Improve Stryker Coverage

src/FlatSharp.Runtime/Vectors/VectorsCommon.cs

@@ -21,6 +21,12 @@ namespace FlatSharp.Internal;
 /// </summary>
 public static class VectorsCommon
 {
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static bool Contains<T>(IList<T> vector, T? item)
+    {
+        return IndexOf<T>(vector, item) >= 0;
+    }
+
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static int IndexOf<T>(IList<T> vector, T? item)
     {

src/FlatSharp/FlatBufferVectorHelpers.cs

@@ -64,7 +64,8 @@ public static string CreateCommonReadOnlyVectorMethods(
         string nullableReference = GetNullableReferenceAnnotation(itemTypeModel);
 
         return $$"""
-            public bool Contains({{baseTypeName}}{{nullableReference}} item) => this.IndexOf(item) >= 0;
+            public bool Contains({{baseTypeName}}{{nullableReference}} item)
+                => {{typeof(VectorsCommon).GetGlobalCompilableTypeName()}}.Contains(this, item);
 
             public int IndexOf({{baseTypeName}}{{nullableReference}} item)
                 => {{typeof(VectorsCommon).GetGlobalCompilableTypeName()}}.IndexOf(this, item);
@@ -84,6 +85,7 @@ private static string GetEfficientMultiply(
         string indexVariableName)
     {
         FlatSharpInternal.Assert(inlineSize != 0, "invalid inline size");
+
         bool isPowerOf2 = (inlineSize & (inlineSize - 1)) == 0;
         if (!isPowerOf2)
         {

src/FlatSharp/FlatBufferVectorHelpers_LazyUnion.cs

@@ -92,7 +92,11 @@ internal sealed class {{className}}<TInputBuffer>
         public {{baseTypeName}} this[int index]
         {
             get => this.SafeParseItem(index);
-            set => this.WriteThrough(index, value);
+            set
+            {
+                {{nameof(VectorUtilities)}}.{{nameof(VectorUtilities.CheckIndex)}}(index, this.count);
+                this.WriteThrough(index, value);
+            }
         }
 
         public int Count => this.count;

src/FlatSharp/FlatBufferVectorHelpers_ProgressiveUnion.cs

@@ -192,6 +192,8 @@ private static void GetAddress(uint index, out uint rowIndex, out uint colIndex)
                         int absoluteStartIndex = (int)({{GetEfficientMultiply(chunkSize, "rowIndex")}});
                         int copyCount = {{chunkSize}};
                         int remainingItems = this.count - absoluteStartIndex;
+
+                        {{StrykerSuppressor.SuppressNextLine("equality")}}
                         if (remainingItems < {{chunkSize}})
                         {
                             copyCount = remainingItems;
@@ -235,6 +237,7 @@ private static void GetAddress(uint index, out uint rowIndex, out uint colIndex)
 
         private void ProgressiveSet(int index, {{baseTypeName}} value)
         {
+            {{nameof(VectorUtilities)}}.{{nameof(VectorUtilities.CheckIndex)}}(index, this.count);
             {{nameof(VectorUtilities)}}.{{nameof(VectorUtilities.ThrowInlineNotMutableException)}}();
         }
 

src/Tests/FlatSharpEndToEndTests/Helpers.cs

@@ -16,9 +16,11 @@
 
 using FlatSharp.Internal;
 using System;
+using System.Collections.Generic;
 using System.Linq.Expressions;
 using System.Reflection;
 using System.Threading;
+using Xunit.Abstractions;
 
 namespace FlatSharpEndToEndTests;
 
@@ -97,7 +99,8 @@ public static void AssertMutationWorks<TSource, TProperty>(
         TSource parent,
         bool isWriteThrough,
         Expression<Func<TSource, TProperty>> propertyLambda,
-        TProperty newValue)
+        TProperty newValue,
+        Action<TProperty, TProperty>? assertEqual = null)
     {
         Assert.True(parent is IFlatBufferDeserializedObject);
 
@@ -124,33 +127,26 @@ public static void AssertMutationWorks<TSource, TProperty>(
 
