Consistently use inline stackallocs with ValueStringBuilder (#37795)

stephentoub · web-flow · commit cd02b0612b3c · 2020-06-12T16:49:10.000-04:00
Primarily for style consistency.
diff --git a/src/libraries/Common/tests/Tests/System/Text/ValueStringBuilderTests.cs b/src/libraries/Common/tests/Tests/System/Text/ValueStringBuilderTests.cs
@@ -283,8 +283,7 @@ public void EnsureCapacity_IfRequestedCapacityWins()
         {
             // Note: constants used here may be dependent on minimal buffer size
             // the ArrayPool is able to return.
-            Span<char> initialBuffer = stackalloc char[32];
-            var builder = new ValueStringBuilder(initialBuffer);
+            var builder = new ValueStringBuilder(stackalloc char[32]);
 
             builder.EnsureCapacity(65);
 
@@ -294,8 +293,7 @@ public void EnsureCapacity_IfRequestedCapacityWins()
         [Fact]
         public void EnsureCapacity_IfBufferTimesTwoWins()
         {
-            Span<char> initialBuffer = stackalloc char[32];
-            var builder = new ValueStringBuilder(initialBuffer);
+            var builder = new ValueStringBuilder(stackalloc char[32]);
 
             builder.EnsureCapacity(33);
 
@@ -307,8 +305,7 @@ public void EnsureCapacity_NoAllocIfNotNeeded()
         {
             // Note: constants used here may be dependent on minimal buffer size
             // the ArrayPool is able to return.
-            Span<char> initialBuffer = stackalloc char[64];
-            var builder = new ValueStringBuilder(initialBuffer);
+            var builder = new ValueStringBuilder(stackalloc char[64]);
 
             builder.EnsureCapacity(16);
 
diff --git a/src/libraries/System.Console/src/System/ConsolePal.Windows.cs b/src/libraries/System.Console/src/System/ConsolePal.Windows.cs
@@ -580,8 +580,7 @@ public static unsafe string Title
         {
             get
             {
-                Span<char> initialBuffer = stackalloc char[256];
-                ValueStringBuilder builder = new ValueStringBuilder(initialBuffer);
+                ValueStringBuilder builder = new ValueStringBuilder(stackalloc char[256]);
 
                 while (true)
                 {
diff --git a/src/libraries/System.IO.FileSystem/src/System/IO/Enumeration/FileSystemName.cs b/src/libraries/System.IO.FileSystem/src/System/IO/Enumeration/FileSystemName.cs
@@ -38,8 +38,7 @@ public static string TranslateWin32Expression(string? expression)
                 return "*";
 
             bool modified = false;
-            Span<char> stackSpace = stackalloc char[32];
-            ValueStringBuilder sb = new ValueStringBuilder(stackSpace);
+            ValueStringBuilder sb = new ValueStringBuilder(stackalloc char[32]);
             int length = expression.Length;
             for (int i = 0; i < length; i++)
             {
diff --git a/src/libraries/System.Private.CoreLib/src/System/ApplicationId.cs b/src/libraries/System.Private.CoreLib/src/System/ApplicationId.cs
@@ -38,8 +38,7 @@ public ApplicationId(byte[] publicKeyToken, string name, Version version, string
 
         public override string ToString()
         {
-            Span<char> charSpan = stackalloc char[128];
-            var sb = new ValueStringBuilder(charSpan);
+            var sb = new ValueStringBuilder(stackalloc char[128]);
             sb.Append(Name);
             if (Culture != null)
             {
diff --git a/src/libraries/System.Private.CoreLib/src/System/Net/WebUtility.cs b/src/libraries/System.Private.CoreLib/src/System/Net/WebUtility.cs
@@ -52,11 +52,8 @@ public static class WebUtility
             // characters need to be encoded.
             // For larger string we rent the input string's length plus a fixed
             // conservative amount of chars from the ArrayPool.
-            Span<char> buffer = value.Length < 80 ?
-                stackalloc char[256] :
-                null;
-            ValueStringBuilder sb = buffer != null ?
-                new ValueStringBuilder(buffer) :
+            ValueStringBuilder sb = value.Length < 80 ?
+                new ValueStringBuilder(stackalloc char[256]) :
                 new ValueStringBuilder(value.Length + 200);
 
