fix #1711 (#1716)

* fix #1711

* fix for net462 build

Author: jonsequitur

src/System.CommandLine.Tests/ParserTests.MultipleArguments.cs

@@ -2,8 +2,9 @@
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
 using System.Collections.Generic;
+using System.CommandLine.Parsing;
 using System.CommandLine.Tests.Utility;
-using System.Threading.Tasks;
+using System.Linq;
 using FluentAssertions;
 using FluentAssertions.Execution;
 using Xunit;
@@ -149,17 +150,12 @@ public void Multiple_arguments_of_unspecified_type_are_parsed_correctly()
             public void When_multiple_arguments_are_defined_but_not_provided_then_option_parses_correctly()
             {
                 var option = new Option<string>("-e");
-                var command = new Command("the-command") { option };
-
-                command.AddArgument(new Argument<string>
-                {
-                    Name = "arg1",
-                });
-
-                command.AddArgument(new Argument<string>
+                var command = new Command("the-command")
                 {
-                    Name = "arg2",
-                });
+                    option,
+                    new Argument<string>(),
+                    new Argument<string>()
+                };
 
                 var result = command.Parse("-e foo");
 
@@ -168,9 +164,8 @@ public void When_multiple_arguments_are_defined_but_not_provided_then_option_par
                 optionResult.Should().Be("foo");
             }
 
-
             [Fact]
-            public void tokens_that_cannot_be_converted_by_multiple_arity_argument_flow_to_next_multiple_arity_argument()
+            public void Tokens_that_cannot_be_converted_by_multiple_arity_argument_flow_to_next_multiple_arity_argument()
             {
                 var ints = new Argument<int[]>();
                 var strings = new Argument<string[]>();
@@ -197,7 +192,7 @@ public void tokens_that_cannot_be_converted_by_multiple_arity_argument_flow_to_n
             }
 
             [Fact]
-            public void tokens_that_cannot_be_converted_by_multiple_arity_argument_flow_to_next_single_arity_argument()
+            public void Tokens_that_cannot_be_converted_by_multiple_arity_argument_flow_to_next_single_arity_argument()
             {
                 var ints = new Argument<int[]>();
                 var strings = new Argument<string>();
@@ -232,11 +227,11 @@ public void tokens_that_cannot_be_converted_by_multiple_arity_argument_flow_to_n
             [Fact]
             public void Unsatisfied_subsequent_argument_with_min_arity_0_parses_as_default_value()
             {
-                var arg1 = new Argument<string>("arg1")
+                var arg1 = new Argument<string>
                 {
                     Arity = ArgumentArity.ExactlyOne
                 };
-                var arg2 = new Argument<string>("arg2")
+                var arg2 = new Argument<string>
                 {
                     Arity = ArgumentArity.ZeroOrOne,
                 };
@@ -290,6 +285,34 @@ public void When_subsequent_argument_with_ZeroOrOne_arity_is_not_provided_then_p
 
                 result.GetValueForArgument(argument1).Should().Be("one");
             }
+
+            [Theory] // https://github.com/dotnet/command-line-api/issues/1711
+            [InlineData("")]
+            [InlineData("a")]
+            [InlineData("a b")]
+            [InlineData("a b c")]
+            public void When_there_are_not_enough_tokens_for_all_arguments_then_the_correct_number_of_errors_is_reported(
+                string providedArgs)
+            {
+                var command = new Command("command")
+                {
+                    new Argument<string>(),
+                    new Argument<string>(),
+                    new Argument<string>(),
+                    new Argument<string>()
+                };
+
+                var result = new Parser(command).Parse(providedArgs);
+
+                var numberOfMissingArgs =
+                    result
+                        .Errors
+                        .Count(e => e.Message == LocalizationResources.Instance.RequiredArgumentMissing(result.CommandResult));
+
+                numberOfMissingArgs
+                    .Should()
+                    .Be(4 - providedArgs.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).Length);
+            }
         }
     }
 }

src/System.CommandLine.Tests/ParserTests.cs

@@ -16,9 +16,7 @@
 namespace System.CommandLine.Tests
 {
     public partial class ParserTests
-    {public partial class RootCommandAndArg0
-        {
-        }
+    {
         private readonly ITestOutputHelper _output;
 
         public ParserTests(ITestOutputHelper output)

src/System.CommandLine/Parsing/ParseResultVisitor.cs

@@ -291,21 +291,24 @@ private void ValidateAndConvertArgumentResults(IReadOnlyList<Argument> arguments
                     _symbolResults.TryAdd(nextArgumentResult.Symbol, nextArgumentResult);
                 }
 
-                var argumentResult = _argumentResults[i];
+                if (commandArgumentResultCount >= _argumentResults.Count)
+                {
+                    var argumentResult = _argumentResults[i];
 
-                ValidateAndConvertArgumentResult(argumentResult);
+                    ValidateAndConvertArgumentResult(argumentResult);
 
-                if (argumentResult.PassedOnTokens is { } &&
-                    i == arguments.Count - 1)
-                {
-                    _unparsedTokens ??= new List<Token>();
-                    _unparsedTokens.AddRange(argumentResult.PassedOnTokens);
+                    if (argumentResult.PassedOnTokens is { } &&
+                        i == arguments.Count - 1)
+                    {
+                        _unparsedTokens ??= new List<Token>();
+                        _unparsedTokens.AddRange(argumentResult.PassedOnTokens);
+                    }
                 }
             }
 
             if (_argumentResults.Count > arguments.Count)
             {
-                for (var i = arguments.Count; i < _argumentResults.Count; i++)
+                for (var i = arguments.Count; i < _argumentResults.Count - 1; i++)
                 {
                     var result = _argumentResults[i];
 

src/System.CommandLine/Parsing/SymbolResultExtensions.cs

@@ -25,7 +25,7 @@ internal static Token Token(this SymbolResult symbolResult)
             return symbolResult switch
             {
                 CommandResult commandResult => commandResult.Token,
-                OptionResult optionResult => optionResult.Token is null ? CreateImplicitToken(optionResult.Option) : optionResult.Token,
+                OptionResult optionResult => optionResult.Token ?? CreateImplicitToken(optionResult.Option),
                 _ => throw new ArgumentOutOfRangeException(nameof(symbolResult))
             };