(GH-473) Correct exit code when help is requested

There are two cases when choco shows help message: when it is
explicitly requested or when parsing fails. In first scenario
choco should return 0 exit code, in second - non-zero value.
This commit introduces new property UnsuccessfulParsing in
ChocolateyConfiguration and using this property it fixes bug
with incorrect exit code.

src/chocolatey.console/Program.cs

@@ -105,10 +105,10 @@ private static void Main(string[] args)
                     }
                 }
 
-                if (config.HelpRequested)
+                if (config.HelpRequested || config.UnsuccessfulParsing)
                 {
                     pause_execution_if_debug();
-                    Environment.Exit(-1);
+                    Environment.Exit(config.UnsuccessfulParsing? 1 : 0);
                 }
 
                 Log4NetAppenderConfiguration.set_logging_level_debug_when_debug(config.Debug, excludeLoggerName: "{0}LoggingColoredConsoleAppender".format_with(ChocolateyLoggers.Verbose.to_string()));

src/chocolatey.tests.integration/Scenario.cs

@@ -142,6 +142,7 @@ private static ChocolateyConfiguration baseline_configuration()
             config.ForceDependencies = false;
             config.ForceX86 = false;
             config.HelpRequested = false;
+            config.UnsuccessfulParsing = false;
             config.IgnoreDependencies = false;
             config.InstallArguments = string.Empty;
             config.Noop = false;

src/chocolatey.tests/infrastructure.app/configuration/ConfigurationOptionsSpec.cs

@@ -312,6 +312,26 @@ public void should_show_help_menu_when_passing_bundled_options_that_do_not_exist
                 config.Debug.ShouldBeFalse();
                 helpMessageContents.ToString().ShouldNotBeEmpty();
             }
+
+            [Fact]
+            public void should_successfully_parse_help_option()
+            {
+                args.Add("-h");
+
+                because();
+
+                config.UnsuccessfulParsing.ShouldBeFalse();
+            }
+
+            [Fact]
+            public void should_not_parse_unknown_option()
+            {
+                args.Add("-unknown");
+
+                because();
+
+                config.UnsuccessfulParsing.ShouldBeTrue();
+            }
         }
     }
 }

src/chocolatey/infrastructure.app/builders/ConfigurationBuilder.cs

@@ -391,6 +391,7 @@ private static void set_global_options(IList<string> args, ChocolateyConfigurati
                     {
                         // save help for next menu
                         config.HelpRequested = false;
+                        config.UnsuccessfulParsing = false;
                     }
                 },
                 () => { },

src/chocolatey/infrastructure.app/configuration/ChocolateyConfiguration.cs

@@ -157,6 +157,10 @@ private void append_output(StringBuilder propertyValues, string append)
         public bool Force { get; set; }
         public bool Noop { get; set; }
         public bool HelpRequested { get; set; }
+        /// <summary>
+        ///   Gets or sets a value indicating whether parsing was successful (everything parsed) or not.
+        /// </summary>
+        public bool UnsuccessfulParsing { get; set; }
 
         // TODO: Should look into using mutually exclusive output levels - Debug, Info (Regular), Error (Quiet)
         // Verbose and Important are not part of the levels at all

src/chocolatey/infrastructure.app/configuration/ConfigurationOptions.cs

@@ -85,6 +85,7 @@ private static IConsole Console
             catch (OptionException)
             {
                 show_help(_optionSet, helpMessage);
+                configuration.UnsuccessfulParsing = true;
             }
 
             // the command argument
@@ -102,6 +103,7 @@ private static IConsole Console
                 else
                 {
                     configuration.HelpRequested = true;
+                    configuration.UnsuccessfulParsing = true;
                 }
             }
 

src/chocolatey/infrastructure.app/runners/ConsoleApplication.cs

@@ -64,7 +64,7 @@ public void run(string[] args, ChocolateyConfiguration config, Container contain
 
                 commandArgs.Add(arg);
             }
-
+            
             var runner = new GenericRunner();
             runner.run(config, container, isConsole: true, parseArgs: command =>
                 {
@@ -89,6 +89,7 @@ public void run(string[] args, ChocolateyConfiguration config, Container contain
                                     if (unparsedArg.StartsWith("-") || unparsedArg.StartsWith("/"))
                                     {
                                         config.HelpRequested = true;
+                                        config.UnsuccessfulParsing = true;
                                     }
                                 }
                             }

src/chocolatey/infrastructure.app/runners/GenericRunner.cs

@@ -75,13 +75,13 @@ private ICommand find_command(ChocolateyConfiguration config, Container containe
                 this.Log().Debug(() => "Configuration: {0}".format_with(config.ToString()));
 
 
-                if (isConsole && config.HelpRequested)
+                if (isConsole && (config.HelpRequested || config.UnsuccessfulParsing))
                 {
 #if DEBUG
                     Console.WriteLine("Press enter to continue...");
                     Console.ReadKey();
 #endif
-                    Environment.Exit(1);
+                    Environment.Exit(config.UnsuccessfulParsing? 1 : 0);
                 }
 
                 var token = Assembly.GetExecutingAssembly().get_public_key_token();