         MemberExpression member = propertyLambda.Body as MemberExpression;
         PropertyInfo propInfo = member.Member as PropertyInfo;
-        Action action = () => propInfo.SetMethod.Invoke(parent, new object[] { newValue });
+
+        Func<TProperty> get = () => (TProperty)propInfo.GetMethod.Invoke(parent, null);
+        Action set = () => propInfo.SetMethod.Invoke(parent, new object[] { newValue });
+
+        // should be equal to itself to start with.
+        AssertEquality(option, get(), get(), assertEqual);
 
         switch (option)
         {
             case FlatBufferDeserializationOption.Lazy when isWriteThrough:
             case FlatBufferDeserializationOption.Progressive when isWriteThrough:
             case FlatBufferDeserializationOption.GreedyMutable when isWriteThrough is false:
-                action();
-
-                // For value types, validate that they are the same.
-                if (typeof(TProperty).IsValueType)
-                {
-                    TProperty readValue = (TProperty)propInfo.GetMethod.Invoke(parent, null);
-                    Assert.Equal<TProperty>(newValue, readValue);
-                }
-                else if (option != FlatBufferDeserializationOption.Lazy)
-                {
-                    TProperty readValue = (TProperty)propInfo.GetMethod.Invoke(parent, null);
-                    Assert.True(object.ReferenceEquals(newValue, readValue));
-                }
-
+                set();
+                AssertEquality(option, newValue, get(), assertEqual);
                 return;
 
             default:
                 var ex = Assert.Throws<NotMutableException>(new Action(() =>
                 {
-                    var ex = Assert.Throws<TargetInvocationException>(action).InnerException;
+                    var ex = Assert.Throws<TargetInvocationException>(set).InnerException;
                     throw ex;
                 }));
 
@@ -169,12 +165,8 @@ public static void ValidateListVector<T>(
         IList<T> items,
         T newValue)
     {
-        // This can be lots of things: NotMutable, ArgumentOfRange, IndexOutOfRange, etc.
-        Assert.ThrowsAny<Exception>(() => items[-1]);
-        Assert.ThrowsAny<Exception>(() => items[items.Count]);
-        Assert.ThrowsAny<Exception>(() => items[-1] = default);
-        Assert.ThrowsAny<Exception>(() => items[items.Count] = default);
-
+        CheckRangeExceptions(option, isWriteThrough, items);
+
         if (items is IFlatBufferDeserializedVector vec)
         {
             Assert.ThrowsAny<IndexOutOfRangeException>(() => vec.OffsetOf(-1));
@@ -419,4 +411,52 @@ IEnumerator IEnumerable.GetEnumerator()
             return ((IEnumerable)list).GetEnumerator();
         }
     }
+
+    private static void AssertEquality<T>(FlatBufferDeserializationOption option, T a, T b, Action<T, T>? assertEqual)
+    {
+        if (assertEqual is null)
+        {
+            if (typeof(T).IsValueType && (typeof(T).IsPrimitive || typeof(T).IsEnum))
+            {
+                assertEqual = (a, b) => Assert.Equal(a, b);
+            }
+            else if (typeof(T) == typeof(string))
+            {
+                assertEqual = (a, b) => Assert.Equal(a, b);
+            }
+        }
+
+        if (!typeof(T).IsValueType && option != FlatBufferDeserializationOption.Lazy)
+        {
+            Assert.True(object.ReferenceEquals(a, b));
+        }
+
+        assertEqual?.Invoke(a, b);
+    }
+
+    private static void CheckRangeExceptions<T>(FlatBufferDeserializationOption option, bool isWriteThrough, IList<T> list)
+    {
+        if (option == FlatBufferDeserializationOption.Lazy || option == FlatBufferDeserializationOption.Progressive)
+        {
+            Assert.Throws<IndexOutOfRangeException>(() => list[-1]);
+            Assert.Throws<IndexOutOfRangeException>(() => list[list.Count]);
+            Assert.Throws<IndexOutOfRangeException>(() => list[-1] = default);
+            Assert.Throws<IndexOutOfRangeException>(() => list[list.Count] = default);
+        }
+        else if (option == FlatBufferDeserializationOption.Greedy
+             || (isWriteThrough && option == FlatBufferDeserializationOption.GreedyMutable))
+        {
+            Assert.Throws<ArgumentOutOfRangeException>(() => list[-1]);
+            Assert.Throws<ArgumentOutOfRangeException>(() => list[list.Count]);
+            Assert.Throws<NotMutableException>(() => list[-1] = default);
+            Assert.Throws<NotMutableException>(() => list[list.Count] = default);
+        }
+        else
+        {
+            Assert.Throws<ArgumentOutOfRangeException>(() => list[-1]);
+            Assert.Throws<ArgumentOutOfRangeException>(() => list[list.Count]);
+            Assert.Throws<ArgumentOutOfRangeException>(() => list[-1] = default);
+            Assert.Throws<ArgumentOutOfRangeException>(() => list[list.Count] = default);
+        }
+    }
 }

