Add some DebuggerDisplay attributes in System.Linq (dotnet/corefx#41386)

stephentoub · safern · commit c362923cae85 · 2019-09-27T11:19:52.000-07:00
Commit migrated from dotnet/corefx@e667c29
diff --git a/src/libraries/System.Linq/src/System/Linq/Partition.SpeedOpt.cs b/src/libraries/System.Linq/src/System/Linq/Partition.SpeedOpt.cs
@@ -17,6 +17,7 @@ namespace System.Linq
     /// Returning an instance of this type is useful to quickly handle scenarios where it is known
     /// that an operation will result in zero elements.
     /// </remarks>
+    [DebuggerDisplay("Count = 0")]
     internal sealed class EmptyPartition<TElement> : IPartition<TElement>, IEnumerator<TElement>
     {
         /// <summary>
@@ -150,6 +151,7 @@ public static partial class Enumerable
         /// An iterator that yields the items of part of an <see cref="IList{TSource}"/>.
         /// </summary>
         /// <typeparam name="TSource">The type of the source list.</typeparam>
+        [DebuggerDisplay("Count = {Count}")]
         private sealed class ListPartition<TSource> : Iterator<TSource>, IPartition<TSource>
         {
             private readonly IList<TSource> _source;
diff --git a/src/libraries/System.Linq/src/System/Linq/Range.cs b/src/libraries/System.Linq/src/System/Linq/Range.cs
@@ -28,6 +28,7 @@ public static IEnumerable<int> Range(int start, int count)
         /// <summary>
         /// An iterator that yields a range of consecutive integers.
         /// </summary>
+        [DebuggerDisplay("Count = {CountForDebugger}")]
         private sealed partial class RangeIterator : Iterator<int>
         {
             private readonly int _start;
@@ -40,6 +41,8 @@ public RangeIterator(int start, int count)
                 _end = unchecked(start + count);
             }
 
+            private int CountForDebugger => _end - _start;
+
             public override Iterator<int> Clone() => new RangeIterator(_start, _end - _start);
 
             public override bool MoveNext()
diff --git a/src/libraries/System.Linq/src/System/Linq/Repeat.cs b/src/libraries/System.Linq/src/System/Linq/Repeat.cs
@@ -28,6 +28,7 @@ public static IEnumerable<TResult> Repeat<TResult>(TResult element, int count)
         /// An iterator that yields the same item multiple times.
         /// </summary>
         /// <typeparam name="TResult">The type of the item.</typeparam>
+        [DebuggerDisplay("Count = {_count}")]
         private sealed partial class RepeatIterator<TResult> : Iterator<TResult>
         {
             private readonly int _count;
diff --git a/src/libraries/System.Linq/src/System/Linq/Select.SpeedOpt.cs b/src/libraries/System.Linq/src/System/Linq/Select.SpeedOpt.cs
@@ -683,6 +683,7 @@ public int GetCount(bool onlyIfCheap)
         /// </summary>
         /// <typeparam name="TSource">The type of the source list.</typeparam>
         /// <typeparam name="TResult">The type of the mapped items.</typeparam>
+        [DebuggerDisplay("Count = {Count}")]
         private sealed class SelectListPartitionIterator<TSource, TResult> : Iterator<TResult>, IPartition<TResult>
         {
             private readonly IList<TSource> _source;
diff --git a/src/libraries/System.Linq/src/System/Linq/Select.cs b/src/libraries/System.Linq/src/System/Linq/Select.cs
@@ -156,6 +156,7 @@ public override IEnumerable<TResult2> Select<TResult2>(Func<TResult, TResult2> s
         /// </summary>
         /// <typeparam name="TSource">The type of the source array.</typeparam>
         /// <typeparam name="TResult">The type of the mapped items.</typeparam>
+        [DebuggerDisplay("Count = {CountForDebugger}")]
         private sealed partial class SelectArrayIterator<TSource, TResult> : Iterator<TResult>
         {
             private readonly TSource[] _source;
@@ -170,6 +171,8 @@ public SelectArrayIterator(TSource[] source, Func<TSource, TResult> selector)
                 _selector = selector;
             }
 
