public static StringSegment ParseJsCallExpression(this StringSegment literal, out JsCallExpression expression, bool filterExpression = false)
{
literal = literal.ParseIdentifier(out var token);
if (!(token is JsIdentifier identifier))
{
throw new SyntaxErrorException($"Expected identifier but instead found '{token}'");
}
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty() || literal.GetChar(0) != '(')
{
var isWhitespaceSyntax = filterExpression && literal.GetChar(0) == ':';
if (isWhitespaceSyntax)
{
literal = literal.Advance(1);
// replace everything after ':' up till new line and rewrite as single string to method
var endStringPos = literal.IndexOf("\n");
var endStatementPos = literal.IndexOf("}}");
if (endStringPos == -1 || (endStatementPos != -1 && endStatementPos < endStringPos))
{
endStringPos = endStatementPos;
}
if (endStringPos == -1)
{
throw new SyntaxErrorException($"Whitespace sensitive syntax did not find a '\\n' new line to mark the end of the statement, near '{literal.SubstringWithElipsis(0,50)}'");
}
var originalArg = literal.Subsegment(0, endStringPos).Trim().ToString();
var rewrittenArgs = originalArg.Replace("{", "{{").Replace("}", "}}");
var strArg = new JsLiteral(rewrittenArgs);
expression = new JsCallExpression(identifier, strArg);
return(literal.Subsegment(endStringPos));
}
expression = new JsCallExpression(identifier);
return(literal);
}
literal.Advance(1);
literal = literal.ParseArguments(out var args, termination: ')');
expression = new JsCallExpression(identifier, args.ToArray());
return(literal);
}
internal static StringSegment ParseArguments(this StringSegment literal, out List <JsToken> arguments, char termination)
{
arguments = new List <JsToken>();
literal = literal.Advance(1);
while (!literal.IsNullOrEmpty())
{
literal = literal.AdvancePastWhitespace();
if (literal.GetChar(0) == termination)
{
literal = literal.Advance(1);
break;
}
literal = literal.ParseJsExpression(out var listValue);
arguments.Add(listValue);
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty())
{
break;
}
if (literal.GetChar(0) == termination)
{
literal = literal.Advance(1);
break;
}
literal = literal.AdvancePastWhitespace();
var c = literal.GetChar(0);
if (c == termination)
{
literal = literal.Advance(1);
break;
}
if (c != ',')
{
throw new ArgumentException($"Unterminated arguments expression near: {literal.SubstringWithElipsis(0, 50)}");
}
literal = literal.Advance(1);
literal = literal.AdvancePastWhitespace();
}
literal = literal.AdvancePastWhitespace();
return(literal);
}
private static StringSegment ParseJsConditionalExpression(this StringSegment literal, JsToken test, out JsConditionalExpression expression)
{
literal = literal.Advance(1);
literal = literal.ParseJsExpression(out var consequent);
literal = literal.AdvancePastWhitespace();
if (!literal.FirstCharEquals(':'))
{
throw new SyntaxErrorException($"Expected Conditional ':' but was {literal.DebugFirstChar()}");
}
literal = literal.Advance(1);
literal = literal.ParseJsExpression(out var alternate);
expression = new JsConditionalExpression(test, consequent, alternate);
return(literal);
}
public static StringSegment ParseJsCallExpression(this StringSegment literal, out JsCallExpression expression, bool filterExpression = false)
{
literal = literal.ParseIdentifier(out var token);
if (!(token is JsIdentifier identifier))
{
throw new SyntaxErrorException($"Expected identifier but instead found {token.DebugToken()}");
}
literal = literal.AdvancePastWhitespace();
if (literal.FirstCharEquals(WhitespaceArgument))
{
literal = literal.Advance(1);
literal = literal.ParseWhitespaceArgument(out var argument);
expression = new JsCallExpression(identifier, argument);
return(literal);
}
if (literal.StartsWith("=>"))
{
literal = literal.ParseArrowExpressionBody(new[] { new JsIdentifier("it") }, out var arrowExpr);
