refactor(cli): Extract argument validation and reorganize parsing logic

Author: arturcic

src/GitVersion.App/ArgumentParser.cs

@@ -49,25 +49,7 @@ public Arguments ParseArguments(string[] commandLineArguments)
         var (rootCommand, options) = commandFactory.Value;
         var parseResult = rootCommand.Parse(commandLineArguments);
 
-        if (parseResult.Errors.Count > 0)
-        {
-            var message = parseResult.Errors[0].Message;
-            var token = message.Contains("Unrecognized command or argument")
-                ? ExtractUnrecognizedToken(message)
-                : message;
-            throw new WarningException($"Could not parse command line parameter '{token}'.");
-        }
-
-        if (parseResult.UnmatchedTokens.Count > 0)
-        {
-            throw new WarningException($"Could not parse command line parameter '{parseResult.UnmatchedTokens[0]}'.");
-        }
-
-        var positionalCheck = parseResult.GetValue(options.Path);
-        if (positionalCheck?.StartsWith('-') == true)
-        {
-            throw new WarningException($"Could not parse command line parameter '{positionalCheck}'.");
-        }
+        ValidateParsedResult(parseResult, options);
 
         if (IsOptionExplicitlySet<HelpOption>())
         {
@@ -83,33 +65,37 @@ public Arguments ParseArguments(string[] commandLineArguments)
         var arguments = new Arguments();
         AddAuthentication(arguments);
         MapParsedValues(arguments, parseResult, options);
+        ValidateConfigurationFile(arguments);
 
-        if (arguments.Output.Count == 0)
+        return arguments;
+
+        bool IsOptionExplicitlySet<T>() where T : Option
         {
-            arguments.Output.Add(OutputType.Json);
+            var option = rootCommand.Options.SingleOfType<T>();
+            return parseResult.GetResult(option) is { Implicit: false };
         }
+    }
 
-        if (arguments.Output.Contains(OutputType.File) && arguments.OutputFile == null)
+    private static void ValidateParsedResult(ParseResult parseResult, CommandOptions options)
+    {
+        if (parseResult.Errors.Count > 0)
         {
-            arguments.OutputFile = DefaultOutputFileName;
+            var message = parseResult.Errors[0].Message;
+            var token = message.Contains("Unrecognized command or argument")
+                ? ExtractUnrecognizedToken(message)
+                : message;
+            throw new WarningException($"Could not parse command line parameter '{token}'.");
         }
 
-        arguments.TargetPath ??= parseResult.GetValue(options.Path) ?? SysEnv.CurrentDirectory;
-        arguments.TargetPath = arguments.TargetPath.TrimEnd('/', '\\');
-
-        if (!arguments.EnsureAssemblyInfo)
+        if (parseResult.UnmatchedTokens.Count > 0)
         {
-            arguments.UpdateAssemblyInfoFileName = ResolveFiles(arguments.TargetPath, arguments.UpdateAssemblyInfoFileName).ToHashSet();
+            throw new WarningException($"Could not parse command line parameter '{parseResult.UnmatchedTokens[0]}'.");
         }
 
-        ValidateConfigurationFile(arguments);
-
-        return arguments;
-
-        bool IsOptionExplicitlySet<T>() where T : Option
+        var positionalCheck = parseResult.GetValue(options.Path);
+        if (positionalCheck?.StartsWith('-') == true)
         {
-            var option = rootCommand.Options.SingleOfType<T>();
-            return parseResult.GetResult(option) is { Implicit: false };
+            throw new WarningException($"Could not parse command line parameter '{positionalCheck}'.");
         }
     }
 
@@ -270,6 +256,24 @@ private void MapParsedValues(Arguments arguments, ParseResult parseResult, Comma
         {
             arguments.ClonePath = dynRepo;
         }
+
+        if (arguments.Output.Count == 0)
+        {
+            arguments.Output.Add(OutputType.Json);
+        }
+
+        if (arguments.Output.Contains(OutputType.File) && arguments.OutputFile == null)
+        {
+            arguments.OutputFile = DefaultOutputFileName;
+        }
+
+        arguments.TargetPath ??= parseResult.GetValue(options.Path) ?? SysEnv.CurrentDirectory;
+        arguments.TargetPath = arguments.TargetPath.TrimEnd('/', '\\');
+
+        if (!arguments.EnsureAssemblyInfo)
+        {
+            arguments.UpdateAssemblyInfoFileName = ResolveFiles(arguments.TargetPath, arguments.UpdateAssemblyInfoFileName).ToHashSet();
+        }
     }
 
     private static bool IsBooleanTrue(string value) =>
@@ -442,7 +446,10 @@ Allows GitVersion to run on a shallow clone.
 
         // Configure the built-in help system to wrap at 260 characters to avoid too small help messages
         var helpOption = rootCommand.Options.SingleOfType<HelpOption>();
-        helpOption.Action = new HelpAction { MaxWidth = 260 };
+        if (helpOption.Action is HelpAction helpAction)
+        {
+            helpAction.MaxWidth = 260;
+        }
 
         return (rootCommand, new CommandOptions(
             Path: path, Diagnose: diagnose, LogFile: logFile,