Add tests for TryCastArray methods

src/flatcollections-array/FlatArray.Tests/Tests.FlatArray.T/Cast/TryCastArray.cs

@@ -0,0 +1,78 @@
+using System;
+using Xunit;
+using static PrimeFuncPack.UnitTest.TestData;
+
+namespace PrimeFuncPack.Core.Tests;
+
+partial class FlatArrayTest
+{
+    [Theory]
+    [InlineData(false)]
+    [InlineData(true)]
+    public static void TryCastArray_CastIsInvalid_ExpectNull(
+        bool isSourceDefault)
+    {
+        var source = isSourceDefault ? default : new[] { PlusFifteen, Zero }.InitializeFlatArray();
+        var actual = source.TryCastArray<string>();
+
+        Assert.Null(actual);
+    }
+
+    [Theory]
+    [MemberData(nameof(TryCastArray_CastValueTypeIsValid_ExpectCastedInnerState_TestSource))]
+    public static void TryCastArray_CastValueTypeIsValid_ExpectCastedInnerState(
+        FlatArray<int> source, uint[]? expectedItems)
+    {
+        var actual = source.TryCastArray<uint>();
+
+        Assert.NotNull(actual);
+        actual.Value.VerifyTruncatedState(expectedItems);
+    }
+
+    [Theory]
+    [MemberData(nameof(TryCastArray_CastRefTypeIsValid_ExpectCastedInnerState_TestSource))]
+    public static void TryCastArray_CastRefTypeIsValid_ExpectCastedInnerState(
+        FlatArray<string?> source, object?[]? expectedItems)
+    {
+        var actual = source.TryCastArray<object?>();
+
+        Assert.NotNull(actual);
+        actual.Value.VerifyTruncatedState(expectedItems);
+    }
+
+    public static TheoryData<FlatArray<int>, uint[]?> TryCastArray_CastValueTypeIsValid_ExpectCastedInnerState_TestSource
+        =>
+        new()
+        {
+            {
+                default,
+                default
+            },
+            {
+                new int[] { PlusFifteen, Zero, One }.InitializeFlatArray(),
+                [ PlusFifteen, Zero, One ]
+            },
+            {
+                new int[] { int.MaxValue, One, PlusFifteen, Zero, MinusOne }.InitializeFlatArray(4),
+                [ int.MaxValue, One, PlusFifteen, Zero ]
+            }
+        };
+
+    public static TheoryData<FlatArray<string?>, object?[]?> TryCastArray_CastRefTypeIsValid_ExpectCastedInnerState_TestSource
+        =>
+        new()
+        {
+            {
+                default,
+                default
+            },
+            {
+                new string?[] { SomeString, null }.InitializeFlatArray(),
+                [ SomeString, null ]
+            },
+            {
+                new string?[] { null, AnotherString, EmptyString, UpperAnotherString, WhiteSpaceString }.InitializeFlatArray(3),
+                [ null, AnotherString, EmptyString ]
+            }
+        };
+}

src/flatcollections-array/FlatArray/FlatArray.T/Cast/Cast.CastArray.Try.cs

@@ -2,8 +2,7 @@
 
 partial struct FlatArray<T>
 {
-    // TODO: Add the tests and make public
-    internal FlatArray<TResult>? TryCastArray<TResult>()
+    public FlatArray<TResult>? TryCastArray<TResult>()
     {
         // Safe array cast: 'as' cast