expression = new JsCallExpression(identifier, arrowExpr);
return(literal);
}
if (!literal.FirstCharEquals('('))
{
expression = new JsCallExpression(identifier);
return(literal);
}
literal = literal.Advance(1);
literal = literal.ParseArguments(out var args, termination: ')');
expression = new JsCallExpression(identifier, args.ToArray());
return(literal);
}
public static StringSegment ParseNextToken(this StringSegment literal, out object value, out JsBinding binding, bool allowWhitespaceSyntax)
{
binding = null;
value = null;
var c = (char)0;
if (literal.IsNullOrEmpty())
{
return(TypeConstants.EmptyStringSegment);
}
var i = 0;
literal = literal.AdvancePastWhitespace();
var firstChar = literal.GetChar(0);
if (firstChar == '\'' || firstChar == '"' || firstChar == '`')
{
i = 1;
var hasEscapeChar = false;
while (i < literal.Length && ((c = literal.GetChar(i)) != firstChar || literal.GetChar(i - 1) == '\\'))
{
i++;
if (!hasEscapeChar)
{
hasEscapeChar = c == '\\';
}
}
if (i >= literal.Length || literal.GetChar(i) != firstChar)
{
throw new ArgumentException($"Unterminated string literal: {literal}");
}
var str = literal.Substring(1, i - 1);
value = str;
if (hasEscapeChar)
{
var sb = StringBuilderCache.Allocate();
for (var j = 0; j < str.Length; j++)
{
// strip the back-slash used to escape quote char in strings
var ch = str[j];
if (ch != '\\' || (j + 1 >= str.Length || str[j + 1] != firstChar))
{
sb.Append(ch);
}
}
value = StringBuilderCache.ReturnAndFree(sb);
}
return(literal.Advance(i + 1));
}
if (firstChar >= '0' && firstChar <= '9' || (literal.Length >= 2 && (firstChar == '-' || firstChar == '+') && literal.GetChar(1).IsNumericChar()))
{
i = 1;
var hasExponent = false;
var hasDecimal = false;
while (i < literal.Length && IsNumericChar(c = literal.GetChar(i)) ||
(hasExponent = (c == 'e' || c == 'E')))
{
if (c == '.')
{
hasDecimal = true;
}
i++;
if (hasExponent)
{
i += 2; // [e+1]0
while (i < literal.Length && IsNumericChar(literal.GetChar(i)))
{
i++;
}
break;
}
}
var numLiteral = literal.Subsegment(0, i);
//don't convert into ternary to avoid Type coercion
if (hasDecimal || hasExponent)
{
value = numLiteral.TryParseDouble(out double d) ? d : default(double);
}
else
{
value = numLiteral.ParseSignedInteger();
}
return(literal.Advance(i));
}
if (firstChar == '{')
{
var map = new Dictionary <string, object>();
literal = literal.Advance(1);
while (!literal.IsNullOrEmpty())
{
literal = literal.AdvancePastWhitespace();
if (literal.GetChar(0) == '}')
{
literal = literal.Advance(1);
break;
}
literal = literal.ParseNextToken(out object mapKeyString, out JsBinding mapKeyVar);
if (mapKeyVar is JsExpression)
{
throw new NotSupportedException($"JsExpression '{mapKeyVar?.Binding}' is not a valid Object key.");
}
var mapKey = mapKeyVar != null
? mapKeyVar.Binding.Value
: (string)mapKeyString;
if (mapKey != null)
{
literal = literal.AdvancePastWhitespace();
if (literal.Length > 0 && literal.GetChar(0) == ':')
{
literal = literal.Advance(1);
literal = literal.ParseNextToken(out object mapValue, out JsBinding mapValueBinding);
map[mapKey] = mapValue ?? mapValueBinding;
}
else //shorthand notation
{
if (literal.Length == 0 || (c = literal.GetChar(0)) != ',' && c != '}')
{
throw new ArgumentException($"Unterminated object literal near: {literal.SubstringWithElipsis(0, 50)}");
}
map[mapKey] = new JsBinding(mapKey);
}
}
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty())
{
break;
}
if (literal.GetChar(0) == '}')
{
literal = literal.Advance(1);
break;
}
literal = literal.AdvancePastChar(',');
literal = literal.AdvancePastWhitespace();
}
value = map;
return(literal);
}
if (firstChar == '[')
{
var list = new List <object>();
literal = literal.Advance(1);
while (!literal.IsNullOrEmpty())
{
literal = literal.AdvancePastWhitespace();
if (literal.GetChar(0) == ']')
{
literal = literal.Advance(1);
break;
}
literal = literal.ParseNextToken(out object mapValue, out JsBinding mapVarRef);
