radzen-blazor/Radzen.Blazor.Tests/LocalizerTests.cs

using System.Collections.Generic;
using System.Globalization;
using Bunit;
using Microsoft.AspNetCore.Components;
using Microsoft.Extensions.DependencyInjection;
using Radzen;
using Radzen.Blazor;
using Xunit;

#nullable enable
namespace Radzen.Blazor.Tests;

public class LocalizerTests
{
    [Fact]
    public void Localizer_Returns_Resx_Default()
    {
        var result = Localizer.Default.Get(nameof(RadzenStrings.Spreadsheet_OK), CultureInfo.InvariantCulture);

        Assert.Equal("OK", result);
    }

    [Fact]
    public void Localizer_Returns_Key_When_Not_Found()
    {
        var result = Localizer.Default.Get("NonExistent_Key", CultureInfo.InvariantCulture);

        Assert.Equal("NonExistent_Key", result);
    }

    [Fact]
    public void Localizer_Custom_Override_Takes_Precedence()
    {
        var custom = new TestLocalizer("Spreadsheet_OK", "Aceptar");
        var localizer = new Localizer(custom);

        var result = localizer.Get(nameof(RadzenStrings.Spreadsheet_OK), CultureInfo.InvariantCulture);

        Assert.Equal("Aceptar", result);
    }

    [Fact]
    public void Localizer_Custom_Returns_Null_Falls_Back_To_Resx()
    {
        var custom = new TestLocalizer("other_key", "other_value");
        var localizer = new Localizer(custom);

        var result = localizer.Get(nameof(RadzenStrings.Spreadsheet_OK), CultureInfo.InvariantCulture);

        Assert.Equal("OK", result);
    }

    [Fact]
    public void Localizer_Returns_Resx_Default_For_Various_Keys()
    {
        var localizer = Localizer.Default;

        Assert.Equal("Sort ascending", localizer.Get(nameof(RadzenStrings.Spreadsheet_SortAscending), CultureInfo.InvariantCulture));
        Assert.Equal("Cancel", localizer.Get(nameof(RadzenStrings.Spreadsheet_Cancel), CultureInfo.InvariantCulture));
        Assert.Equal("contains", localizer.Get(nameof(RadzenStrings.Spreadsheet_FilterContains), CultureInfo.InvariantCulture));
        Assert.Equal("Format Cells...", localizer.Get(nameof(RadzenStrings.Spreadsheet_FormatCells), CultureInfo.InvariantCulture));
    }

    [Fact]
    public void AddRadzenComponents_Registers_Localizer()
    {
        var services = new ServiceCollection();
        services.AddRadzenComponents();
        var provider = services.BuildServiceProvider();

        var localizer = provider.GetService<Localizer>();

        Assert.NotNull(localizer);
    }

    [Fact]
    public void Localizer_Works_Without_ILocalizer_Registered()
    {
        var services = new ServiceCollection();
        services.AddRadzenComponents();
        var provider = services.BuildServiceProvider();

        var localizer = provider.GetRequiredService<Localizer>();
        var result = localizer.Get(nameof(RadzenStrings.Spreadsheet_OK), CultureInfo.InvariantCulture);

        Assert.Equal("OK", result);
    }

    [Fact]
    public void Localizer_Uses_Custom_ILocalizer_When_Registered()
    {
        var services = new ServiceCollection();
        services.AddRadzenComponents();
        services.AddSingleton<ILocalizer>(new TestLocalizer("Spreadsheet_OK", "Aceptar"));
        var provider = services.BuildServiceProvider();

        var localizer = provider.GetRequiredService<Localizer>();
        var result = localizer.Get(nameof(RadzenStrings.Spreadsheet_OK), CultureInfo.InvariantCulture);

        Assert.Equal("Aceptar", result);
    }

    [Fact]
    public void Localizer_Format_String_Key_Contains_Placeholder()
    {
        var localizer = Localizer.Default;
        var template = localizer.Get(nameof(RadzenStrings.Spreadsheet_SheetNameAlreadyExists), CultureInfo.InvariantCulture);
        var result = string.Format(template, "Sheet2");

        Assert.Equal("A sheet named 'Sheet2' already exists.", result);
    }

    [Theory]
    [InlineData("de")]
    [InlineData("fr")]
    [InlineData("es")]
    [InlineData("it")]
    [InlineData("ja")]
    public void Localizer_Resolves_Builtin_Translations_For_Culture(string lang)
    {
        var culture = new CultureInfo(lang);

        var cancel = Localizer.Default.Get(nameof(RadzenStrings.Spreadsheet_Cancel), culture);

        // The built-in satellite resource must resolve and translate Cancel away from English.
        Assert.NotEqual("Cancel", cancel);
        Assert.False(string.IsNullOrWhiteSpace(cancel));
    }

    [Fact]
    public void Localizer_Translates_Known_Strings()
    {
        Assert.Equal("Abbrechen", Localizer.Default.Get(nameof(RadzenStrings.Spreadsheet_Cancel), new CultureInfo("de")));
        Assert.Equal("Aujourd'hui", Localizer.Default.Get(nameof(RadzenStrings.Scheduler_TodayText), new CultureInfo("fr")));
        Assert.Equal("キャンセル", Localizer.Default.Get(nameof(RadzenStrings.Spreadsheet_Cancel), new CultureInfo("ja")));
    }

    [Fact]
    public void DataGrid_Uses_DefaultUICulture_Cascade_For_Localized_Strings()
    {
        using var ctx = new TestContext();
        ctx.JSInterop.Mode = JSRuntimeMode.Loose;
        ctx.JSInterop.SetupModule("_content/Radzen.Blazor/Radzen.Blazor.js");
        ctx.Services.AddRadzenComponents();

        var component = ctx.RenderComponent<CascadingValue<CultureInfo>>(parameters => parameters
            .Add(p => p.Name, nameof(RadzenComponent.DefaultUICulture))
            .Add(p => p.Value, new CultureInfo("de"))
            .AddChildContent<RadzenDataGrid<dynamic>>(grid => grid
                .Add(g => g.Data, (IEnumerable<dynamic>)new[] { new { Id = 1 } })
                .Add(g => g.AllowGrouping, true)));

        // German translation of DataGrid_GroupPanelText must appear via the cascade + satellite resource.
        Assert.Contains("Ziehen Sie eine Spaltenüberschrift", component.Markup);
        Assert.DoesNotContain("Drag a column header here", component.Markup);
    }

    private class TestLocalizer : ILocalizer
    {
        private readonly string key;
        private readonly string value;

        public TestLocalizer(string key, string value)
        {
            this.key = key;
            this.value = value;
        }

        public string? Get(string key, CultureInfo culture)
        {
            return key == this.key ? value : null;
        }
    }
}