             sb.Append(valueSpan.Slice(0, index));
@@ -92,11 +89,8 @@ public static void HtmlEncode(string? value, TextWriter output)
             // characters need to be encoded.
             // For larger string we rent the input string's length plus a fixed
             // conservative amount of chars from the ArrayPool.
-            Span<char> buffer = value.Length < 80 ?
-                stackalloc char[256] :
-                null;
-            ValueStringBuilder sb = buffer != null ?
-                new ValueStringBuilder(buffer) :
+            ValueStringBuilder sb = value.Length < 80 ?
+                new ValueStringBuilder(stackalloc char[256]) :
                 new ValueStringBuilder(value.Length + 200);
 
             sb.Append(valueSpan.Slice(0, index));
@@ -201,11 +195,8 @@ private static void HtmlEncode(ReadOnlySpan<char> input, ref ValueStringBuilder
 
             // In the worst case the decoded string has the same length.
             // For small inputs we use stack allocation.
-            Span<char> buffer = value.Length <= 256 ?
-                stackalloc char[256] :
-                null;
-            ValueStringBuilder sb = buffer != null ?
-                new ValueStringBuilder(buffer) :
+            ValueStringBuilder sb = value.Length <= 256 ?
+                new ValueStringBuilder(stackalloc char[256]) :
                 new ValueStringBuilder(value.Length);
 
             sb.Append(valueSpan.Slice(0, index));
@@ -238,11 +229,8 @@ public static void HtmlDecode(string? value, TextWriter output)
 
             // In the worst case the decoded string has the same length.
             // For small inputs we use stack allocation.
-            Span<char> buffer = value.Length <= 256 ?
-                stackalloc char[256] :
-                null;
-            ValueStringBuilder sb = buffer != null ?
-                new ValueStringBuilder(buffer) :
+            ValueStringBuilder sb = value.Length <= 256 ?
+                new ValueStringBuilder(stackalloc char[256]) :
                 new ValueStringBuilder(value.Length);
 
             sb.Append(valueSpan.Slice(0, index));
diff --git a/src/libraries/System.Private.CoreLib/src/System/Number.Formatting.cs b/src/libraries/System.Private.CoreLib/src/System/Number.Formatting.cs
@@ -378,15 +378,13 @@ internal static unsafe void DecimalToNumber(ref decimal d, ref NumberBuffer numb
 
         public static string FormatDouble(double value, string? format, NumberFormatInfo info)
         {
-            Span<char> stackBuffer = stackalloc char[CharStackBufferSize];
-            var sb = new ValueStringBuilder(stackBuffer);
+            var sb = new ValueStringBuilder(stackalloc char[CharStackBufferSize]);
             return FormatDouble(ref sb, value, format, info) ?? sb.ToString();
         }
 
         public static bool TryFormatDouble(double value, ReadOnlySpan<char> format, NumberFormatInfo info, Span<char> destination, out int charsWritten)
         {
-            Span<char> stackBuffer = stackalloc char[CharStackBufferSize];
-            var sb = new ValueStringBuilder(stackBuffer);
+            var sb = new ValueStringBuilder(stackalloc char[CharStackBufferSize]);
             string? s = FormatDouble(ref sb, value, format, info);
             return s != null ?
                 TryCopyTo(s, destination, out charsWritten) :
@@ -586,15 +584,13 @@ private static int GetFloatingPointMaxDigitsAndPrecision(char fmt, ref int preci
 
         public static string FormatSingle(float value, string? format, NumberFormatInfo info)
         {
-            Span<char> stackBuffer = stackalloc char[CharStackBufferSize];
-            var sb = new ValueStringBuilder(stackBuffer);
+            var sb = new ValueStringBuilder(stackalloc char[CharStackBufferSize]);
             return FormatSingle(ref sb, value, format, info) ?? sb.ToString();
         }
 