list.Add(mapVarRef ?? mapValue);
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty())
{
break;
}
if (literal.GetChar(0) == ']')
{
literal = literal.Advance(1);
break;
}
literal = literal.AdvancePastWhitespace();
c = literal.GetChar(0);
if (c == ']')
{
literal = literal.Advance(1);
break;
}
if (c != ',')
{
throw new ArgumentException($"Unterminated array literal near: {literal.SubstringWithElipsis(0, 50)}");
}
literal = literal.Advance(1);
literal = literal.AdvancePastWhitespace();
}
literal = literal.AdvancePastWhitespace();
value = list;
return(literal);
}
if (literal.StartsWith("true") && (literal.Length == 4 || !IsValidVarNameChar(literal.GetChar(4))))
{
value = true;
return(literal.Advance(4));
}
if (literal.StartsWith("false") && (literal.Length == 5 || !IsValidVarNameChar(literal.GetChar(5))))
{
value = false;
return(literal.Advance(5));
}
if (literal.StartsWith("null") && (literal.Length == 4 || !IsValidVarNameChar(literal.GetChar(4))))
{
value = JsNull.Value;
return(literal.Advance(4));
}
if (firstChar.IsOperatorChar())
{
if (literal.StartsWith(">="))
{
binding = JsGreaterThanEqual.Operand;
return(literal.Advance(2));
}
if (literal.StartsWith("<="))
{
binding = JsLessThanEqual.Operand;
return(literal.Advance(2));
}
if (literal.StartsWith("!=="))
{
binding = JsStrictNotEquals.Operand;
return(literal.Advance(3));
}
if (literal.StartsWith("!="))
{
binding = JsNotEquals.Operand;
return(literal.Advance(2));
}
if (literal.StartsWith("==="))
{
binding = JsStrictEquals.Operand;
return(literal.Advance(3));
}
if (literal.StartsWith("=="))
{
binding = JsEquals.Operand;
return(literal.Advance(2));
}
if (literal.StartsWith("||"))
{
binding = JsOr.Operator;
return(literal.Advance(2));
}
if (literal.StartsWith("&&"))
{
binding = JsAnd.Operator;
return(literal.Advance(2));
}
switch (firstChar)
{
case '>':
binding = JsGreaterThan.Operand;
return(literal.Advance(1));
case '<':
binding = JsLessThan.Operand;
return(literal.Advance(1));
case '=':
binding = JsAssignment.Operator;
return(literal.Advance(1));
case '!':
binding = JsNot.Operator;
return(literal.Advance(1));
case '+':
binding = JsAddition.Operator;
return(literal.Advance(1));
case '-':
binding = JsSubtraction.Operator;
return(literal.Advance(1));
case '*':
binding = JsMultiplication.Operator;
return(literal.Advance(1));
case '\\':
binding = JsDivision.Operator;
return(literal.Advance(1));
case '|':
binding = JsBitwiseOr.Operator;
return(literal.Advance(1));
case '&':
binding = JsBitwiseAnd.Operator;
return(literal.Advance(1));
default:
throw new NotSupportedException($"Invalid Operator found near: '{literal.SubstringWithElipsis(0, 50)}'");
}
}
// name
i = 1;
var isExpression = false;
var hadWhitespace = false;
while (i < literal.Length && IsValidVarNameChar(c = literal.GetChar(i)) ||
(isExpression = c.IsBindingExpressionChar() || (allowWhitespaceSyntax && c == ':')))
{
if (isExpression)
{
literal = literal.ParseNextExpression(out JsExpression expr);
binding = expr;
return(literal);
}
i++;
while (i < literal.Length && literal.GetChar(i).IsWhiteSpace()) // advance past whitespace
{
i++;
hadWhitespace = true;
}
if (hadWhitespace && (i >= literal.Length || !literal.GetChar(i).IsBindingExpressionChar()))
{
break;
}
}
binding = new JsBinding(literal.Subsegment(0, i).TrimEnd());
return(literal.Advance(i));
}
public static StringSegment ParseNextExpression(this StringSegment literal, out JsExpression binding)
{
var inDoubleQuotes = false;
var inSingleQuotes = false;
var inBackTickQuotes = false;
var inBrackets = 0;
var inBraces = 0;
var lastPos = 0;
for (var i = 0; i < literal.Length; i++)
{
var c = literal.GetChar(i);
if (c.IsWhiteSpace())
{
continue;
}
if (inDoubleQuotes)
{
if (c == '"')
{
inDoubleQuotes = false;
}
continue;
}
if (inSingleQuotes)
{
if (c == '\'')
{
inSingleQuotes = false;
}
continue;
}
if (inBackTickQuotes)
