internal void ResolveValue(HoconSubstitution child)
{
if (child.Type == HoconType.Empty)
{
Remove(child);
}
else
{
if (Type == HoconType.Empty)
{
Type = child.Type;
}
else if (Type != child.Type)
{
throw HoconParserException.Create(child, child.Path,
"Invalid substitution, substituted type must match its sibling type. " +
$"Sibling type:{Type}, substitution type:{child.Type}");
}
}
switch (Parent)
{
case HoconField v:
v.ResolveValue(this);
break;
case HoconArray a:
a.ResolveValue(child);
break;
default:
throw new Exception($"Invalid parent type while resolving substitution:{Parent.GetType()}");
}
}
private HoconArray ParsePlusEqualAssignArray(IHoconElement owner)
{
// sanity check
if (_tokens.Current.Type != TokenType.PlusEqualAssign)
{
throw HoconParserException.Create(_tokens.Current, Path,
"Failed to parse Hocon field with += operator. " +
$"Expected {TokenType.PlusEqualAssign}, found {{_tokens.Current.Type}} instead.");
}
var currentArray = new HoconArray(owner);
// consume += operator token
ConsumeWhitelines();
switch (_tokens.Current.Type)
{
case TokenType.Include:
currentArray.Add(ParseInclude(currentArray));
break;
case TokenType.StartOfArray:
// Array inside of arrays are parsed as values because it can be value concatenated with another array.
currentArray.Add(ParseValue(currentArray));
break;
case TokenType.StartOfObject:
currentArray.Add(ParseObject(currentArray));
break;
case TokenType.LiteralValue:
if (_tokens.Current.IsNonSignificant())
{
ConsumeWhitelines();
}
if (_tokens.Current.Type != TokenType.LiteralValue)
{
break;
}
currentArray.Add(ParseValue(currentArray));
break;
case TokenType.SubstituteOptional:
case TokenType.SubstituteRequired:
var pointerPath = HoconPath.Parse(_tokens.Current.Value);
HoconSubstitution sub = new HoconSubstitution(currentArray, pointerPath, _tokens.Current,
_tokens.Current.Type == TokenType.SubstituteRequired);
_substitutions.Add(sub);
currentArray.Add(sub);
_tokens.Next();
break;
default:
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon array. Expected {TokenType.EndOfArray} but found {_tokens.Current.Type} instead.");
}
return(currentArray);
}
internal void ResolveValue(HoconSubstitution child)
{
var index = IndexOf(child);
Remove(child);
if (child.Type != HoconType.Empty)
{
if (Type == HoconType.Empty)
{
Type = child.Type;
}
else if (!Type.IsMergeable(child.Type))
{
throw HoconParserException.Create(child, child.Path,
"Invalid substitution, substituted type be must be mergeable with its sibling type. " +
$"Sibling type:{Type}, substitution type:{child.Type}");
}
var clonedValue = (HoconValue)child.ResolvedValue.Clone(Parent);
switch (Type)
{
case HoconType.Object:
Insert(index, clonedValue.GetObject());
break;
case HoconType.Array:
var hoconArray = new HoconArray(this);
hoconArray.AddRange(clonedValue.GetArray());
Insert(index, hoconArray);
break;
case HoconType.Boolean:
case HoconType.Number:
case HoconType.String:
var elementList = new List <IHoconElement>();
foreach (var element in clonedValue)
{
elementList.Add(element);
}
InsertRange(index, elementList);
break;
}
}
switch (Parent)
{
case HoconField v:
v.ResolveValue(this);
break;
case HoconArray a:
a.ResolveValue(child);
break;
default:
throw new Exception($"Invalid parent type while resolving substitution:{Parent.GetType()}");
}
}
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);
}
internal void ResolveValue(HoconSubstitution sub)
{
if (sub.Type == HoconType.Empty)
{
Remove(sub);
return;
}
if (sub.Type != HoconType.Array)
{
throw HoconParserException.Create(sub, sub.Path,
$"Substitution value must match the rest of the field type or empty. Parent value type: {Type}, substitution type: {sub.Type}");
}
}
internal void ResolveValue(HoconSubstitution sub)
{
var subValue = (HoconValue)sub.Parent;
if (sub.Type == HoconType.Empty)
{
subValue.Remove(sub);
if (subValue.Count == 0)
{
Remove(subValue);
}
return;
}
if (_arrayType != HoconType.Empty && sub.Type != _arrayType)
{
throw HoconParserException.Create(sub, sub.Path,
$"Substitution value must match the rest of the field type or empty. Array value type: {_arrayType}, substitution type: {sub.Type}");
}
}
/// <summary>
/// Retrieves the next value token from the tokenizer and appends it
/// to the supplied element <paramref name="owner" />.