+            private int CountForDebugger => _source.Length;
+
             public override Iterator<TResult> Clone() => new SelectArrayIterator<TSource, TResult>(_source, _selector);
 
             public override bool MoveNext()
@@ -194,6 +197,7 @@ public override IEnumerable<TResult2> Select<TResult2>(Func<TResult, TResult2> s
         /// </summary>
         /// <typeparam name="TSource">The type of the source list.</typeparam>
         /// <typeparam name="TResult">The type of the mapped items.</typeparam>
+        [DebuggerDisplay("Count = {CountForDebugger}")]
         private sealed partial class SelectListIterator<TSource, TResult> : Iterator<TResult>
         {
             private readonly List<TSource> _source;
@@ -208,6 +212,8 @@ public SelectListIterator(List<TSource> source, Func<TSource, TResult> selector)
                 _selector = selector;
             }
 
+            private int CountForDebugger => _source.Count;
+
             public override Iterator<TResult> Clone() => new SelectListIterator<TSource, TResult>(_source, _selector);
 
             public override bool MoveNext()
@@ -241,6 +247,7 @@ public override IEnumerable<TResult2> Select<TResult2>(Func<TResult, TResult2> s
         /// </summary>
         /// <typeparam name="TSource">The type of the source list.</typeparam>
         /// <typeparam name="TResult">The type of the mapped items.</typeparam>
+        [DebuggerDisplay("Count = {CountForDebugger}")]
         private sealed partial class SelectIListIterator<TSource, TResult> : Iterator<TResult>
         {
             private readonly IList<TSource> _source;
@@ -255,6 +262,8 @@ public SelectIListIterator(IList<TSource> source, Func<TSource, TResult> selecto
                 _selector = selector;
             }
 
+            private int CountForDebugger => _source.Count;
+
             public override Iterator<TResult> Clone() => new SelectIListIterator<TSource, TResult>(_source, _selector);
 
             public override bool MoveNext()

Original file line number	Diff line number	Diff line change
`@@ -28,6 +28,7 @@ public static IEnumerable<int> Range(int start, int count)`
`28`	`28`	`/// <summary>`
`29`	`29`	`/// An iterator that yields a range of consecutive integers.`
`30`	`30`	`/// </summary>`
	`31`	`+ [DebuggerDisplay("Count = {CountForDebugger}")]`
`31`	`32`	`private sealed partial class RangeIterator : Iterator<int>`
`32`	`33`	`{`
`33`	`34`	`private readonly int _start;`
`@@ -40,6 +41,8 @@ public RangeIterator(int start, int count)`
`40`	`41`	`_end = unchecked(start + count);`
`41`	`42`	`}`
`42`	`43`
	`44`	`+ private int CountForDebugger => _end - _start;`
	`45`	`+`
`43`	`46`	`public override Iterator<int> Clone() => new RangeIterator(_start, _end - _start);`
`44`	`47`
`45`	`48`	`public override bool MoveNext()`
Original file line number	Diff line number	Diff line change
`@@ -683,6 +683,7 @@ public int GetCount(bool onlyIfCheap)`
`683`	`683`	`/// </summary>`
`684`	`684`	`/// <typeparam name="TSource">The type of the source list.</typeparam>`
`685`	`685`	`/// <typeparam name="TResult">The type of the mapped items.</typeparam>`
	`686`	`+ [DebuggerDisplay("Count = {Count}")]`
`686`	`687`	`private sealed class SelectListPartitionIterator<TSource, TResult> : Iterator<TResult>, IPartition<TResult>`
`687`	`688`	`{`
`688`	`689`	`private readonly IList<TSource> _source;`