{
if (c == '`')
{
inBackTickQuotes = false;
}
continue;
}
if (inBrackets > 0)
{
if (c == '[')
{
++inBrackets;
}
if (c == ']')
{
--inBrackets;
}
continue;
}
if (inBraces > 0)
{
if (c == '{')
{
++inBraces;
}
if (c == '}')
{
--inBraces;
}
continue;
}
if (c == ':') //whitespace sensitive syntax
{
// replace everything after ':' up till new line and rewrite as single string to method
var endStringPos = literal.IndexOf("\n", i);
var endStatementPos = literal.IndexOf("}}", i);
if (endStringPos == -1 || (endStatementPos != -1 && endStatementPos < endStringPos))
{
endStringPos = endStatementPos;
}
if (endStringPos == -1)
{
throw new NotSupportedException($"Whitespace sensitive syntax did not find a '\\n' new line to mark the end of the statement, near '{literal.SubstringWithElipsis(i,50)}'");
}
binding = new JsExpression(literal.Subsegment(0, i).Trim());
var originalArgs = literal.Substring(i + 1, endStringPos - i - 1);
var rewrittenArgs = "`" + originalArgs.Trim().Replace("{", "{{").Replace("}", "}}").Replace("`", "\\`") + "`)";
ParseArguments(rewrittenArgs.ToStringSegment(), out List <StringSegment> args);
binding.Args = args;
return(literal.Subsegment(endStringPos));
}
if (c == '(')
{
var pos = i + 1;
binding = new JsExpression(literal.Subsegment(0, i).Trim());
literal = ParseArguments(literal.Subsegment(pos), out List <StringSegment> args);
binding.Args = args;
return(literal.Advance(1));
}
switch (c)
{
case '"':
inDoubleQuotes = true;
continue;
case '\'':
inSingleQuotes = true;
continue;
case '`':
inBackTickQuotes = true;
continue;
case '[':
inBrackets++;
continue;
case '{':
inBraces++;
continue;
}
if (!(c.IsValidVarNameChar() || c.IsBindingExpressionChar()))
{
binding = new JsExpression(literal.Subsegment(lastPos, i - lastPos).Trim());
return(literal.Advance(i));
}
}
binding = new JsExpression(literal.Subsegment(0, literal.Length));
return(TypeConstants.EmptyStringSegment);
}
// ( {args} , {args} )
// ^
public static StringSegment ParseArguments(StringSegment argsString, out List <StringSegment> args)
{
var to = new List <StringSegment>();
var inDoubleQuotes = false;
var inSingleQuotes = false;
var inBackTickQuotes = false;
var inBrackets = 0;
var inParens = 0;
var inBraces = 0;
var lastPos = 0;
for (var i = 0; i < argsString.Length; i++)
{
var c = argsString.GetChar(i);
if (inDoubleQuotes)
{
if (c == '"')
{
inDoubleQuotes = false;
}
continue;
}
if (inSingleQuotes)
{
if (c == '\'')
{
inSingleQuotes = false;
}
continue;
}
if (inBackTickQuotes)
{
if (c == '`')
{
inBackTickQuotes = false;
}
continue;
}
if (inBrackets > 0)
{
if (c == '[')
{
++inBrackets;
}
if (c == ']')
{
--inBrackets;
}
continue;
}
if (inBraces > 0)
{
if (c == '{')
{
++inBraces;
}
if (c == '}')
{
--inBraces;
}
continue;
}
if (inParens > 0)
{
if (c == '(')
{
++inParens;
}
if (c == ')')
{
--inParens;
}
continue;
}
switch (c)
{
case '"':
inDoubleQuotes = true;
continue;
case '\'':
inSingleQuotes = true;
continue;
case '`':
inBackTickQuotes = true;
continue;
case '[':
inBrackets++;
continue;
case '{':
inBraces++;
continue;
case '(':
inParens++;
continue;
case ',':
{
var arg = argsString.Subsegment(lastPos, i - lastPos).Trim();
to.Add(arg);
lastPos = i + 1;
continue;
}
case ')':
{
var arg = argsString.Subsegment(lastPos, i - lastPos).Trim();
if (!arg.IsNullOrEmpty())
{
to.Add(arg);
}
args = to;
return(argsString.Advance(i));
}
}
}
args = to;
return(TypeConstants.EmptyStringSegment);
}
public static StringSegment ParseNextExpression(this StringSegment literal, out JsExpression binding)
{
var inDoubleQuotes = false;
var inSingleQuotes = false;
var inBackTickQuotes = false;
var inBrackets = 0;
var inBraces = 0;
var lastPos = 0;
for (var i = 0; i < literal.Length; i++)
{
var c = literal.GetChar(i);
if (c.IsWhiteSpace())
{
continue;
}
if (inDoubleQuotes)
{
if (c == '"')
{
inDoubleQuotes = false;
}
continue;
}
if (inSingleQuotes)
{