/// </summary>
/// <param name="owner">The element to append the next token.</param>
/// <exception cref="System.Exception">End of file reached while trying to read a value</exception>
private HoconValue ParseValue(IHoconElement owner)
{
// value is lazy initialized because we don't know what kind of value we're parsing
HoconValue value = null;
var parsing = true;
while (parsing)
{
switch (_tokens.Current.Type)
{
case TokenType.Include:
var includeToken = _tokens.Current;
var includeValue = ParseInclude();
switch (includeValue.Type)
{
case HoconType.Empty:
value = new HoconEmptyValue(owner);
break;
case HoconType.Object:
value = GetHoconValueFromParentElement(owner, TokenType.StartOfObject);
value.ReParent(includeValue);
break;
case HoconType.Array:
value = GetHoconValueFromParentElement(owner, TokenType.StartOfArray);
value.ReParent(includeValue);
break;
default:
throw HoconParserException.Create(includeToken, Path,
"Include could never contain a literal type.");
}
break;
case TokenType.LiteralValue:
// Consume leading whitespaces.
if (_tokens.Current.IsNonSignificant())
{
_tokens.ToNextSignificant();
}
if (_tokens.Current.Type != TokenType.LiteralValue)
{
break;
}
if (value == null)
{
value = GetHoconValueFromParentElement(owner, _tokens.Current.Type);
}
while (_tokens.Current.Type == TokenType.LiteralValue)
{
value.Add(HoconLiteral.Create(value, _tokens.Current));
_tokens.Next();
}
break;
case TokenType.StartOfObject:
if (value == null)
{
value = GetHoconValueFromParentElement(owner, _tokens.Current.Type);
}
ParseObject(ref value);
break;
case TokenType.StartOfArray:
if (value == null)
{
value = GetHoconValueFromParentElement(owner, _tokens.Current.Type);
}
// If this array is already initialized, we are going to overwrite it
if (value.Type == HoconType.Array && value.Count > 0)
{
value.Clear();
}
value.Add(ParseArray(value));
break;
case TokenType.SubstituteOptional:
case TokenType.SubstituteRequired:
if (value == null)
{
value = new HoconValue(owner);
}
var pointerPath = HoconPath.Parse(_tokens.Current.Value);
var sub = new HoconSubstitution(value, pointerPath, _tokens.Current,
_tokens.Current.Type == TokenType.SubstituteRequired);
_substitutions.Add(sub);
_tokens.Next();
value.Add(sub);
break;
case TokenType.PlusEqualAssign:
if (value == null)
{
value = new HoconValue(owner);
}
var subAssign = new HoconSubstitution(value, new HoconPath(Path), _tokens.Current, false);
_substitutions.Add(subAssign);
value.Add(subAssign);
value.Add(ParsePlusEqualAssignArray(value));
parsing = false;
break;
case TokenType.EndOfObject:
case TokenType.EndOfArray:
parsing = false;
break;
case TokenType.Comment:
_tokens.ToNextSignificant();
break;
case TokenType.EndOfLine:
parsing = false;
break;
case TokenType.EndOfFile:
case TokenType.Comma:
parsing = false;
break;
case TokenType.Assign:
// Special case to support end of line after assign
_tokens.ToNextSignificantLine();
break;
default:
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon value. Unexpected token: `{_tokens.Current.Type}`");
}
}
if (value == null)
{
value = new HoconEmptyValue(owner);
}
// trim trailing whitespace if result is a literal
if (value.Type.IsLiteral())
{
if (value[value.Count - 1] is HoconWhitespace)
{
value.RemoveAt(value.Count - 1);
}
}
