Add Regex.EnumerateMatches

api_list.include.md

@@ -214,8 +214,10 @@
  * `Boolean TryCopyTo(Span<Char>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.string.trycopyto)
 
 
-#### RegularExpressions.Regex
+#### Regex
 
+ * `ValueMatchEnumerator EnumerateMatches(ReadOnlySpan<Char>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.enumeratematches#system-text-regularexpressions-regex-enumeratematches(system-readonlyspan((system-char))))
+ * `ValueMatchEnumerator EnumerateMatches(ReadOnlySpan<Char>, Int32)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.enumeratematches#system-text-regularexpressions-regex-enumeratematches(system-readonlyspan((system-char))-system-int32))
  * `Boolean IsMatch(ReadOnlySpan<Char>, Int32)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-int32))
  * `Boolean IsMatch(ReadOnlySpan<Char>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))))
 
@@ -300,8 +302,8 @@
 
 #### RegexPolyfill
 
- * `Boolean IsMatch(String, RegularExpressions.RegexOptions, TimeSpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions-system-timespan))
- * `Boolean IsMatch(String, RegularExpressions.RegexOptions)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions))
+ * `Boolean IsMatch(String, RegexOptions, TimeSpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions-system-timespan))
+ * `Boolean IsMatch(String, RegexOptions)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions))
  * `Boolean IsMatch(String)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string))
 
 

readme.md

@@ -570,8 +570,10 @@ The class `Polyfill` includes the following extension methods:
  * `Boolean TryCopyTo(Span<Char>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.string.trycopyto)
 
 
-#### RegularExpressions.Regex
+#### Regex
 
+ * `ValueMatchEnumerator EnumerateMatches(ReadOnlySpan<Char>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.enumeratematches#system-text-regularexpressions-regex-enumeratematches(system-readonlyspan((system-char))))
+ * `ValueMatchEnumerator EnumerateMatches(ReadOnlySpan<Char>, Int32)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.enumeratematches#system-text-regularexpressions-regex-enumeratematches(system-readonlyspan((system-char))-system-int32))
  * `Boolean IsMatch(ReadOnlySpan<Char>, Int32)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-int32))
  * `Boolean IsMatch(ReadOnlySpan<Char>)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))))
 
@@ -656,8 +658,8 @@ The class `Polyfill` includes the following extension methods:
 
 #### RegexPolyfill
 
- * `Boolean IsMatch(String, RegularExpressions.RegexOptions, TimeSpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions-system-timespan))
- * `Boolean IsMatch(String, RegularExpressions.RegexOptions)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions))
+ * `Boolean IsMatch(String, RegexOptions, TimeSpan)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions-system-timespan))
+ * `Boolean IsMatch(String, RegexOptions)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions))
  * `Boolean IsMatch(String)` [reference](https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.ismatch#system-text-regularexpressions-regex-ismatch(system-readonlyspan((system-char))-system-string))
 
 <!-- endInclude -->

src/Polyfill/Regex/Polyfill_Regex.cs

@@ -2,14 +2,10 @@
 
 #pragma warning disable
 
-#if (MEMORYREFERENCED && !NET7_0_OR_GREATER)
+#if !NET7_0_OR_GREATER && HAS_SPAN
 
 using System;
-using System.IO;
-using System.Net.Http;
 using System.Text.RegularExpressions;
-using System.Threading;
-using System.Threading.Tasks;
 using Link = System.ComponentModel.DescriptionAttribute;
 