         public static bool TryFormatSingle(float value, ReadOnlySpan<char> format, NumberFormatInfo info, Span<char> destination, out int charsWritten)
         {
-            Span<char> stackBuffer = stackalloc char[CharStackBufferSize];
-            var sb = new ValueStringBuilder(stackBuffer);
+            var sb = new ValueStringBuilder(stackalloc char[CharStackBufferSize]);
             string? s = FormatSingle(ref sb, value, format, info);
             return s != null ?
                 TryCopyTo(s, destination, out charsWritten) :
diff --git a/src/libraries/System.Runtime.Numerics/src/System/Numerics/BigNumber.cs b/src/libraries/System.Runtime.Numerics/src/System/Numerics/BigNumber.cs
@@ -519,8 +519,7 @@ internal static char ParseFormatSpecifier(ReadOnlySpan<char> format, out int dig
             }
             bits = bits.Slice(0, bytesWrittenOrNeeded);
 
-            Span<char> stackSpace = stackalloc char[128]; // each byte is typically two chars
-            var sb = new ValueStringBuilder(stackSpace);
+            var sb = new ValueStringBuilder(stackalloc char[128]); // each byte is typically two chars
 
             int cur = bits.Length - 1;
             if (cur > -1)
@@ -729,8 +728,7 @@ internal static bool TryFormatBigInteger(BigInteger value, ReadOnlySpan<char> fo
                 int precision = 29;
                 int scale = cchMax - ichDst;
 
-                Span<char> stackSpace = stackalloc char[128]; // arbitrary stack cut-off
-                var sb = new ValueStringBuilder(stackSpace);
+                var sb = new ValueStringBuilder(stackalloc char[128]); // arbitrary stack cut-off
                 FormatProvider.FormatBigInteger(ref sb, precision, scale, sign, formatSpan, info, rgch, ichDst);
 
                 if (targetSpan)
diff --git a/src/libraries/System.ServiceProcess.ServiceController/src/System/ServiceProcess/ServiceController.cs b/src/libraries/System.ServiceProcess.ServiceController/src/System/ServiceProcess/ServiceController.cs
@@ -538,8 +538,7 @@ private unsafe void GenerateNames()
         /// </summary>
         private unsafe string? GetServiceKeyName(SafeServiceHandle? SCMHandle, string serviceDisplayName)
         {
-            Span<char> initialBuffer = stackalloc char[256];
-            var builder = new ValueStringBuilder(initialBuffer);
+            var builder = new ValueStringBuilder(stackalloc char[256]);
             int bufLen;
             while (true)
             {

