Stop parsing option (#98)

* Add stop processing option fixes #92

Author: Matthiee

CommandLineParser.Tests/CommandLineParserTests.cs

@@ -113,6 +113,25 @@ public void OrderedOptions_With_Named_Option_Between_Does_Not_work2()
             Assert.NotEqual(to, result.Result.To);
         }
 
+        [Fact]
+        public void StopProcessingWorks()
+        {
+            var options = new CommandLineParserOptions 
+            {
+                StopParsingAfter = "--"
+            };
+
+            var parser = new CommandLineParser<OrderModelInt>(options, Services);
+
+            var result = parser.Parse(new string[] { "app.exe", "10", "20", "--", "some random stuff", "nothing to see here", "yadi yadi yadi", "-r", "10" });
+
+            result.AssertNoErrors();
+
+            Assert.Equal(10, result.Result.From);
+            Assert.Equal(20, result.Result.To);
+            Assert.NotEqual(10, result.Result.Random);
+        }
+
         [Theory]
         [InlineData("", "--")]
         [InlineData("-", "")]

CommandLineParser/CommandLineParser.xml

@@ -22,6 +22,11 @@ public class CommandLineParserOptions
         /// </summary>
         public string PostfixOption { get; set; } = "=";
 
+        /// <summary>
+        /// Stops parsing of remaining arguments after this has been found
+        /// </summary>
+        public string StopParsingAfter { get; set; }
+
         /// <summary>
         /// Help option name. 
         /// Accepts both formatted and unformatted help name. 

CommandLineParser/CommandLineParserOptions.cs

@@ -82,11 +82,23 @@ private bool ProcessNext()
                     return ProcessOption(option);
                 case CommandOrOptionValueRecord commandOrValue:
                     return ProcessCommandOrOptionValue(commandOrValue);
+                case StopProcessingRecord _:
+                    return StopProcessing();
                 default:
                     return false;
             }
         }
 
+        private bool StopProcessing()
+        {
+            while (enumerator.MoveNext())
+            { 
+                // do nothing
+            }
+
+            return true;
+        }
+
         private void AddUnprocessedArgument(ArgumentRecord rec)
         {
             var arg = CurrentContext.CurrentOption != null ? (IArgument)CurrentContext.CurrentOption : (IArgument)CurrentContext.CurrentCommand;
@@ -403,6 +415,12 @@ private ArgumentRecord CreateRecord(string current)
             {
                 bool isLongOption = current.StartsWith(options.PrefixLongOption);
                 bool isShortOption = current.StartsWith(options.PrefixShortOption);
+                bool stopProcessing = !string.IsNullOrEmpty(options.StopParsingAfter) && current.Equals(options.StopParsingAfter);
+
+                if (stopProcessing)
+                {
+                    return new StopProcessingRecord(current);
+                }
 
                 if (isLongOption || isShortOption)
                 {
@@ -425,6 +443,14 @@ public void Dispose()
             }
         }
 
+        private sealed class StopProcessingRecord : ArgumentRecord
+        {
+            public StopProcessingRecord(string data)
+                : base(data)
+            {
+            }
+        }
+
         private sealed class CommandOrOptionValueRecord : ArgumentRecord
         {
             public CommandOrOptionValueRecord(string data)