Phase 0 (T1-3/4/7/9/11): find bar w/ native Find API + search engine + site zoom + force reload + F11, wired into MainWindow, E2E smoke (39 tests)

VideoDownloader.Tests/Browser/FindSessionTests.cs

@@ -0,0 +1,98 @@
+using VideoDownloader.App.Browser;
+
+namespace VideoDownloader.Tests.Browser;
+
+// T1-3 페이지 내 검색: FindSession 은 네이티브 Find API(IFindApi) 위의 상태 머신.
+public class FindSessionTests
+{
+    private sealed class FakeFindApi : IFindApi
+    {
+        public string? LastTerm;
+        public int StartCount, NextCount, PrevCount, StopCount;
+        public int MatchCount { get; set; }
+        public int ActiveIndex { get; set; }
+
+        public event EventHandler<int>? MatchCountChanged;
+        public event EventHandler<int>? ActiveMatchIndexChanged;
+
+        public Task StartAsync(string term, bool caseSensitive, bool matchWord, bool highlightAll)
+        {
+            StartCount++; LastTerm = term; return Task.CompletedTask;
+        }
+        public void FindNext() => NextCount++;
+        public void FindPrevious() => PrevCount++;
+        public void Stop() => StopCount++;
+
+        public void RaiseCount(int n) { MatchCount = n; MatchCountChanged?.Invoke(this, n); }
+        public void RaiseActive(int n) { ActiveIndex = n; ActiveMatchIndexChanged?.Invoke(this, n); }
+    }
+
+    [Fact]
+    public void Start는_API로_용어를_전달하고_카운트_이벤트를_구독_반영한다()
+    {
+        var api = new FakeFindApi();
+        var session = new FindSession(api);
+
+        session.StartAsync("hello").Wait();
+        api.RaiseCount(7);
+
+        Assert.Equal(1, api.StartCount);
+        Assert.Equal("hello", api.LastTerm);
+        Assert.Equal(7, session.MatchCount);
+    }
+
+    [Fact]
+    public void Next_Previous는_API에_위임한다()
+    {
+        var api = new FakeFindApi();
+        var session = new FindSession(api);
+        session.StartAsync("x").Wait();
+
+        session.Next();
+        session.Previous();
+
+        Assert.Equal(1, api.NextCount);
+        Assert.Equal(1, api.PrevCount);
+    }
+
+    [Fact]
+    public void ActiveMatchIndex_이벤트가_상태에_반영된다()
+    {
+        var api = new FakeFindApi();
+        var session = new FindSession(api);
+        session.StartAsync("x").Wait();
+
+        api.RaiseActive(3);
+        Assert.Equal(3, session.ActiveMatchIndex);
+    }
+
+    [Fact]
+    public void 빈_용어로_Start하면_Stop만_호출된다()
+    {
+        var api = new FakeFindApi();
+        var session = new FindSession(api);
+
+        session.StartAsync("   ").Wait();
+
+        Assert.Equal(0, api.StartCount);
+        Assert.Equal(1, api.StopCount);
+        Assert.Equal(0, session.MatchCount);
+    }
+
+    [Fact]
+    public void Close는_Stop을_호출하고_상태를_초기화한다()
+    {
+        var api = new FakeFindApi();
+        var session = new FindSession(api);
+        session.StartAsync("x").Wait();
+        api.RaiseCount(5);
+        api.RaiseActive(2);
+
+        session.Close();
+
+        Assert.Equal(1, api.StopCount);
+        Assert.Equal(0, session.MatchCount);
+        Assert.Equal(-1, session.ActiveMatchIndex); // -1 = 활성 매치 없음(Start 초기값과 동일 센티넬)
+        Assert.Equal(string.Empty, session.Term);
+    }
+}