private ScriptConditionStatement ParseElseStatement(bool isElseIf)
{
// Case of elsif
if (_isLiquid && isElseIf)
{
return(ParseIfStatement(false, ScriptKeyword.Else()));
}
// unit test: 200-if-else-statement.txt
var nextToken = PeekToken();
if (!_isLiquid && nextToken.Type == TokenType.Identifier && GetAsText(nextToken) == "if")
{
var elseKeyword = ScriptKeyword.Else();
ExpectAndParseKeywordTo(elseKeyword);
return(ParseIfStatement(false, elseKeyword));
}
var elseStatement = Open <ScriptElseStatement>();
ExpectAndParseKeywordTo(elseStatement.ElseKeyword); // Parse else statement
// unit test: 201-if-else-error4.txt
if (ExpectEndOfStatement())
{
elseStatement.Body = ParseBlockStatement(elseStatement);
}
return(Close(elseStatement));
}
private ScriptIfStatement ParseIfStatement(bool invert, ScriptKeyword elseKeyword = null)
{
// unit test: 200-if-else-statement.txt
var ifStatement = Open <ScriptIfStatement>();
ifStatement.ElseKeyword = elseKeyword;
if (_isLiquid && elseKeyword != null)
{
// Parse elseif
Open(ifStatement.IfKeyword);
NextToken();
Close(ifStatement.IfKeyword);
}
else
{
if (_isLiquid && invert) // we have an unless
{
Open(ifStatement.IfKeyword); // still transfer trivias to IfKeyword
NextToken();
Close(ifStatement.IfKeyword);
}
else
{
ExpectAndParseKeywordTo(ifStatement.IfKeyword); // Parse if keyword
}
}
var condition = ExpectAndParseExpression(ifStatement, allowAssignment: false);
// Transform a `if condition` to `if !(condition)`
if (invert)
{
var invertCondition = ScriptUnaryExpression.Wrap(ScriptUnaryOperator.Not, ScriptToken.Exclamation(), ScriptNestedExpression.Wrap(condition, _isKeepTrivia), _isKeepTrivia);
condition = invertCondition;
}
ifStatement.Condition = condition;
if (ExpectEndOfStatement())
{
ifStatement.Then = ParseBlockStatement(ifStatement);
}
return(Close(ifStatement));
}
public ScriptEndStatement()
{
EndKeyword = ScriptKeyword.End();
CanSkipEvaluation = true;
}
public ScriptBreakStatement()
{
BreakKeyword = ScriptKeyword.Break();
}
private ScriptFunction ParseFunctionStatement(bool isAnonymous)
{
var scriptFunction = Open <ScriptFunction>();
var previousExpressionLevel = _expressionLevel;
try
{
// Reset expression level when parsing
_expressionLevel = 0;
if (isAnonymous)
{
scriptFunction.NameOrDoToken = ExpectAndParseKeywordTo(ScriptKeyword.Do());
}
else
{
scriptFunction.FuncToken = ExpectAndParseKeywordTo(ScriptKeyword.Func());
scriptFunction.NameOrDoToken = ExpectAndParseVariable(scriptFunction);
}
// If we have parenthesis, this is a function with explicit parameters
if (Current.Type == TokenType.OpenParen)
{
scriptFunction.OpenParen = ParseToken(TokenType.OpenParen);
var parameters = new ScriptList <ScriptParameter>();
bool hasTripleDot = false;
bool hasOptionals = false;
bool isFirst = true;
while (true)
{
// Parse any required comma (before each new non-first argument)
// Or closing parent (and we exit the loop)
if (Current.Type == TokenType.CloseParen)
{
scriptFunction.CloseParen = ParseToken(TokenType.CloseParen);
scriptFunction.Span.End = scriptFunction.CloseParen.Span.End;
break;
}
if (!isFirst)
{
if (Current.Type == TokenType.Comma)
{
PushTokenToTrivia();
NextToken();
FlushTriviasToLastTerminal();
}
else
{
LogError(Current, "Expecting a comma to separate arguments in a function call.");
}
}
isFirst = false;
// Else we expect an expression
if (IsStartOfExpression())
{
var parameter = Open <ScriptParameter>();
var arg = ExpectAndParseVariable(scriptFunction);
if (!(arg is ScriptVariableGlobal))
{
LogError(arg.Span, "Expecting only a simple name parameter for a function");
}
parameter.Name = arg;
if (Current.Type == TokenType.Equal)
{
if (hasTripleDot)
{
LogError(arg.Span, "Cannot declare an optional parameter after a variable parameter (`...`).");
}
hasOptionals = true;
parameter.EqualOrTripleDotToken = ScriptToken.Equal();
ExpectAndParseTokenTo(parameter.EqualOrTripleDotToken, TokenType.Equal);
parameter.Span.End = parameter.EqualOrTripleDotToken.Span.End;
var defaultValue = ExpectAndParseExpression(parameter);
if (defaultValue is ScriptLiteral literal)
{
parameter.DefaultValue = literal;
parameter.Span.End = literal.Span.End;
}
else
{
LogError(arg.Span, "Expecting only a literal for an optional parameter value.");
}
}
else if (Current.Type == TokenType.TripleDot)
{
if (hasTripleDot)
{
LogError(arg.Span, "Cannot declare multiple variable parameters.");
}
hasTripleDot = true;
hasOptionals = true;
parameter.EqualOrTripleDotToken = ScriptToken.TripleDot();
ExpectAndParseTokenTo(parameter.EqualOrTripleDotToken, TokenType.TripleDot);
parameter.Span.End = parameter.EqualOrTripleDotToken.Span.End;
}
else if (hasOptionals)
{
LogError(arg.Span, "Cannot declare a normal parameter after an optional parameter.");
}
parameters.Add(parameter);
scriptFunction.Span.End = parameter.Span.End;
}
else
{
LogError(Current, "Expecting an expression for argument function calls instead of this token.");
break;
}
}
if (scriptFunction.CloseParen == null)
{
LogError(Current, "Expecting a closing parenthesis for a function call.");
}
// Setup parameters once they have been all parsed
scriptFunction.Parameters = parameters;
}
ExpectEndOfStatement();
// If the function is anonymous we don't expect an EOS after the `end`
scriptFunction.Body = ParseBlockStatement(scriptFunction, !isAnonymous);
}
finally
{
_expressionLevel = previousExpressionLevel;
}
return(Close(scriptFunction));
}
