Updating PicoArgs to v1.6.0

PicoArgs.cs

@@ -3,18 +3,19 @@ namespace PicoArgs_dotnet;
 /*  PICOARGS_DOTNET - a tiny command line argument parser for .NET
     https://github.com/lookbusy1344/PicoArgs-dotnet
 
-    Version 1.5.1 - 09 Jul 2024
+    Version 1.6.0 - 17 Jul 2024
 
     Example usage:
 
 	var pico = new PicoArgs(args);
 
 	bool verbose = pico.Contains("-v", "--verbose");  // true if any of these switches are present
-	string? pattern = pico.GetParamOpt("-t", "--pattern") ?? "*.txt";  // optional parameter
-	string requiredpath = pico.GetParam("-p", "--path");  // mandatory parameter, throws if not present
+	string? patternOpt = pico.GetParamOpt("-t", "--pattern");  // optional parameter
+	string pattern = pico.GetParamOpt("-t", "--pattern") ?? "*.txt";  // optional parameter with default
+	string requirePath = pico.GetParam("-p", "--path");  // mandatory parameter, throws if not present
 	string[] files = pico.GetMultipleParams("-f", "--file");  // multiple parameters returned in string[]
 	string command = pico.GetCommand();  // first parameter, throws if not present
-	string? commandopt = pico.GetCommandOpt();  // first parameter, null if not present
+	string? commandOpt = pico.GetCommandOpt();  // first parameter, null if not present
 
 	pico.Finished();  // We are done. Throw if there are any unused parameters
 
@@ -39,21 +40,15 @@ public class PicoArgs(IEnumerable<string> args, bool recogniseEquals = true)
 	/// </summary>
 	public bool Contains(params string[] options)
 	{
+		ValidateParams(options);
 		CheckFinished();
-		if (options == null || options.Length == 0) {
-			throw new ArgumentException("Must specify at least one option", nameof(options));
-		}
 
 		// no args left
 		if (args.Count == 0) {
 			return false;
 		}
 
 		foreach (var o in options) {
-			if (!o.StartsWith('-')) {
-				throw new ArgumentException("Must start with -", nameof(options));
-			}
-
 			var index = args.FindIndex(a => a.Key == o);
 			if (index >= 0) {
 				// if this argument has a value, throw eg "--verbose=true" when we just expected "--verbose"
@@ -77,10 +72,12 @@ public bool Contains(params string[] options)
 	/// </summary>
 	public string[] GetMultipleParams(params string[] options)
 	{
+		ValidateParams(options);
 		CheckFinished();
+
 		var result = new List<string>();
 		while (true) {
-			var s = GetParamOpt(options);
+			var s = GetParamInternal(options);  // Internal call, because we have already validated the options
 			if (s == null) {
 				break;   // nothing else found, break out of loop
 			}
@@ -93,32 +90,31 @@ public string[] GetMultipleParams(params string[] options)
 
 	/// <summary>
 	/// Get a string value from the command line, throws is not present
-	/// eg -a "value" or --foldera "value"
+	/// eg -a "value" or --folder "value"
 	/// </summary>
 	public string GetParam(params string[] options) => GetParamOpt(options) ?? throw new PicoArgsException(10, $"Expected value for \"{string.Join(", ", options)}\"");
 
 	/// <summary>
 	/// Get a string value from the command line, or null if not present
-	/// eg -a "value" or --foldera "value"
+	/// eg -a "value" or --folder "value"
 	/// </summary>
 	public string? GetParamOpt(params string[] options)
 	{
+		ValidateParams(options);
 		CheckFinished();
-		if (options == null || options.Length == 0) {
-			throw new ArgumentException("Must specify at least one option", nameof(options));
-		}
 
+		return GetParamInternal(options);
+	}
+
+	/// <summary>
+	/// Internal version of GetParamOpt, which does not check for valid options
+	/// </summary>
+	private string? GetParamInternal(string[] options)
+	{
 		if (args.Count == 0) {
 			return null;
 		}
 
-		// check all options are switches
-		foreach (var o in options) {
-			if (!o.StartsWith('-')) {
-				throw new ArgumentException("Must start with -", nameof(options));
-			}
-		}
-
 		// do we have this switch on command line?
 		var index = args.FindIndex(a => options.Contains(a.Key));
 		if (index == -1) {
@@ -140,16 +136,16 @@ public string[] GetMultipleParams(params string[] options)
 		}
 
 		// grab and check the next parameter
-		var seconditem = args[index + 1];
-		if (seconditem.Value != null) {
-			throw new PicoArgsException(30, $"Cannot identify value for param \"{item.Key}\", followed by \"{seconditem.Key}\" and \"{seconditem.Value}\"");
+		var secondItem = args[index + 1];
+		if (secondItem.Value != null) {
+			throw new PicoArgsException(30, $"Cannot identify value for param \"{item.Key}\", followed by \"{secondItem.Key}\" and \"{secondItem.Value}\"");
 		}
 
 		// consume the switch and the separate value
 		args.RemoveRange(index, 2);
 
 		// return the value
-		return seconditem.Key;
+		return secondItem.Key;
 	}
 
 	/// <summary>
@@ -210,6 +206,34 @@ private void CheckFinished()
 		}
 	}
 
+	/// <summary>
+	/// Check options are valid, eg -a or --action, but not -aa (already expanded) or ---action or --a
+	/// </summary>
+	private static void ValidateParams(string[] options)
+	{
+		if (options == null || options.Length == 0) {
+			throw new ArgumentException("Must specify at least one option", nameof(options));
+		}
+
+		foreach (var o in options) {
+			if (o.Length == 1 || !o.StartsWith('-')) {
+				throw new ArgumentException($"Options must start with a dash and be longer than 1 character: {o}", nameof(options));
+			}
+			if (o.Length > 2) {
+				if (o[1] != '-') {
+					// if it is longer than 2 characters, the second character must be a dash. eg -ab is invalid here (its already been expanded to -a -b)
+					throw new ArgumentException($"Long options must start with 2 dashes: {o}", nameof(options));
+				} else if (o[2] == '-') {
+					// if it is longer than 2 characters, the third character must not be a dash. eg ---a is not valid
+					throw new ArgumentException($"Options should not start with 3 dashes: {o}", nameof(options));
+				}
+				if (o.Length == 3) {
+					throw new ArgumentException($"Long options must be 2 characters or more: {o}", nameof(options));
+				}
+			}
+		}
+	}
+
 	/// <summary>
 	/// Helper function to process the command line arguments. Splits multiple switches into individual switches
 	/// eg -abc becomes -a -b -c