private HoconValue ResolveSubstitution(HoconSubstitution sub)
{
var subField = sub.ParentField;
// first case, this substitution is a direct self-reference
if (sub.Path == subField.Path)
{
var parent = sub.Parent;
while (parent is HoconValue)
{
parent = parent.Parent;
}
// Fail case
if (parent is HoconArray)
{
throw new HoconException("Self-referencing substitution may not be declared within an array.");
}
// try to resolve substitution by looking backward in the field assignment stack
return(subField.OlderValueThan(sub));
}
// second case, the substitution references a field child in the past
if (sub.Path.IsChildPathOf(subField.Path))
{
var olderValue = subField.OlderValueThan(sub);
if (olderValue.Type == HoconType.Object)
{
var difLength = sub.Path.Count - subField.Path.Count;
var deltaPath = sub.Path.SubPath(sub.Path.Count - difLength, difLength);
var olderObject = olderValue.GetObject();
if (olderObject.TryGetValue(deltaPath, out var innerValue))
{
return(innerValue.Type == HoconType.Object ? innerValue : null);
}
}
}
// Detect invalid parent-referencing substitution
if (subField.Path.IsChildPathOf(sub.Path))
{
throw new HoconException("Substitution may not reference one of its direct parents.");
}
// Detect invalid cyclic reference loop
if (IsValueCyclic(subField, sub))
{
throw new HoconException("A cyclic substitution loop is detected in the Hocon file.");
}
// third case, regular substitution
_root.GetObject().TryGetValue(sub.Path, out var field);
return(field?.Clone(field.Parent) as HoconValue);
}
// The owner in this context can be either an object or an array.
private void ParseObject(ref HoconValue owner)
{
if (owner == null)
{
throw HoconParserException.Create(_tokens.Current, Path,
"ParseObject called with null parent.");
}
// Sanity check
if (_tokens.Current.Type != TokenType.StartOfObject)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon object. Expected `{TokenType.StartOfObject}`, found `{_tokens.Current.Type}` instead.");
}
// Consume curly bracket
_tokens.ToNextSignificant();
var hoconObject = owner.GetObject();
if (hoconObject == null)
{
hoconObject = new HoconObject(owner);
owner.Add(hoconObject);
}
var valueWasParsed = false;
var parsing = true;
while (parsing)
{
switch (_tokens.Current.Type)
{
case TokenType.Include:
if (valueWasParsed)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon object. Expected `{TokenType.Comma}` or `{TokenType.EndOfLine}`, " +
$"found `{_tokens.Current.Type}` instead.");
}
owner.ReParent(ParseInclude());
valueWasParsed = true;
break;
case TokenType.LiteralValue:
if (_tokens.Current.IsNonSignificant())
{
_tokens.ToNextSignificant();
}
if (_tokens.Current.Type != TokenType.LiteralValue)
{
break;
}
if (valueWasParsed)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon object. Expected `{TokenType.Comma}` or `{TokenType.EndOfLine}`, " +
$"found `{_tokens.Current.Type}` instead.");
}
ParseField(hoconObject);
valueWasParsed = true;
break;
case TokenType.Comment:
case TokenType.EndOfLine:
valueWasParsed = false;
_tokens.ToNextSignificantLine();
break;
case TokenType.Comma:
if (!valueWasParsed)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon object. Expected `{TokenType.Assign}` or `{TokenType.StartOfObject}`, " +
$"found `{_tokens.Current.Type}` instead.");
}
valueWasParsed = false;
_tokens.ToNextSignificant();
break;
case TokenType.EndOfObject:
valueWasParsed = false;
parsing = false;
break;
case TokenType.EndOfFile:
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon object. Expected {TokenType.EndOfObject} but found {_tokens.Current.Type} instead.");
default:
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon object. Unexpected token `{_tokens.Current.Type}`.");
}
}
// Consume the closing curly bracket.
_tokens.ToNextSignificant();
}
private void ParseObject(HoconValue owner, bool root, string currentPath)
{
try
{
PushDiagnostics("{");
if (owner.IsObject())
{
//the value of this KVP is already an object
}
else
{
//the value of this KVP is not an object, thus, we should add a new
owner.NewValue(new HoconObject());
}
HoconObject currentObject = owner.GetObject();
while (!_reader.EoF)
{
Token t = _reader.PullNext();
switch (t.Type)
{
case TokenType.Include:
var included = _includeCallback(t.Value);
var substitutions = included.Substitutions;
foreach (var substitution in substitutions)
{
//fixup the substitution, add the current path as a prefix to the substitution path
substitution.Path = currentPath + "." + substitution.Path;
}
_substitutions.AddRange(substitutions);
var otherObj = included.Value.GetObject();
owner.GetObject().Merge(otherObj);
break;
case TokenType.EoF:
if (!string.IsNullOrEmpty(currentPath))
{
throw new HoconParserException(string.Format("Expected end of object but found EoF {0}", GetDiagnosticsStackTrace()));
}
break;
case TokenType.Key:
HoconValue value = currentObject.GetOrCreateKey(t.Value);
var nextPath = currentPath == "" ? t.Value : currentPath + "." + t.Value;
ParseKeyContent(value, nextPath);
if (!root)
{
return;
}
break;
case TokenType.ObjectEnd:
return;
}
}
}
finally
{
PopDiagnostics();
}
}