Parent search bug fix (#2030)

Author: adamsitnik

src/System.CommandLine.Tests/CompletionTests.cs

@@ -57,20 +57,25 @@ public void Command_GetCompletions_returns_available_option_aliases()
         [Fact] // https://github.com/dotnet/command-line-api/issues/1563
         public void Command_GetCompletions_returns_available_option_aliases_for_global_options()
         {
-            var subcommand = new Command("command")
+            var subcommand2 = new Command("command2")
             {
                 new Option<string>("--one", "option one"),
                 new Option<string>("--two", "option two")
             };
 
+            var subcommand1 = new Command("command1")
+            {
+                subcommand2
+            };
+
             var rootCommand = new RootCommand
             {
-                subcommand
+                subcommand1
             };
 
             rootCommand.AddGlobalOption(new Option<string>("--three", "option three"));
 
-            var completions = subcommand.GetCompletions(CompletionContext.Empty);
+            var completions = subcommand2.GetCompletions(CompletionContext.Empty);
 
             completions
                 .Select(item => item.Label)

src/System.CommandLine.Tests/ParseResultTests.cs

@@ -1,6 +1,7 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+using System.Linq;
 using System.CommandLine.Parsing;
 using FluentAssertions;
 using Xunit;
@@ -83,5 +84,42 @@ public void Command_will_not_accept_a_command_if_a_sibling_command_has_already_b
             result2.CommandResult.Command.Name.Should().Be("inner-two");
             result2.Errors.Count.Should().Be(1);
         }
+
+        [Fact] // https://github.com/dotnet/command-line-api/pull/2030#issuecomment-1400275332
+        public void ParseResult_GetCompletions_returns_global_options_of_given_command_only()
+        {
+            var leafCommand = new Command("leafCommand")
+            {
+                new Option<string>("--one", "option one"),
+                new Option<string>("--two", "option two")
+            };
+
+            var midCommand1 = new Command("midCommand1")
+            {
+                leafCommand
+            };
+            midCommand1.AddGlobalOption(new Option<string>("--three1", "option three 1"));
+
+            var midCommand2 = new Command("midCommand2")
+            {
+                leafCommand
+            };
+            midCommand2.AddGlobalOption(new Option<string>("--three2", "option three 2"));
+
+            var rootCommand = new Command("root")
+            {
+                midCommand1,
+                midCommand2
+            };
+
+            var result = new Parser(rootCommand).Parse("root midCommand2 leafCommand --");
+
+            var completions = result.GetCompletions();
+
+            completions
+                .Select(item => item.Label)
+                .Should()
+                .BeEquivalentTo("--one", "--two", "--three2");
+        }
     }
 }

src/System.CommandLine/Command.cs

@@ -192,20 +192,28 @@ public override IEnumerable<CompletionItem> GetCompletions(CompletionContext con
                 ParentNode? parent = FirstParent;
                 while (parent is not null)
                 {
-                    if (parent.Symbol is Command parentCommand && parentCommand.HasOptions)
+                    Command parentCommand = (Command)parent.Symbol;
+
+                    if (context.IsEmpty || context.ParseResult.FindResultFor(parentCommand) is not null)
                     {
-                        for (var i = 0; i < parentCommand.Options.Count; i++)
+                        if (parentCommand.HasOptions)
                         {
-                            var option = parentCommand.Options[i];
-
-                            if (option.IsGlobal)
+                            for (var i = 0; i < parentCommand.Options.Count; i++)
                             {
-                                AddCompletionsFor(option);
+                                var option = parentCommand.Options[i];
+
+                                if (option.IsGlobal)
+                                {
+                                    AddCompletionsFor(option);
+                                }
                             }
                         }
+                        parent = parent.Symbol.FirstParent;
+                    }
+                    else
+                    {
+                        parent = parent.Next;
                     }
-
-                    parent = parent.Next;
                 }
             }
 

src/System.CommandLine/Completions/CompletionContext.cs

@@ -31,6 +31,8 @@ internal CompletionContext(ParseResult parseResult, string wordToComplete)
         /// <remarks>Can be used for testing purposes.</remarks>
         public static CompletionContext Empty => _empty ??= new TokenCompletionContext(ParseResult.Empty());
 
+        internal bool IsEmpty => ReferenceEquals(this, _empty);
+
         /// <summary>
         /// Gets the text to be matched for completion, which can be used to filter a list of completions.
         /// </summary>