test: add EF decimal parameterization test

Author: LiamHamsters

src/EFCore.Ydb/test/EntityFrameworkCore.Ydb.FunctionalTests/Query/DecimalParameterQueryYdbFixture.cs

@@ -0,0 +1,39 @@
+using EntityFrameworkCore.Ydb.FunctionalTests.TestUtilities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Diagnostics;
+using Microsoft.EntityFrameworkCore.TestUtilities;
+
+namespace EntityFrameworkCore.Ydb.FunctionalTests.Query;
+
+public class DecimalParameterQueryYdbFixture
+    : SharedStoreFixtureBase<DecimalParameterQueryYdbFixture.DecimalContext>
+{
+    private static DbCommandInterceptor? CurrentInterceptor => null;
+
+    protected override string StoreName => "DecimalParameter";
+    protected override ITestStoreFactory TestStoreFactory => YdbTestStoreFactory.Instance;
+
+    public override DbContextOptionsBuilder AddOptions(DbContextOptionsBuilder builder)
+    {
+        var b = base.AddOptions(builder);
+        if (CurrentInterceptor is not null)
+            b.AddInterceptors(CurrentInterceptor);
+        return b;
+    }
+
+    protected override void OnModelCreating(ModelBuilder b, DbContext ctx)
+    {
+        b.Entity<ItemDefault>(e => e.HasKey(x => x.Id));
+
+        b.Entity<ItemExplicit>(e =>
+        {
+            e.HasKey(x => x.Id);
+            e.Property(x => x.Price).HasPrecision(22, 9);
+        });
+    }
+
+    public class DecimalContext(DbContextOptions options) : DbContext(options);
+}
+
+public class ItemDefault { public int Id { get; init; } public decimal Price { get; init; } }
+public class ItemExplicit { public int Id { get; init; } public decimal Price { get; init; } }

src/EFCore.Ydb/test/EntityFrameworkCore.Ydb.FunctionalTests/Query/DecimalParameterYdbTest.cs

@@ -0,0 +1,53 @@
+using Microsoft.EntityFrameworkCore;
+using Xunit;
+
+namespace EntityFrameworkCore.Ydb.FunctionalTests.Query;
+
+public class DecimalParameterYdbTest(DecimalParameterQueryYdbFixture fixture)
+    : IClassFixture<DecimalParameterQueryYdbFixture>
+{
+    private DecimalParameterQueryYdbFixture Fixture { get; } = fixture;
+
+    [ConditionalFact]
+    public async Task Parameter_decimal_uses_default_22_9_and_roundtrips()
+    {
+        await using var ctx = Fixture.CreateContext();
+        await ctx.Database.EnsureCreatedAsync();
+
+        decimal v = 1.23456789m;
+        ctx.Add(new ItemDefault { Price = v });
+        await ctx.SaveChangesAsync();
+
+        var got = await ctx.Set<ItemDefault>().Where(x => x.Price == v).ToListAsync();
+        Assert.Single(got);
+        Assert.Equal(v, got[0].Price);
+    }
+
+    [ConditionalFact]
+    public async Task Parameter_decimal_respects_explicit_22_9_and_roundtrips()
+    {
+        await using var ctx = Fixture.CreateContext();
+        await ctx.Database.EnsureCreatedAsync();
+
+        decimal v = 123.456789012m;
+        ctx.Add(new ItemExplicit { Price = v });
+        await ctx.SaveChangesAsync();
+
+        var got = await ctx.Set<ItemExplicit>().Where(x => x.Price == v).ToListAsync();
+        Assert.Single(got);
+        Assert.Equal(v, got[0].Price);
+    }
+    
+    [ConditionalFact]
+    public async Task Decimal_out_of_range_bubbles_up()
+    {
+        await using var ctx = Fixture.CreateContext();
+        await ctx.Database.EnsureCreatedAsync();
+
+        var tooBig = new ItemExplicit { Price = 10_000_000_000_000m }; // 14 целых цифр -> вне 22,9
+        ctx.Add(tooBig);
+
+        var ex = await Assert.ThrowsAsync<DbUpdateException>(() => ctx.SaveChangesAsync());
+        Assert.Contains("Decimal", ex.InnerException?.Message ?? "");
+    }
+}