Do not show suggestions in help if too long

Author: sfoslund

src/System.CommandLine.Tests/Help/HelpBuilderTests.cs

@@ -469,6 +469,38 @@ public void Arguments_section_includes_configured_argument_aliases()
             help.Should().Contain("Sets the verbosity.");
         }
 
+
+        private enum VerbosityOptions
+        {
+            quiet,
+            q,
+            minimal,
+            m,
+            normal,
+            n,
+            detailed,
+            d,
+            diagnostic,
+            diag
+        }
+
+        [Fact]
+        public void Arguments_section_uses_name_if_suggestions_are_long()
+        {
+            var command = new Command("the-command")
+            {
+                new Option<VerbosityOptions>(new[] { "-v", "--verbosity" })
+                {
+                    ArgumentHelpName = "LEVEL"
+                }
+            };
+
+            _helpBuilder.Write(command);
+
+            var help = _console.Out.ToString();
+            help.Should().Contain("-v, --verbosity <LEVEL>");
+        }
+
         [Fact]
         public void Arguments_section_uses_description_if_provided()
         {
@@ -1240,7 +1272,7 @@ public void Help_describes_default_value_for_option_with_argument_having_default
 
             help.Should().Contain($"[default: the-arg-value]");
         }
-
+        
         [Fact]
         public void Option_arguments_with_default_values_that_are_enumerable_display_pipe_delimited_list()
         {

src/System.CommandLine/Help/HelpBuilder.cs

@@ -522,7 +522,7 @@ protected string GetArgumentDescriptor(IArgument argument)
 
             string descriptor;
             var suggestions = argument.GetSuggestions().ToArray();
-            if (suggestions.Length > 0)
+            if (suggestions.Length > 0 && string.Join("|", suggestions).Length < 50)
             {
                 descriptor = string.Join("|", suggestions);
             }