 static partial class Polyfill
@@ -33,5 +29,45 @@ public static bool IsMatch(this Regex target, ReadOnlySpan<char> input)
     {
         return target.IsMatch(input.ToString());
     }
+
+    /// <summary>
+    /// Searches an input span for all occurrences of a regular expression and returns a Regex.ValueMatchEnumerator to iterate over the matches.
+    /// </summary>
+    /// <returns>A Regex.ValueMatchEnumerator to iterate over the matches.</returns>
+    [Link("https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.enumeratematches#system-text-regularexpressions-regex-enumeratematches(system-readonlyspan((system-char)))")]
+    public static ValueMatchEnumerator EnumerateMatches (this Regex target, ReadOnlySpan<char> input) =>
+        new(target, input, target.RightToLeft ? input.Length : 0);
+
+    /// <summary>
+    /// Searches an input span for all occurrences of a regular expression and returns a Regex.ValueMatchEnumerator to iterate over the matches.
+    /// </summary>
+    /// <returns>A Regex.ValueMatchEnumerator to iterate over the matches.</returns>
+    [Link("https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.enumeratematches#system-text-regularexpressions-regex-enumeratematches(system-readonlyspan((system-char))-system-int32)")]
+    public static ValueMatchEnumerator EnumerateMatches (this Regex target, ReadOnlySpan<char> input, int startat) =>
+        new(target, input, startat);
+    //
+    // /// <summary>
+    // /// Searches an input span for all occurrences of a regular expression and returns a Regex.ValueMatchEnumerator to iterate over the matches.
+    // /// </summary>
+    // /// <returns>A Regex.ValueMatchEnumerator to iterate over the matches.</returns>
+    // [Link("https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.enumeratematches#system-text-regularexpressions-regex-enumeratematches(system-readonlyspan((system-char))-system-string)")]
+    // public static ValueMatchEnumerator EnumerateMatches (this Regex target, ReadOnlySpan<char> input, string pattern) =>
+    //     new(target, input, target.RightToLeft ? input.Length : 0);
+    //
+    // /// <summary>
+    // /// Searches an input span for all occurrences of a regular expression and returns a Regex.ValueMatchEnumerator to iterate over the matches.
+    // /// </summary>
+    // /// <returns>A Regex.ValueMatchEnumerator to iterate over the matches.</returns>
+    // [Link("https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.enumeratematches#system-text-regularexpressions-regex-enumeratematches(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions)")]
+    // public static ValueMatchEnumerator EnumerateMatches (this Regex target, ReadOnlySpan<char> input, string pattern, System.Text.RegularExpressions.RegexOptions options) =>
+    //     new(target, input, target.RightToLeft ? input.Length : 0);
+    //
+    // /// <summary>
+    // /// Searches an input span for all occurrences of a regular expression and returns a Regex.ValueMatchEnumerator to iterate over the matches.
+    // /// </summary>
+    // /// <returns>A Regex.ValueMatchEnumerator to iterate over the matches.</returns>
+    // [Link("https://learn.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex.enumeratematches#system-text-regularexpressions-regex-enumeratematches(system-readonlyspan((system-char))-system-string-system-text-regularexpressions-regexoptions-system-timespan)")]
+    // public static ValueMatchEnumerator EnumerateMatches (this Regex target, ReadOnlySpan<char> input, string pattern, System.Text.RegularExpressions.RegexOptions options, TimeSpan matchTimeout) =>
+    //     new(target, input, target.RightToLeft ? input.Length : 0);
 }
 #endif

src/Polyfill/Regex/RegexPolyfill.cs

@@ -1,9 +1,7 @@
 // <auto-generated />
 
 #pragma warning disable
-#if MEMORYREFERENCED
 using System;
-using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Text.RegularExpressions;
 using Link = System.ComponentModel.DescriptionAttribute;
@@ -14,6 +12,7 @@
 #endif
 static partial class RegexPolyfill
 {
+#if HAS_SPAN
     /// <summary>
     /// Indicates whether the specified regular expression finds a match in the specified input span, using the specified matching options and time-out interval.
     /// </summary>
@@ -55,5 +54,5 @@ public static bool IsMatch(ReadOnlySpan<char> input, string pattern)
        return Regex.IsMatch(input.ToString(), pattern);
 #endif
     }
-}
 #endif
+}

src/Polyfill/Regex/ValueMatch.cs

@@ -0,0 +1,50 @@
+// <auto-generated />
+
+#pragma warning disable
+
+#if !NET7_0_OR_GREATER && HAS_SPAN
+
+using System;
+using System.Diagnostics.CodeAnalysis;
+
+namespace System.Text.RegularExpressions;
+
+/// <summary>
+/// Represents the results from a single regular expression match.
+/// </summary>
+/// <remarks>
+/// The <see cref="ValueMatch"/> type is immutable and has no public constructor. An instance of the <see cref="ValueMatch"/> struct is returned by the
+/// <see cref="Regex.ValueMatchEnumerator.Current"/> method when iterating over the results from calling <see cref="Regex.EnumerateMatches(ReadOnlySpan{char})"/>.
+/// </remarks>
+[ExcludeFromCodeCoverage]
+#if PolyPublic
+public
+#endif
+readonly ref struct ValueMatch
+{
+    private readonly int _index;
+    private readonly int _length;
+
+    /// <summary>
+    /// Crates an instance of the <see cref="ValueMatch"/> type based on the passed in <paramref name="index"/> and <paramref name="length"/>.
+    /// </summary>
+    /// <param name="index">The position in the original span where the first character of the captured sliced span is found.</param>
+    /// <param name="length">The length of the captured sliced span.</param>
+    internal ValueMatch(int index, int length)
+    {
+        _index = index;
+        _length = length;
+    }
+
+    /// <summary>
+    /// Gets the position in the original span where the first character of the captured sliced span is found.
+    /// </summary>
+    public int Index => _index;
+
+    /// <summary>
+    /// Gets the length of the captured sliced span.
+    /// </summary>
+    public int Length => _length;
+}
+
+#endif