Original file line number	Diff line number	Diff line change
`@@ -580,8 +580,7 @@ public static unsafe string Title`
`580`	`580`	`{`
`581`	`581`	`get`
`582`	`582`	`{`
`583`		`- Span<char> initialBuffer = stackalloc char[256];`
`584`		`- ValueStringBuilder builder = new ValueStringBuilder(initialBuffer);`
	`583`	`+ ValueStringBuilder builder = new ValueStringBuilder(stackalloc char[256]);`
`585`	`584`
`586`	`585`	`while (true)`
`587`	`586`	`{`
Original file line number	Diff line number	Diff line change
`@@ -38,8 +38,7 @@ public static string TranslateWin32Expression(string? expression)`
`38`	`38`	`return "*";`
`39`	`39`
`40`	`40`	`bool modified = false;`
`41`		`- Span<char> stackSpace = stackalloc char[32];`
`42`		`- ValueStringBuilder sb = new ValueStringBuilder(stackSpace);`
	`41`	`+ ValueStringBuilder sb = new ValueStringBuilder(stackalloc char[32]);`
`43`	`42`	`int length = expression.Length;`
`44`	`43`	`for (int i = 0; i < length; i++)`
`45`	`44`	`{`
Original file line number	Diff line number	Diff line change
`@@ -38,8 +38,7 @@ public ApplicationId(byte[] publicKeyToken, string name, Version version, string`
`38`	`38`
`39`	`39`	`public override string ToString()`
`40`	`40`	`{`
`41`		`- Span<char> charSpan = stackalloc char[128];`
`42`		`- var sb = new ValueStringBuilder(charSpan);`
	`41`	`+ var sb = new ValueStringBuilder(stackalloc char[128]);`
`43`	`42`	`sb.Append(Name);`
`44`	`43`	`if (Culture != null)`
`45`	`44`	`{`
Original file line number	Diff line number	Diff line change
`@@ -378,15 +378,13 @@ internal static unsafe void DecimalToNumber(ref decimal d, ref NumberBuffer numb`
`378`	`378`
`379`	`379`	`public static string FormatDouble(double value, string? format, NumberFormatInfo info)`
`380`	`380`	`{`
`381`		`- Span<char> stackBuffer = stackalloc char[CharStackBufferSize];`
`382`		`- var sb = new ValueStringBuilder(stackBuffer);`
	`381`	`+ var sb = new ValueStringBuilder(stackalloc char[CharStackBufferSize]);`
`383`	`382`	`return FormatDouble(ref sb, value, format, info) ?? sb.ToString();`
`384`	`383`	`}`
`385`	`384`
`386`	`385`	`public static bool TryFormatDouble(double value, ReadOnlySpan<char> format, NumberFormatInfo info, Span<char> destination, out int charsWritten)`
`387`	`386`	`{`
`388`		`- Span<char> stackBuffer = stackalloc char[CharStackBufferSize];`
`389`		`- var sb = new ValueStringBuilder(stackBuffer);`
	`387`	`+ var sb = new ValueStringBuilder(stackalloc char[CharStackBufferSize]);`
`390`	`388`	`string? s = FormatDouble(ref sb, value, format, info);`
`391`	`389`	`return s != null ?`
`392`	`390`	`TryCopyTo(s, destination, out charsWritten) :`
`@@ -586,15 +584,13 @@ private static int GetFloatingPointMaxDigitsAndPrecision(char fmt, ref int preci`
`586`	`584`
`587`	`585`	`public static string FormatSingle(float value, string? format, NumberFormatInfo info)`
`588`	`586`	`{`
`589`		`- Span<char> stackBuffer = stackalloc char[CharStackBufferSize];`
`590`		`- var sb = new ValueStringBuilder(stackBuffer);`
	`587`	`+ var sb = new ValueStringBuilder(stackalloc char[CharStackBufferSize]);`
`591`	`588`	`return FormatSingle(ref sb, value, format, info) ?? sb.ToString();`
`592`	`589`	`}`
`593`	`590`
`594`	`591`	`public static bool TryFormatSingle(float value, ReadOnlySpan<char> format, NumberFormatInfo info, Span<char> destination, out int charsWritten)`
`595`	`592`	`{`
`596`		`- Span<char> stackBuffer = stackalloc char[CharStackBufferSize];`
`597`		`- var sb = new ValueStringBuilder(stackBuffer);`
	`593`	`+ var sb = new ValueStringBuilder(stackalloc char[CharStackBufferSize]);`
`598`	`594`	`string? s = FormatSingle(ref sb, value, format, info);`
`599`	`595`	`return s != null ?`
`600`	`596`	`TryCopyTo(s, destination, out charsWritten) :`
Original file line number	Diff line number	Diff line change
`@@ -538,8 +538,7 @@ private unsafe void GenerateNames()`
`538`	`538`	`/// </summary>`
`539`	`539`	`private unsafe string? GetServiceKeyName(SafeServiceHandle? SCMHandle, string serviceDisplayName)`
`540`	`540`	`{`
`541`		`- Span<char> initialBuffer = stackalloc char[256];`
`542`		`- var builder = new ValueStringBuilder(initialBuffer);`
	`541`	`+ var builder = new ValueStringBuilder(stackalloc char[256]);`
`543`	`542`	`int bufLen;`
`544`	`543`	`while (true)`
`545`	`544`	`{`