src/Tests/Stryker/Tests/FullTreeTests.cs

@@ -22,17 +22,39 @@ public void RootMutations(FlatBufferDeserializationOption option)
     [ClassData(typeof(DeserializationOptionClassData))]
     public void VectorFieldMutations(FlatBufferDeserializationOption option)
     {
+        static void AssertMemoryEqual(Memory<byte>? a, Memory<byte>? b)
+        {
+            Assert.Equal(a is null, b is null);
+            if (a is null)
+            {
+                return;
+            }
+
+            Helpers.AssertSequenceEqual(a.Value.Span, b.Value.Span);
+        }
+
         Vectors vectors = this.CreateRoot().SerializeAndParse(option).Vectors;
 
         Helpers.AssertMutationWorks(option, vectors, false, r => r.Indexed, null);
-        Helpers.AssertMutationWorks(option, vectors, false, r => r.Memory, null);
+        Helpers.AssertMutationWorks(option, vectors, false, r => r.Memory, null, AssertMemoryEqual);
         Helpers.AssertMutationWorks(option, vectors, false, r => r.RefStruct, null);
         Helpers.AssertMutationWorks(option, vectors, false, r => r.Str, null);
         Helpers.AssertMutationWorks(option, vectors, false, r => r.Table, null);
         Helpers.AssertMutationWorks(option, vectors, false, r => r.Union, null);
         Helpers.AssertMutationWorks(option, vectors, false, r => r.ValueStruct, null);
     }
 
+    [Fact]
+    public void VectorFieldTests_ProgressiveClear()
+    {
+        Vectors vectors = this.CreateRoot().SerializeAndParse(FlatBufferDeserializationOption.Progressive, out byte[] data).Vectors;
+        Helpers.AssertSequenceEqual(new byte[] { 1, 2, 3, 4, }, vectors.Memory.Value.Span);
+
+        data.AsSpan().Clear();
+
+        Helpers.AssertSequenceEqual(new byte[] { 0, 0, 0, 0, }, vectors.Memory.Value.Span);
+    }
+
     [Fact]
     public void GetMaxSize()
     {

src/Tests/Stryker/Tests/ScalarFieldTests.cs

@@ -0,0 +1,51 @@
+using FlatSharp.Internal;
+using System.Linq.Expressions;
+
+namespace FlatSharpStrykerTests;
+
+public class ScalarFieldTests
+{
+    [Theory]
+    [ClassData(typeof(DeserializationOptionClassData))]
+    public void ValueStructTableField(FlatBufferDeserializationOption option)
+    {
+        Root r = CreateTableWithScalarField(out byte[] buffer);
+        Root parsed = r.SerializeAndParse(option, out byte[] actual);
+
+        Assert.Equal(r.Fields.Memory, parsed.Fields.Memory);
+        Helpers.AssertSequenceEqual(buffer, actual);
+    }
+
+    private static Root CreateTableWithScalarField(out byte[] expectedBuffer)
+    {
+        Root root = new Root
+        {
+            Fields = new()
+            {
+                Memory = 3,
+            }
+        };
+
+        expectedBuffer = new byte[]
+        {
+            4, 0, 0, 0,         // offset to table start
+            248, 255, 255, 255, // soffset to vtable.
+            12, 0, 0, 0,        // uoffset to field 0 (fields table)
+            6, 0,               // vtable length
+            8, 0,               // table length
+            4, 0,               // offset of field 0
+            0, 0,               // padding
+
+            250, 255, 255, 255,  // soffset to vtable
+            3, 0,
+
+            10, 0,
+            5, 0,
+            0, 0,
+            0, 0,
+            4, 0,
+        };
+
+        return root;
+    }
+}

src/Tests/Stryker/Tests/StructFieldTests.cs

@@ -73,7 +73,16 @@ public void ValueStructTableField(FlatBufferDeserializationOption option)
                 };
 