src/Polyfill/Regex/ValueMatchEnumerator.cs

@@ -0,0 +1,79 @@
+// <auto-generated />
+
+#pragma warning disable
+
+#if !NET7_0_OR_GREATER && HAS_SPAN
+
+using System;
+using System.Diagnostics.CodeAnalysis;
+
+namespace System.Text.RegularExpressions;
+
+/// <summary>
+/// Represents an enumerator containing the set of successful matches found by iteratively applying a regular expression pattern to the input span.
+/// </summary>
+/// <remarks>
+/// The enumerator has no public constructor. The <see cref="Regex.EnumerateMatches(ReadOnlySpan{char})"/> method returns a <see cref="Regex.ValueMatchEnumerator"/>
+/// object.The enumerator will lazily iterate over zero or more <see cref="ValueMatch"/> objects. If there is at least one successful match in the span, then
+/// <see cref="MoveNext"/> returns <see langword="true"/> and <see cref="Current"/> will contain the first <see cref="ValueMatch"/>. If there are no successful matches,
+/// then <see cref="MoveNext"/> returns <see langword="false"/> and <see cref="Current"/> throws an <see cref="InvalidOperationException"/>.
+///
+/// This type is a ref struct since it stores the input span as a field in order to be able to lazily iterate over it.
+/// </remarks>
+[ExcludeFromCodeCoverage]
+#if PolyPublic
+public
+#endif
+ref struct ValueMatchEnumerator
+{
+    ReadOnlySpan<char> _input;
+    ValueMatch _current;
+    MatchCollection matchCollection;
+    int index = 0;
+
+    /// <summary>
+    /// Creates an instance of the <see cref="ValueMatchEnumerator"/> for the passed in <paramref name="regex"/> which iterates over <paramref name="input"/>.
+    /// </summary>
+    /// <param name="regex">The <see cref="Regex"/> to use for finding matches.</param>
+    /// <param name="input">The input span to iterate over.</param>
+    /// <param name="startAt">The position where the engine should start looking for matches from.</param>
+    internal ValueMatchEnumerator(Regex regex, ReadOnlySpan<char> input, int startAt)
+    {
+        matchCollection = regex.Matches(input.ToString(), startAt);
+        _input = input;
+        _current = default;
+    }
+
+    /// <summary>
+    /// Provides an enumerator that iterates through the matches in the input span.
+    /// </summary>
+    /// <returns>A copy of this enumerator.</returns>
+    public readonly ValueMatchEnumerator GetEnumerator() => this;
+
+    /// <summary>
+    /// Advances the enumerator to the next match in the span.
+    /// </summary>
+    /// <returns>
+    /// <see langword="true"/> if the enumerator was successfully advanced to the next element; <see langword="false"/> if the enumerator cannot find additional matches.
+    /// </returns>
+    public bool MoveNext()
+    {
+        if (index == matchCollection.Count)
+        {
+            return false;
+        }
+
+        var match = matchCollection[index];
+        _current = new ValueMatch(match.Index, match.Length);
+        index++;
+        return true;
+    }
+
+    /// <summary>
+    /// Gets the <see cref="ValueMatch"/> element at the current position of the enumerator.
+    /// </summary>
+    /// <exception cref="InvalidOperationException">Enumeration has either not started or has already finished.</exception>
+    public readonly ValueMatch Current => _current;
+}
+
+#endif

src/Tests/BuildApiTest.cs

@@ -1,12 +1,13 @@
+#if NET8_0 && DEBUG
 using System.Diagnostics.CodeAnalysis;
 using Mono.Cecil;
 
-#if NET8_0 && DEBUG
 [TestFixture]
 class BuildApiTest
 {
     static string[] namespacesToClean =
     [
+        "System.Text.RegularExpressions.",
         "System.Diagnostics.",
         "System.Collections.Generic.",
         "System.Threading.Tasks.",

src/Tests/PolyfillTests_Regex.cs

@@ -0,0 +1,28 @@
+using System.Text.RegularExpressions;
+
+partial class PolyfillTests
+{
+    [Test]
+    public void RegexIsMatch()
+    {
+        var regex = new Regex(@"\d+");
+        var match = regex.Match("a55a");
+        Assert.IsTrue(match.Success);
+    }
+
+    [Test]
+    public void EnumerateMatches()
+    {
+        var regex = new Regex(@"\d+");
+        var span = "a55a".AsSpan();
+        var found = false;
+        foreach (var match in regex.EnumerateMatches(span))
+        {
+            found = true;
+            Assert.AreEqual(1, match.Index);
+            Assert.AreEqual(2, match.Length);
+        }
+
+        Assert.IsTrue(found);
+    }
+}