Add Open in Notepad++ and static Windows shell verbs without embedding IContextMenu on right-click.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/Explorer.Application.Tests/NotepadPlusPlusLocatorTests.cs

@@ -0,0 +1,22 @@
+using Explorer.Application;
+
+namespace Explorer.Application.Tests;
+
+public class NotepadPlusPlusLocatorTests
+{
+    [Fact]
+    public void Finds_notepad_plus_plus_on_PATH()
+    {
+        var found = NotepadPlusPlusLocator.Find(
+            fileExists: p => p.Equals(@"D:\apps\notepad++.exe", StringComparison.OrdinalIgnoreCase),
+            pathVariable: @"C:\Windows;D:\apps");
+        Assert.Equal(@"D:\apps\notepad++.exe", found);
+    }
+
+    [Fact]
+    public void Returns_null_when_missing()
+    {
+        Assert.Null(NotepadPlusPlusLocator.Find(fileExists: _ => false, pathVariable: @"C:\none"));
+        Assert.Contains("Notepad++", NotepadPlusPlusLocator.MissingHint, StringComparison.OrdinalIgnoreCase);
+    }
+}

tests/Explorer.Application.Tests/ShellContextVerbFilterTests.cs

@@ -0,0 +1,75 @@
+using Explorer.Application;
+using Explorer.Domain.Abstractions;
+
+namespace Explorer.Application.Tests;
+
+public class ShellContextVerbFilterTests
+{
+    [Fact]
+    public void Keeps_third_party_open_with_and_hides_workbench_duplicates()
+    {
+        Assert.True(ShellContextVerbFilter.ShouldInclude("Open with Notepad++", "Open with &Notepad++"));
+        Assert.True(ShellContextVerbFilter.ShouldInclude("edit", "Edit"));
+        Assert.True(ShellContextVerbFilter.ShouldInclude("openas", "Open with"));
+        Assert.False(ShellContextVerbFilter.ShouldInclude("open", "Open"));
+        Assert.False(ShellContextVerbFilter.ShouldInclude("cut", "Cu&t"));
+        Assert.False(ShellContextVerbFilter.ShouldInclude("properties", "P&roperties"));
+        Assert.False(ShellContextVerbFilter.ShouldInclude(null, "Open in Cursor"));
+        Assert.False(ShellContextVerbFilter.ShouldInclude(null, "Open in Notepad++"));
+        Assert.False(ShellContextVerbFilter.ShouldInclude(null, "Edit with Notepad++"));
+        Assert.Equal("Open with Notepad++", ShellContextVerbFilter.CanonicalLabel("Open with &Notepad++"));
+    }
+
+    [Fact]
+    public void Prune_drops_empty_submenus_and_builtin_rows()
+    {
+        var items = new[]
+        {
+            new ShellContextVerb("verb:open", "Open"),
+            new ShellContextVerb("verb:npp", "Open with &Notepad++"),
+            new ShellContextVerb("verb:zip", "7-Zip", [
+                new ShellContextVerb("verb:zip.add", "Add to archive…")
+            ]),
+            new ShellContextVerb("verb:empty", "Empty", [])
+        };
+        var pruned = ShellContextVerbFilter.Prune(items);
+        Assert.Equal(2, pruned.Count);
+        Assert.Equal("Open with &Notepad++", pruned[0].Label);
+        Assert.Equal("7-Zip", pruned[1].Label);
+        Assert.Single(pruned[1].Children!);
+    }
+
+    [Fact]
+    public void MergeByLabel_adds_missing_third_party_verbs()
+    {
+        var merged = ShellContextVerbFilter.MergeByLabel(
+            [new ShellContextVerb("cmd:1", "PDF24")],
+            [new ShellContextVerb("static:0", "Open with &Notepad++"), new ShellContextVerb("cmd:2", "PDF24")]);
+        Assert.Equal(2, merged.Count);
+        Assert.Equal("PDF24", merged[0].Label);
+        Assert.Equal("Open with &Notepad++", merged[1].Label);
+    }
+
+    [Fact]
+    public void Command_split_and_expand_runs_once_per_file_for_percent_one()
+    {
+        Assert.True(ShellVerbCommand.TrySplit(
+            @"""C:\Program Files\Notepad++\notepad++.exe"" ""%1""",
+            out var exe,
+            out var args));
+        Assert.Equal(@"C:\Program Files\Notepad++\notepad++.exe", exe);
+        var invocations = ShellVerbCommand.ExpandInvocations(args, [@"C:\a.txt", @"C:\b c.txt"]);
+        Assert.Equal(2, invocations.Count);
+        Assert.Equal(@"""C:\a.txt""", invocations[0].Trim());
+        Assert.Contains(@"C:\b c.txt", invocations[1], StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void Percent_star_keeps_one_invocation()
+    {
+        var invocations = ShellVerbCommand.ExpandInvocations("%*", [@"C:\a.txt", @"C:\b.txt"]);
+        Assert.Single(invocations);
+        Assert.Contains(@"C:\a.txt", invocations[0], StringComparison.Ordinal);
+        Assert.Contains(@"C:\b.txt", invocations[0], StringComparison.Ordinal);
+    }
+}