Add run-coverage.sh, improve Combinations logic, and enhance tests

Author: Necas209

DotNetExtensions.slnx

@@ -3,6 +3,7 @@
         <File Path=".github\workflows\codeql.yml" />
         <File Path=".github\workflows\dotnet.yml" />
         <File Path="global.json" />
+        <File Path="run-coverage.sh" />
     </Folder>
     <Project Path="DotNetExtensions\DotNetExtensions.csproj" />
     <Project Path="DotNetExtensionsTests\DotNetExtensionsTests.csproj" />

DotNetExtensions/Collections/Combinations.cs

@@ -22,19 +22,21 @@ public static IEnumerable<List<T>> Combinations<T>(this IEnumerable<T> source, i
         ArgumentNullException.ThrowIfNull(source);
         ArgumentOutOfRangeException.ThrowIfNegative(length);
 
+        if (length == 0)
+            return [[]];
+
+        if (source.TryGetNonEnumeratedCount(out var count))
+        {
+            if (length > count) return [];
+            if (length == count) return [source.ToList()];
+        }
+
         return CombinationsInternal(source, length);
     }
 
     private static IEnumerable<List<T>> CombinationsInternal<T>(IEnumerable<T> source, int length)
     {
-        var array = source as IList<T> ?? source.ToArray();
-
-        if (length == 0)
-        {
-            yield return [];
-            yield break;
-        }
-
+        var array = source as IList<T> ?? source.ToList();
         if (length > array.Count)
             yield break;
 

DotNetExtensions/DotNetExtensions.csproj

@@ -13,7 +13,7 @@
     </PropertyGroup>
 
     <PropertyGroup>
-        <Version>5.13.1</Version>
+        <Version>5.13.2</Version>
         <Authors>Diogo Medeiros</Authors>
         <Company>Diogo Medeiros</Company>
         <Description>This is a collection of extension methods for .NET Core.</Description>

DotNetExtensionsTests/Collections/CombinationsTests.cs

@@ -65,11 +65,20 @@ public async Task Combinations_LengthThree_ReturnsAllThreeElementCombinations()
         await Assert.That(result[9]).IsEquivalentTo([3, 4, 5]);
     }
 
+    [Test]
+    public async Task Combinations_LengthEqualsSource_ReturnsWholeSourceAsCombination()
+    {
+        var result = _defaultSource.Combinations(_defaultSource.Length).ToList();
+        await Assert.That(result).HasSingleItem();
+        await Assert.That(result[0]).IsEquivalentTo(_defaultSource);
+    }
+
     [Test]
     public async Task Combinations_LengthGreaterThanSource_ReturnsEmpty()
     {
-        var result = _defaultSource.Combinations(6).ToList();
-        await Assert.That(result).IsEmpty();
+        using var _ = Assert.Multiple();
+        await Assert.That(_defaultSource.Combinations(6)).IsEmpty();
+        await Assert.That(Numbers().Combinations(6).ToList()).IsEmpty();
     }
 
     [Test]

DotNetExtensionsTests/Collections/EnumerableExtensionsTests.cs

@@ -6,4 +6,13 @@ public partial class EnumerableExtensionsTests
 
     [Before(Class)]
     public static void Setup() => _defaultSource = [1, 2, 3, 4, 5];
+    
+    private static IEnumerable<int> Numbers()
+    {
+        yield return 1;
+        yield return 2;
+        yield return 3;
+        yield return 4;
+        yield return 5;
+    }
 }

DotNetExtensionsTests/Collections/SkipAtTests.cs

@@ -14,7 +14,9 @@ public async Task SkipAt_ValidIndex_RemovesElementAtIndex()
     [Test]
     public void SkipAt_IndexOutOfRange_ThrowsArgumentOutOfRangeException()
     {
-        Assert.ThrowsExactly<ArgumentOutOfRangeException>(() => _ = _defaultSource.SkipAt(5).ToList());
+        using var multiple = Assert.Multiple();
+        Assert.ThrowsExactly<ArgumentOutOfRangeException>(() => _ = _defaultSource.SkipAt(5));
+        Assert.ThrowsExactly<ArgumentOutOfRangeException>(() => _ = Numbers().SkipAt(5).ToList());
     }
 
     [Test]
@@ -27,7 +29,7 @@ public void SkipAt_NegativeIndex_ThrowsArgumentOutOfRangeException()
     public void SkipAt_EmptySource_ThrowsArgumentOutOfRangeException()
     {
         int[] source = [];
-        Assert.ThrowsExactly<ArgumentOutOfRangeException>(() => _ = source.SkipAt(0).ToList());
+        Assert.ThrowsExactly<ArgumentOutOfRangeException>(() => _ = source.SkipAt(0));
     }
 
     [Test]

DotNetExtensionsTests/DotNetExtensionsTests.csproj

@@ -1,18 +1,19 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-  <PropertyGroup>
-    <ImplicitUsings>enable</ImplicitUsings>
-    <Nullable>enable</Nullable>
-    <OutputType>Exe</OutputType>
-    <TargetFramework>net10.0</TargetFramework>
-  </PropertyGroup>
+    <PropertyGroup>
+        <TargetFramework>net10.0</TargetFramework>
+        <OutputType>Exe</OutputType>
+        <Nullable>enable</Nullable>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <LangVersion>latest</LangVersion>
+    </PropertyGroup>
 
-  <ItemGroup>
-    <PackageReference Include="TUnit" Version="1.*" />
-  </ItemGroup>
+    <ItemGroup>
+        <PackageReference Include="TUnit" Version="1.53.0" />
+    </ItemGroup>
 
-  <ItemGroup>
-    <ProjectReference Include="..\DotNetExtensions\DotNetExtensions.csproj" />
-  </ItemGroup>
+    <ItemGroup>
+        <ProjectReference Include="..\DotNetExtensions\DotNetExtensions.csproj" />
+    </ItemGroup>
 
-</Project>
+</Project>

run-coverage.sh

@@ -0,0 +1,30 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+RESULTS_DIR="TestResults"
+REPORT_DIR="$RESULTS_DIR/report"
+
+rm -rf "$RESULTS_DIR"
+mkdir -p "$RESULTS_DIR"
+
+dotnet test \
+  --coverage \
+  --results-directory "$RESULTS_DIR" \
+  --coverage-output-format xml \
+  --verbosity quiet
+
+COVERAGE_FILE="$(find "$RESULTS_DIR" -maxdepth 1 -type f -name '*.xml' | head -n 1)"
+
+if [ -z "$COVERAGE_FILE" ]; then
+  echo "No coverage XML file was generated."
+  exit 1
+fi
+
+reportgenerator \
+  -reports:"$COVERAGE_FILE" \
+  -targetdir:"$REPORT_DIR" \
+  -verbosity:Warning
+
+echo "Coverage report generated at: $REPORT_DIR"
+
+open "$REPORT_DIR/index.html"