private static TemplateToken ReadValue(TextBuffer buffer, bool required)
{
var start = required ? '<' : '[';
var end = required ? '>' : ']';
var position = buffer.Position;
var kind = required ? TemplateToken.Kind.RequiredValue : TemplateToken.Kind.OptionalValue;
// Consume start of value character (< or [).
buffer.Consume(start);
var builder = new StringBuilder();
while (!buffer.ReachedEnd)
{
var character = buffer.Peek();
if (character == end)
{
break;
}
buffer.Read();
builder.Append(character);
}
if (buffer.ReachedEnd)
{
var name = builder.ToString();
var token = new TemplateToken(kind, position, name, $"{start}{name}");
throw CommandTemplateException.UnterminatedValueName(buffer.Original, token);
}
// Consume end of value character (> or ]).
buffer.Consume(end);
// Get the value (the text within the brackets).
var value = builder.ToString();
// Create a token and return it.
return(new TemplateToken(kind, position, value, required ? $"<{value}>" : $"[{value}]"));
}
public static IReadOnlyList <TemplateToken> Tokenize(string template)
{
using var buffer = new TextBuffer(template);
var result = new List <TemplateToken>();
while (!buffer.ReachedEnd)
{
EatWhitespace(buffer);
if (!buffer.TryPeek(out var character))
{
break;
}
if (character == '-')
{
result.Add(ReadOption(buffer));
}
else if (character == '|')
{
buffer.Consume('|');
}
else if (character == '<')
{
result.Add(ReadValue(buffer, true));
}
else if (character == '[')
{
result.Add(ReadValue(buffer, false));
}
else
{
throw CommandTemplateException.UnexpectedCharacter(buffer.Original, buffer.Position, character);
}
}
return(result);
}
public static ArgumentResult ParseArgumentTemplate(string template)
{
var valueName = default(string);
var required = false;
foreach (var token in TemplateTokenizer.Tokenize(template))
{
if (token.TokenKind == TemplateToken.Kind.ShortName ||
token.TokenKind == TemplateToken.Kind.LongName)
{
throw CommandTemplateException.ArgumentCannotContainOptions(template, token);
}
if (token.TokenKind == TemplateToken.Kind.OptionalValue ||
token.TokenKind == TemplateToken.Kind.RequiredValue)
{
if (!string.IsNullOrWhiteSpace(valueName))
{
throw CommandTemplateException.MultipleValuesAreNotSupported(template, token);
}
if (string.IsNullOrWhiteSpace(token.Value))
{
throw CommandTemplateException.ValuesMustHaveName(template, token);
}
valueName = token.Value;
required = token.TokenKind == TemplateToken.Kind.RequiredValue;
}
}
if (valueName == null)
{
throw CommandTemplateException.ArgumentsMustHaveValueName(template);
}
return(new ArgumentResult(valueName, required));
}
public static OptionResult ParseOptionTemplate(string template)
{
var result = new OptionResult();
foreach (var token in TemplateTokenizer.Tokenize(template))
{
if (token.TokenKind == TemplateToken.Kind.LongName || token.TokenKind == TemplateToken.Kind.ShortName)
{
if (string.IsNullOrWhiteSpace(token.Value))
{
throw CommandTemplateException.OptionsMustHaveName(template, token);
}
if (char.IsDigit(token.Value[0]))
{
throw CommandTemplateException.OptionNamesCannotStartWithDigit(template, token);
}
foreach (var character in token.Value)
{
if (!char.IsLetterOrDigit(character) && character != '-' && character != '_')
{
throw CommandTemplateException.InvalidCharacterInOptionName(template, token, character);
}
}
}
if (token.TokenKind == TemplateToken.Kind.LongName)
{
if (token.Value.Length == 1)
{
throw CommandTemplateException.LongOptionMustHaveMoreThanOneCharacter(template, token);
}
result.LongNames.Add(token.Value);
}
if (token.TokenKind == TemplateToken.Kind.ShortName)
{
if (token.Value.Length > 1)
{
throw CommandTemplateException.ShortOptionMustOnlyBeOneCharacter(template, token);
}
result.ShortNames.Add(token.Value);
}
if (token.TokenKind == TemplateToken.Kind.RequiredValue ||
token.TokenKind == TemplateToken.Kind.OptionalValue)
{
if (!string.IsNullOrWhiteSpace(result.Value))
{
throw CommandTemplateException.MultipleOptionValuesAreNotSupported(template, token);
}
foreach (var character in token.Value)
{
if (!char.IsLetterOrDigit(character) &&
character != '=' && character != '-' && character != '_')
{
throw CommandTemplateException.InvalidCharacterInValueName(template, token, character);
}
}
result.Value = token.Value.ToUpperInvariant();
result.ValueIsOptional = token.TokenKind == TemplateToken.Kind.OptionalValue;
}
}
if (result.LongNames.Count == 0 &&
result.ShortNames.Count == 0)
{
throw CommandTemplateException.MissingLongAndShortName(template, null);
}
return(result);
}