if (c == '\'')
{
inSingleQuotes = false;
}
continue;
}
if (inBackTickQuotes)
{
if (c == '`')
{
inBackTickQuotes = false;
}
continue;
}
if (inBrackets > 0)
{
if (c == '[')
{
++inBrackets;
}
if (c == ']')
{
--inBrackets;
}
continue;
}
if (inBraces > 0)
{
if (c == '{')
{
++inBraces;
}
if (c == '}')
{
--inBraces;
}
continue;
}
if (c == '(')
{
var pos = i + 1;
binding = new JsExpression(literal.Subsegment(0, i).Trim());
literal = ParseArguments(literal.Subsegment(pos), out List <StringSegment> args);
binding.Args = args;
return(literal.Advance(1));
}
switch (c)
{
case '"':
inDoubleQuotes = true;
continue;
case '\'':
inSingleQuotes = true;
continue;
case '`':
inBackTickQuotes = true;
continue;
case '[':
inBrackets++;
continue;
case '{':
inBraces++;
continue;
}
if (!(c.IsValidVarNameChar() || c.IsBindingExpressionChar()))
{
binding = new JsExpression(literal.Subsegment(lastPos, i - lastPos).Trim());
return(literal.Advance(i));
}
}
binding = new JsExpression(literal.Subsegment(0, literal.Length));
return(TypeConstants.EmptyStringSegment);
}
internal static StringSegment ParseIdentifier(this StringSegment literal, out JsToken token)
{
var i = 0;
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty())
{
throw new SyntaxErrorException("Expected identifier before end");
}
var c = literal.GetChar(i);
if (!c.IsValidVarNameChar())
{
throw new SyntaxErrorException($"Expected start of identifier but was '{c}'");
}
i++;
while (i < literal.Length)
{
c = literal.GetChar(i);
if (IsValidVarNameChar(c))
{
i++;
}
else
{
break;
}
}
var identifier = literal.Subsegment(0, i).TrimEnd();
literal = literal.Advance(i);
if (identifier.Equals("true"))
{
token = JsLiteral.True;
}
else if (identifier.Equals("false"))
{
token = JsLiteral.False;
}
else if (identifier.Equals("null"))
{
token = JsNull.Value;
}
else if (identifier.Equals("and"))
{
token = JsAnd.Operator;
}
else if (identifier.Equals("or"))
{
token = JsOr.Operator;
}
else
{
token = new JsIdentifier(identifier);
}
return(literal);
}
public static StringSegment ParseJsToken(this StringSegment literal, out JsToken token, bool filterExpression)
{
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty())
{
token = null;
return(literal);
}
var c = literal.GetChar(0);
if (c == '(')
{
literal = literal.Advance(1);
literal = literal.ParseJsExpression(out var bracketsExpr);
literal = literal.AdvancePastWhitespace();
c = literal.GetChar(0);
if (c == ')')
{
literal = literal.Advance(1);
token = bracketsExpr;
return(literal);
}
throw new SyntaxErrorException($"Expected ')' but instead found '{c}': {literal.SubstringWithElipsis(0, 50)}");
}
token = null;
c = (char)0;
if (literal.IsNullOrEmpty())
{
return(TypeConstants.EmptyStringSegment);
}
var i = 0;
literal = literal.AdvancePastWhitespace();
var firstChar = literal.GetChar(0);
if (firstChar == '\'' || firstChar == '"' || firstChar == '`' || firstChar == '′')
{
i = 1;
var hasEscapeChar = false;
while (i < literal.Length && ((c = literal.GetChar(i)) != firstChar || literal.GetChar(i - 1) == '\\'))
{
i++;
if (!hasEscapeChar)
{
hasEscapeChar = c == '\\';
}
}
if (i >= literal.Length || literal.GetChar(i) != firstChar)
{
throw new SyntaxErrorException($"Unterminated string literal: {literal}");
}
var str = literal.Substring(1, i - 1);
token = new JsLiteral(str);
if (hasEscapeChar)
{
var sb = StringBuilderCache.Allocate();
for (var j = 0; j < str.Length; j++)
{
// strip the back-slash used to escape quote char in strings
var ch = str[j];
if (ch != '\\' || (j + 1 >= str.Length || str[j + 1] != firstChar))
{
sb.Append(ch);
}
}
token = new JsLiteral(StringBuilderCache.ReturnAndFree(sb));
}
return(literal.Advance(i + 1));
}
if (firstChar >= '0' && firstChar <= '9')
{
i = 1;
var hasExponent = false;
var hasDecimal = false;
while (i < literal.Length && IsNumericChar(c = literal.GetChar(i)) ||
(hasExponent = (c == 'e' || c == 'E')))
{
if (c == '.')