                 Helpers.AssertSequenceEqual(expectedBytes, buffer);
-                Helpers.AssertMutationWorks(option, fields, false, p => p.ValueStruct, default);
+                Helpers.AssertMutationWorks(option, fields, false, p => p.ValueStruct, new ValueStruct(), (a, b) =>
+                {
+                    var av = a.Value;
+                    var bv = b.Value;
+
+                    Assert.Equal(av.A, bv.A);
+                    Assert.Equal(av.B, bv.B);
+                    Assert.Equal(av.C(0), bv.C(0));
+                    Assert.Equal(av.C(1), bv.C(1));
+                });
             }
         }
         finally
@@ -82,6 +91,27 @@ public void ValueStructTableField(FlatBufferDeserializationOption option)
         }
     }
 
+    [Fact]
+    public void ValueStructTableField_ProgressiveClear()
+    {
+        Root root = new Root() { Fields = new() { ValueStruct = new ValueStruct { A = 5 } } }.SerializeAndParse(FlatBufferDeserializationOption.Progressive, out byte[] buffer);
+
+        var fields = root.Fields;
+        Assert.Equal(5, fields.ValueStruct.Value.A);
+        buffer.AsSpan().Clear();
+        Assert.Equal(5, fields.ValueStruct.Value.A);
+    }
+
+    [Fact]
+    public void ValueStructStructField_ProgressiveClear()
+    {
+        Root root = new Root() { Fields = new() { RefStruct = new() { E = new ValueStruct { A = 5 } } } }.SerializeAndParse(FlatBufferDeserializationOption.Progressive, out byte[] buffer);
+
+        var fields = root.Fields.RefStruct;
+        Assert.Equal(5, fields.E.A);
+        buffer.AsSpan().Clear();
+        Assert.Equal(5, fields.E.A);
+    }
 
     [Theory]
     [ClassData(typeof(DeserializationOptionClassData))]
@@ -130,7 +160,13 @@ public void ReferenceStructWriteThrough(FlatBufferDeserializationOption option)
         Helpers.AssertMutationWorks(option, rsp, true, rsp => rsp.__flatsharp__C_1, (sbyte)6);
         Helpers.AssertMutationWorks(option, rsp, false, rsp => rsp.__flatsharp__D_0, (sbyte)3);
         Helpers.AssertMutationWorks(option, rsp, false, rsp => rsp.__flatsharp__D_1, (sbyte)6);
-        Helpers.AssertMutationWorks(option, rsp, false, rsp => rsp.E, new ValueStruct());
+        Helpers.AssertMutationWorks(option, rsp, false, rsp => rsp.E, new ValueStruct(), (a, b) =>
+        {
+            Assert.Equal(a.A, b.A);
+            Assert.Equal(a.B, b.B);
+            Assert.Equal(a.C(0), b.C(0));
+            Assert.Equal(a.C(1), b.C(1));
+        });
 
         var parsed2 = Root.Serializer.Parse(buffer, option);
 

src/Tests/Stryker/Tests/UnionFieldTests.cs

@@ -27,6 +27,19 @@ public void InvalidGetters()
         Assert.Throws<InvalidOperationException>(() => a.RefStruct);
     }
 
+    [Fact]
+    public void ProgressiveClear()
+    {
+        Root parsed = new Root { Fields = new() { Union = new FunUnion("hi") } }.SerializeAndParse(FlatBufferDeserializationOption.Progressive, out byte[] buffer);
+
+        Fields f = parsed.Fields;
+        Assert.Equal("hi", f.Union.Value.str);
+
+        buffer.AsSpan().Clear();
+
+        Assert.Equal("hi", f.Union.Value.str);
+    }
+
     [Theory]
     [ClassData(typeof(DeserializationOptionClassData))]
     public void StringMember(FlatBufferDeserializationOption option)
@@ -44,7 +57,13 @@ public void StringMember(FlatBufferDeserializationOption option)
         Assert.True(union.TryGet(out string str));
         Assert.Equal("hello", str);
 
-        Helpers.AssertMutationWorks(option, parsed.Fields, false, f => f.Union, default);
+        Helpers.AssertMutationWorks(option, parsed.Fields, false, f => f.Union, new FunUnion(string.Empty), (a, b) =>
+        {
+            var av = a.Value;
+            var bv = b.Value;
+            Assert.Equal(av.Discriminator, bv.Discriminator);
+            Assert.Equal(av.str, bv.str);
+        });
     }
 
     [Fact]