO.Tests
 {
     public partial class WriteTests
     {
+        private const string LowerAlpha = "abcdefghijklmnopqrstuvwxyz";
+
         protected virtual Stream CreateStream()
         {
             return new MemoryStream();
@@ -250,12 +252,8 @@ public void Write_Span_WritesExpectedData(int length, int writeSize, int writerB
             using (var s = new MemoryStream())
             using (var writer = new StreamWriter(s, Encoding.ASCII, writerBufferSize) { AutoFlush = autoFlush })
             {
-                var data = new char[length];
                 var rand = new Random(42);
-                for (int i = 0; i < data.Length; i++)
-                {
-                    data[i] = (char)(rand.Next(0, 26) + 'a');
-                }
+                char[] data = rand.GetItems<char>(LowerAlpha, length);
 
                 Span<char> source = data;
                 while (source.Length > 0)
@@ -283,12 +281,8 @@ public async Task Write_Memory_WritesExpectedData(int length, int writeSize, int
             using (var s = new MemoryStream())
             using (var writer = new StreamWriter(s, Encoding.ASCII, writerBufferSize) { AutoFlush = autoFlush })
             {
-                var data = new char[length];
                 var rand = new Random(42);
-                for (int i = 0; i < data.Length; i++)
-                {
-                    data[i] = (char)(rand.Next(0, 26) + 'a');
-                }
+                char[] data = rand.GetItems<char>(LowerAlpha, length);
 
                 ReadOnlyMemory<char> source = data;
                 while (source.Length > 0)
@@ -316,12 +310,8 @@ public void WriteLine_Span_WritesExpectedData(int length, int writeSize, int wri
             using (var s = new MemoryStream())
             using (var writer = new StreamWriter(s, Encoding.ASCII, writerBufferSize) { AutoFlush = autoFlush })
             {
-                var data = new char[length];
                 var rand = new Random(42);
-                for (int i = 0; i < data.Length; i++)
-                {
-                    data[i] = (char)(rand.Next(0, 26) + 'a');
-                }
+                char[] data = rand.GetItems<char>(LowerAlpha, length);
 
                 Span<char> source = data;
                 while (source.Length > 0)
@@ -349,12 +339,8 @@ public async Task WriteLineAsync_Memory_WritesExpectedData(int length, int write
             using (var s = new MemoryStream())
             using (var writer = new StreamWriter(s, Encoding.ASCII, writerBufferSize) { AutoFlush = autoFlush })
             {
-                var data = new char[length];
                 var rand = new Random(42);
-                for (int i = 0; i < data.Length; i++)
-                {
-                    data[i] = (char)(rand.Next(0, 26) + 'a');
-                }
+                char[] data = rand.GetItems<char>(LowerAlpha, length);
 
                 ReadOnlyMemory<char> source = data;
                 while (source.Length > 0)

diff --git a/src/libraries/System.Linq/tests/Shuffler.cs b/src/libraries/System.Linq/tests/Shuffler.cs
@@ -11,12 +11,7 @@ public static class Shuffler
         public static T[] Shuffle<T>(T[] array)
         {
             var r = new Random(42);
-            int i = array.Length;
-            while (i > 1)
-            {
-                int j = r.Next(i--);
-                (array[i], array[j]) = (array[j], array[i]);
-            }
+            r.Shuffle(array);
             return array;
         }
 

diff --git a/...ies/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/AuthenticationHelper.Digest.cs b/...ies/System.Net.Http/src/System/Net/Http/SocketsHttpHandler/AuthenticationHelper.Digest.cs
@@ -207,14 +207,7 @@ private static string GetRandomAlphaNumericString()
         {
             const int Length = 16;
             const string CharacterSet = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
-
-            return string.Create<object?>(Length, null, static (destination, _) =>
-            {
-                for (int i = 0; i < destination.Length; i++)
-                {
-                    destination[i] = CharacterSet[RandomNumberGenerator.GetInt32(CharacterSet.Length)];
-                }
-            });
+            return RandomNumberGenerator.GetString(CharacterSet, Length);
         }
 
         private static string ComputeHash(string data, string algorithm)

diff --git a/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientHandlerTest.Headers.cs b/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientHandlerTest.Headers.cs
@@ -215,7 +215,7 @@ await LoopbackServerFactory.CreateClientAndServerAsync(async uri =>
         public async Task GetAsync_LargeHeader_Success(string headerName, int headerValueLength)
         {
             var rand = new Random(42);
-            string headerValue = string.Concat(Enumerable.Range(0, headerValueLength).Select(_ => (char)('A' + rand.Next(26))));
+            string headerValue = new string(rand.GetItems<char>("ABCDEFGHIJKLMNOPQRSTUVWXYZ", headerValueLength));
 
             const string ContentString = "hello world";
             await LoopbackServerFactory.CreateClientAndServerAsync(async uri =>

diff --git a/src/libraries/System.Net.HttpListener/tests/HttpRequestStreamTests.cs b/src/libraries/System.Net.HttpListener/tests/HttpRequestStreamTests.cs
@@ -229,10 +229,7 @@ public async Task Read_FullLengthSynchronous_Success(bool transferEncodingChunke
         public async Task Read_LargeLengthAsynchronous_Success(bool transferEncodingChunked)
         {
             var rand = new Random(42);
-            byte[] expected = Enumerable
-                .Range(0, 128*1024 + 1) // More than 128kb
-                .Select(_ => (byte)('a' + rand.Next(0, 26)))
-                .ToArray();
+            byte[] expected = rand.GetItems("abcdefghijklmnopqrstuvwxyz"u8, 128 * 1024 + 1);
 
             Task<HttpListenerContext> contextTask = _listener.GetContextAsync();
 
@@ -269,10 +266,7 @@ public async Task Read_LargeLengthAsynchronous_Success(bool transferEncodingChun
         public async Task Read_LargeLengthSynchronous_Success(bool transferEncodingChunked)
         {
             var rand = new Random(42);
-            byte[] expected = Enumerable
-                .Range(0, 128 * 1024 + 1) // More than 128kb
-                .Select(_ => (byte)('a' + rand.Next(0, 26)))
-                .ToArray();
+            byte[] expected = rand.GetItems("abcdefghijklmnopqrstuvwxyz"u8, 128 * 1024 + 1);
 
             Task<HttpListenerContext> contextTask = _listener.GetContextAsync();
 

diff --git a/src/libraries/System.Net.WebClient/tests/WebClientTest.cs b/src/libraries/System.Net.WebClient/tests/WebClientTest.cs
@@ -661,7 +661,7 @@ public async Task UploadData_LargeData_Success(Uri server)
         }
 
         private static string GetRandomText(int length) =>
-            new string(Enumerable.Range(0, 512 * 1024).Select(_ => (char)('a' + Random.Shared.Next(0, 26))).ToArray());
+            new string(Random.Shared.GetItems<char>("abcdefghijklmnopqrstuvwxyz", 512 * 1024));
 
         [OuterLoop("Uses external servers")]
         [Theory]

diff --git a/src/libraries/System.Private.CoreLib/src/Resources/Strings.resx b/src/libraries/System.Private.CoreLib/src/Resources/Strings.resx
@@ -298,6 +298,9 @@
   <data name="Arg_EmptyArray" xml:space="preserve">
     <value>Array may not be empty.</value>
   </data>
+  <data name="Arg_EmptySpan" xml:space="preserve">
+    <value>Span may not be empty.</value>
+  </data>
   <data name="Arg_EndOfStreamException" xml:space="preserve">
     <value>Attempted to read past the end of the stream.</value>
   </data>