{
hasDecimal = true;
}
i++;
if (hasExponent)
{
i += 2; // [e+1]0
while (i < literal.Length && IsNumericChar(literal.GetChar(i)))
{
i++;
}
break;
}
}
var numLiteral = literal.Subsegment(0, i);
//don't convert into ternary to avoid Type coercion
if (hasDecimal || hasExponent)
{
token = new JsLiteral(numLiteral.TryParseDouble(out double d) ? d : default(double));
}
else
{
token = new JsLiteral(numLiteral.ParseSignedInteger());
}
return(literal.Advance(i));
}
if (firstChar == '{')
{
var props = new List <JsProperty>();
literal = literal.Advance(1);
while (!literal.IsNullOrEmpty())
{
literal = literal.AdvancePastWhitespace();
if (literal.GetChar(0) == '}')
{
literal = literal.Advance(1);
break;
}
literal = literal.ParseJsToken(out var mapKeyToken);
if (!(mapKeyToken is JsLiteral) && !(mapKeyToken is JsIdentifier))
{
throw new SyntaxErrorException($"'{mapKeyToken}' is not a valid Object key, expected literal or identifier.");
}
JsToken mapValueToken;
bool shorthand = false;
literal = literal.AdvancePastWhitespace();
if (literal.Length > 0 && literal.GetChar(0) == ':')
{
literal = literal.Advance(1);
literal = literal.ParseJsExpression(out mapValueToken);
}
else
{
shorthand = true;
if (literal.Length == 0 || (c = literal.GetChar(0)) != ',' && c != '}')
{
throw new SyntaxErrorException($"Unterminated object literal near: {literal.SubstringWithElipsis(0, 50)}");
}
mapValueToken = mapKeyToken;
}
props.Add(new JsProperty(mapKeyToken, mapValueToken, shorthand));
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty())
{
break;
}
if (literal.GetChar(0) == '}')
{
literal = literal.Advance(1);
break;
}
literal = literal.AdvancePastChar(',');
literal = literal.AdvancePastWhitespace();
}
token = new JsObjectExpression(props);
return(literal);
}
if (firstChar == '[')
{
literal = literal.ParseArguments(out var elements, termination: ']');
token = new JsArrayExpression(elements);
return(literal);
}
if (firstChar.IsOperatorChar())
{
if (literal.StartsWith(">="))
{
token = JsGreaterThanEqual.Operator;
return(literal.Advance(2));
}
if (literal.StartsWith("<="))
{
token = JsLessThanEqual.Operator;
return(literal.Advance(2));
}
if (literal.StartsWith("!=="))
{
token = JsStrictNotEquals.Operator;
return(literal.Advance(3));
}
if (literal.StartsWith("!="))
{
token = JsNotEquals.Operator;
return(literal.Advance(2));
}
if (literal.StartsWith("==="))
{
token = JsStrictEquals.Operator;
return(literal.Advance(3));
}
if (literal.StartsWith("=="))
{
token = JsEquals.Operator;
return(literal.Advance(2));
}
if (literal.StartsWith("||"))
{
token = JsOr.Operator;
return(literal.Advance(2));
}
if (literal.StartsWith("&&"))
{
token = JsAnd.Operator;
return(literal.Advance(2));
}
if (literal.StartsWith("<<"))
{
token = JsBitwiseLeftShift.Operator;
return(literal.Advance(2));
}
if (literal.StartsWith(">>"))
{
token = JsBitwiseRightShift.Operator;
return(literal.Advance(2));
}
switch (firstChar)
{
case '>':
token = JsGreaterThan.Operator;
return(literal.Advance(1));
case '<':
token = JsLessThan.Operator;
return(literal.Advance(1));
case '=':
token = JsAssignment.Operator;
return(literal.Advance(1));
case '!':
token = JsNot.Operator;
return(literal.Advance(1));
case '+':
token = JsAddition.Operator;
return(literal.Advance(1));
case '-':
token = JsSubtraction.Operator;
return(literal.Advance(1));
case '*':
token = JsMultiplication.Operator;
return(literal.Advance(1));
case '/':
token = JsDivision.Operator;
return(literal.Advance(1));
case '&':
token = JsBitwiseAnd.Operator;
return(literal.Advance(1));
case '|':
token = JsBitwiseOr.Operator;
return(literal.Advance(1));
case '^':
token = JsBitwiseXOr.Operator;
return(literal.Advance(1));
case '%':
token = JsMod.Operator;
return(literal.Advance(1));
default:
throw new SyntaxErrorException($"Invalid Operator found near: '{literal.SubstringWithElipsis(0, 50)}'");
}
}
// identifier
var preIdentifierLiteral = literal;
literal = literal.ParseIdentifier(out var node);
literal = literal.AdvancePastWhitespace();
if (!literal.IsNullOrEmpty())
{
c = literal.GetChar(i);
if (c == '.' || c == '[')
{
while (true)
{
literal = literal.Advance(1);
if (c == '.')
{
literal = literal.AdvancePastWhitespace();
literal = literal.ParseIdentifier(out var property);
node = new JsMemberExpression(node, property, computed: false);
}
else if (c == '[')
{
literal = literal.AdvancePastWhitespace();
literal = literal.ParseJsExpression(out var property);
node = new JsMemberExpression(node, property, computed: true);
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty() || literal.GetChar(0) != ']')
{
throw new SyntaxErrorException($"Expected ']' but was '{literal.GetChar(0)}'");
}
literal = literal.Advance(1);
}
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrWhiteSpace())
{
break;
}
c = literal.GetChar(0);
if (c == '(')
{
throw new SyntaxErrorException("Call expression found on member expression. Only filters can be invoked.");
}
if (!(c == '.' || c == '['))
{
break;
}
}
}
else if (c == '(' || (filterExpression && c == ':'))
{
literal = preIdentifierLiteral.ParseJsCallExpression(out var callExpr, filterExpression: filterExpression);
token = callExpr;
return(literal);
}
}
token = node;
return(literal);
}
internal static StringSegment ParseArguments(this StringSegment literal, out List <JsToken> arguments, char termination)
{
arguments = new List <JsToken>();
while (!literal.IsNullOrEmpty())
{
JsToken listValue;
literal = literal.AdvancePastWhitespace();
if (literal.GetChar(0) == termination)
{
literal = literal.Advance(1);
break;
}
if (literal.StartsWith("..."))
{
literal = literal.Advance(3);
literal = literal.ParseJsExpression(out listValue);
if (!(listValue is JsIdentifier) && !(listValue is JsArrayExpression))
{
throw new SyntaxErrorException($"Spread operator expected array but instead found {listValue.DebugToken()}");
}
listValue = new JsSpreadElement(listValue);
}
else
{
literal = literal.ParseJsExpression(out listValue);
}
arguments.Add(listValue);
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty())
{
break;
}
if (literal.GetChar(0) == termination)
{
literal = literal.Advance(1);
break;
}
literal = literal.AdvancePastWhitespace();
var c = literal.SafeGetChar(0);
if (c.IsEnd() || c == termination)
{
literal = literal.Advance(1);
break;
}
if (c != ',')
{
throw new SyntaxErrorException($"Unterminated arguments expression near: {literal.DebugLiteral()}");
}
literal = literal.Advance(1);
literal = literal.AdvancePastWhitespace();
}
literal = literal.AdvancePastWhitespace();
return(literal);
}
public static StringSegment ParseNextToken(this StringSegment literal, out object value, out JsBinding binding)
{
binding = null;
value = null;
var c = (char)0;
if (literal.IsNullOrEmpty())
{
return(TypeConstants.EmptyStringSegment);
}
var i = 0;
literal = literal.AdvancePastWhitespace();
var firstChar = literal.GetChar(0);
if (firstChar == '\'' || firstChar == '"')
{
i = 1;
while (i < literal.Length && (literal.GetChar(i) != firstChar || literal.GetChar(i - 1) == '\\'))
{
i++;
}
if (i >= literal.Length || literal.GetChar(i) != firstChar)
{
throw new ArgumentException($"Unterminated string literal: {literal}");
}
value = literal.Substring(1, i - 1);
return(literal.Advance(i));
}
if (firstChar >= '0' && firstChar <= '9' || firstChar == '-' || firstChar == '+')
{
i = 1;
var hasExponent = false;
var hasDecimal = false;
while (i < literal.Length && IsValidNumericChar(c = literal.GetChar(i)) ||
(hasExponent = (c == 'e' || c == 'E')))
{
if (c == '.')
