remove ISymbol, IArgument, IIdentifierSymbol, IOption and ICommand interfaces (#1538)

* remove ISymbol, IArgument, IIdentifierSymbol, IOption and ICommand interfaces

each of them had a single implementation and it was increasing the amount of types required to be JITted

* remove redundant casts (perf)

Author: adamsitnik

src/System.CommandLine.ApiCompatibility.Tests/ApiCompatibilityApprovalTests.System_CommandLine_api_is_not_changed.approved.txt

@@ -55,7 +55,7 @@ public void SetupRootCommand()
             GenerateTestNestedCommands(rootCommand, TestCommandsDepth, TestCommandsDepth);
 
             // Choose only one path from the commands tree for the test arguments string
-            ISymbol currentCmd = rootCommand;
+            Symbol currentCmd = rootCommand;
             while (currentCmd.Children.Count > 0)
             {
                 currentCmd = currentCmd.Children[0];

src/System.CommandLine.Benchmarks/CommandLine/Perf_Parser_NestedCommands.cs

@@ -18,7 +18,7 @@ public static class CommandExtensions
     public static void SetHandler<TDelegate>(
         this Command command,
         TDelegate @delegate,
-        params ISymbol[] symbols)
+        params Symbol[] symbols)
     {
         throw new InvalidOperationException(_messageForWhenGeneratorIsNotInUse);
     }

src/System.CommandLine.Generator.CommandHandler/CommandExtensions.cs

@@ -135,7 +135,7 @@ private bool ShortCutTheBinding()
                                                    bindingContext.ParseResult.CommandResult.LocalizationResources,
                                                    out var boundValue)
                    ? (true, boundValue?.Value, true)
-                   : (false,(object?) null, false);
+                   : (false, null, false);
     }
 
     private (bool success, object? newInstance, bool anyNonDefaults) InstanceFromSpecificConstructor(

src/System.CommandLine.NamingConventionBinder/ModelBinder.cs

@@ -21,15 +21,15 @@ public bool TryGetValue(IValueDescriptor valueDescriptor,
         var specificDescriptor = ValueDescriptor;
         switch (specificDescriptor)
         {
-            case IOption option:
+            case Option option:
                 var optionResult = bindingContext?.ParseResult.FindResultFor(option);
                 if (optionResult is not null)
                 {
                     boundValue = optionResult.GetValueOrDefault();
                     return true;
                 }
                 break;
-            case IArgument argument:
+            case Argument argument:
                 var argumentResult = bindingContext?.ParseResult.FindResultFor(argument);
                 if (argumentResult is not null)
                 {

src/System.CommandLine.NamingConventionBinder/SpecificSymbolValueSource.cs

@@ -215,7 +215,7 @@ public void Commands_can_have_aliases()
 
             var result = command.Parse("that");
 
-            result.CommandResult.Command.Should().Be(command);
+            result.CommandResult.Command.Should().BeSameAs(command);
             result.Errors.Should().BeEmpty();
         }
 
@@ -229,7 +229,7 @@ public void RootCommand_can_have_aliases()
 
             var result = command.Parse("that");
 
-            result.CommandResult.Command.Should().Be(command);
+            result.CommandResult.Command.Should().BeSameAs(command);
             result.Errors.Should().BeEmpty();
         }
 
@@ -246,7 +246,7 @@ public void Subcommands_can_have_aliases()
 
             var result = rootCommand.Parse("that");
 
-            result.CommandResult.Command.Should().Be(subcommand);
+            result.CommandResult.Command.Should().BeSameAs(subcommand);
             result.Errors.Should().BeEmpty();
         }
 

src/System.CommandLine.Tests/CommandTests.cs

@@ -10,7 +10,7 @@ public static class HelpBuilderExtensions
     {
         public static void Write(
             this HelpBuilder builder,
-            ICommand command,
+            Command command,
             TextWriter writer) =>
             builder.Write(new HelpContext(builder, command, writer));
     }

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

@@ -838,8 +838,8 @@ public void A_renamed_RootCommand_can_be_omitted_from_the_parsed_args()
             var result2 = rootCommand.Parse("outer inner -x hello");
             var result3 = rootCommand.Parse($"{RootCommand.ExecutableName} inner -x hello");
 
-            result2.RootCommandResult.Command.Should().Be(result1.RootCommandResult.Command);
-            result3.RootCommandResult.Command.Should().Be(result1.RootCommandResult.Command);
+            result2.RootCommandResult.Command.Should().BeSameAs(result1.RootCommandResult.Command);
+            result3.RootCommandResult.Command.Should().BeSameAs(result1.RootCommandResult.Command);
         }
 
         [Fact]
@@ -1069,19 +1069,19 @@ public void Option_and_Command_can_have_the_same_alias()
                   .CommandResult
                   .Command
                   .Should()
-                  .Be(innerCommand);
+                  .BeSameAs(innerCommand);
 
             parser.Parse("outer --inner")
                   .CommandResult
                   .Command
                   .Should()
-                  .Be(outerCommand);
+                  .BeSameAs(outerCommand);
 
             parser.Parse("outer --inner inner")
                   .CommandResult
                   .Command
                   .Should()
-                  .Be(innerCommand);
+                  .BeSameAs(innerCommand);
 
             parser.Parse("outer --inner inner")
                   .CommandResult
@@ -1218,7 +1218,7 @@ public void Option_arguments_can_match_subcommands()
             _output.WriteLine(result.ToString());
 
             result.GetValueForOption(optionA).Should().Be("subcommand");
-            result.CommandResult.Command.Should().Be(root);
+            result.CommandResult.Command.Should().BeSameAs(root);
         }
 
         [Fact]
@@ -1236,7 +1236,7 @@ public void Arguments_can_match_subcommands()
 
             var result = root.Parse("subcommand one two three subcommand four");
 
-            result.CommandResult.Command.Should().Be(subcommand);
+            result.CommandResult.Command.Should().BeSameAs(subcommand);
 
             result.GetValueForArgument(argument)
                   .Should()
@@ -1681,7 +1681,7 @@ public void Empty_strings_in_parsed_args_array_are_ignored()
 
             result.Errors.Should().BeEmpty();
 
-            result.CommandResult.Command.Should().Be(subcommand);
+            result.CommandResult.Command.Should().BeSameAs(subcommand);
             result.FindResultFor(option).Should().NotBeNull();
         }
 

src/System.CommandLine.Tests/ParserTests.cs

@@ -915,7 +915,7 @@ public void A_command_with_subcommands_is_valid_to_invoke_if_it_has_a_handler()
             var result = outer.Parse("outer inner");
 
             result.Errors.Should().BeEmpty();
-            result.CommandResult.Command.Should().Be(inner);
+            result.CommandResult.Command.Should().BeSameAs(inner);
         }
 
         [Fact]

src/System.CommandLine.Tests/ParsingValidationTests.cs

@@ -8,7 +8,7 @@ namespace System.CommandLine.Tests
 {
     internal static class SymbolSetExtensions
     {
-        internal static ISymbol GetByAlias(this SymbolSet symbolSet, string alias)
+        internal static Symbol GetByAlias(this SymbolSet symbolSet, string alias)
             => symbolSet.SingleOrDefault(symbol => symbol.Name.Equals(alias) || symbol is IdentifierSymbol id && id.HasAlias(alias));
 
         internal static bool ContainsAlias(this SymbolSet symbolSet, string alias)