{
hasDecimal = true;
}
i++;
if (hasExponent)
{
i += 2; // [e+1]0
while (i < literal.Length && IsValidNumericChar(literal.GetChar(i)))
{
i++;
}
break;
}
}
var numLiteral = literal.Subsegment(0, i);
//don't convert into ternary to avoid Type coercion
if (hasDecimal || hasExponent)
{
value = numLiteral.TryParseDouble(out double d) ? d : default(double);
}
else
{
value = numLiteral.ParseSignedInteger();
}
return(literal.Advance(i));
}
if (firstChar == '{')
{
var map = new Dictionary <string, object>();
literal = literal.Advance(1);
while (!literal.IsNullOrEmpty())
{
literal = literal.ParseNextToken(out object mapKeyString, out JsBinding mapKeyVar);
if (mapKeyVar is JsExpression)
{
throw new NotSupportedException($"JsExpression '{mapKeyVar?.Binding}' is not a valid Object key.");
}
var mapKey = mapKeyVar != null
? mapKeyVar.Binding.Value
: (string)mapKeyString;
if (mapKey != null)
{
literal = literal.AdvancePastChar(':');
literal = literal.ParseNextToken(out object mapValue, out JsBinding mapValueBinding);
map[mapKey] = mapValue ?? mapValueBinding;
}
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty())
{
break;
}
if (literal.GetChar(0) == '}')
{
literal = literal.Advance(1);
break;
}
literal = literal.AdvancePastChar(',');
literal = literal.AdvancePastWhitespace();
}
value = map;
return(literal);
}
if (firstChar == '[')
{
var list = new List <object>();
literal = literal.Advance(1);
while (!literal.IsNullOrEmpty() && literal.GetChar(0) != ']')
{
literal = literal.ParseNextToken(out object mapValue, out JsBinding mapVarRef);
list.Add(mapVarRef ?? mapValue);
literal = literal.AdvancePastWhitespace();
if (literal.IsNullOrEmpty())
{
break;
}
if (literal.GetChar(0) == ']')
{
literal = literal.Advance(1);
break;
}
literal = literal.AdvancePastChar(',');
literal = literal.AdvancePastWhitespace();
}
value = list;
return(literal);
}
if (literal.StartsWith("true") && (literal.Length == 4 || !IsValidVarNameChar(literal.GetChar(4))))
{
value = true;
return(literal.Advance(4));
}
if (literal.StartsWith("false") && (literal.Length == 5 || !IsValidVarNameChar(literal.GetChar(5))))
{
value = false;
return(literal.Advance(5));
}
if (literal.StartsWith("null") && (literal.Length == 4 || !IsValidVarNameChar(literal.GetChar(4))))
{
value = JsNull.Value;
return(literal.Advance(4));
}
// name
i = 1;
var isExpression = false;
while (i < literal.Length && IsValidVarNameChar(c = literal.GetChar(i)) ||
(isExpression = (c == '.' || c == '(' || c == '[')))
{
if (isExpression)
{
binding = literal.ParseJsExpression(out int pos).FirstOrDefault();
return(literal.Advance(pos));
}
i++;
while (i < literal.Length && literal.GetChar(i).IsWhiteSpace()) // advance past whitespace
{
i++;
}
}
binding = new JsBinding(literal.Subsegment(0, i).TrimEnd());
return(literal.Advance(i));
}