return(value);
}
private bool IsValueCyclic(HoconField field, HoconSubstitution sub)
{
var pendingValues = new Stack <HoconValue>();
var visitedFields = new List <HoconField> {
field
};
var pendingSubs = new Stack <HoconSubstitution>();
pendingSubs.Push(sub);
while (pendingSubs.Count > 0)
{
var currentSub = pendingSubs.Pop();
if (!_root.GetObject().TryGetField(currentSub.Path, out var currentField))
{
continue;
}
if (visitedFields.Contains(currentField))
{
return(true);
}
visitedFields.Add(currentField);
pendingValues.Push(currentField.Value);
while (pendingValues.Count > 0)
{
var currentValue = pendingValues.Pop();
foreach (var value in currentValue)
{
switch (value)
{
case HoconLiteral _:
break;
case HoconObject o:
foreach (var f in o.Values)
{
if (visitedFields.Contains(f))
{
return(true);
}
visitedFields.Add(f);
pendingValues.Push(f.Value);
}
break;
case HoconArray a:
foreach (var item in a.GetArray())
{
pendingValues.Push(item);
}
break;
case HoconSubstitution s:
pendingSubs.Push(s);
break;
}
}
}
}
return(false);
}
/// <summary>
/// Retrieves the next value token from the tokenizer and appends it
/// to the supplied element <paramref name="owner"/>.
/// </summary>
/// <param name="owner">The element to append the next token.</param>
/// <exception cref="System.Exception">End of file reached while trying to read a value</exception>
public void ParseValue(HoconValue owner, string currentPath)
{
if (_reader.EoF)
{
throw new HoconParserException("End of file reached while trying to read a value");
}
_reader.PullWhitespaceAndComments();
var start = _reader.Index;
try
{
while (_reader.IsValue())
{
Token t = _reader.PullValue();
switch (t.Type)
{
case TokenType.EoF:
break;
case TokenType.LiteralValue:
if (owner.IsObject())
{
//needed to allow for override objects
owner.Clear();
}
var lit = new HoconLiteral
{
Value = t.Value
};
owner.AppendValue(lit);
break;
case TokenType.ObjectStart:
ParseObject(owner, true, currentPath);
break;
case TokenType.ArrayStart:
HoconArray arr = ParseArray(currentPath);
owner.AppendValue(arr);
break;
case TokenType.Substitute:
HoconSubstitution sub = ParseSubstitution(t.Value);
_substitutions.Add(sub);
owner.AppendValue(sub);
break;
}
if (_reader.IsSpaceOrTab())
{
ParseTrailingWhitespace(owner);
}
}
IgnoreComma();
}
catch (HoconTokenizerException tokenizerException)
{
throw new HoconParserException(string.Format("{0}\r{1}", tokenizerException.Message, GetDiagnosticsStackTrace()), tokenizerException);
}
finally
{
//no value was found, tokenizer is still at the same position
if (_reader.Index == start)
{
throw new HoconParserException(string.Format("Hocon syntax error {0}\r{1}", _reader.GetHelpTextAtIndex(start), GetDiagnosticsStackTrace()));
}
}
}
/// <summary>
/// Retrieves the next array token from the tokenizer.
/// </summary>
/// <returns>An array of elements retrieved from the token.</returns>
private HoconArray ParseArray(IHoconElement owner)
{
var currentArray = new HoconArray(owner);
// consume start of array token
ConsumeWhitelines();
IHoconElement lastValue = null;
var parsing = true;
while (parsing)
{
switch (_tokens.Current.Type)
{
case TokenType.Include:
if (lastValue != null)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon array. Expected `{TokenType.Comma}` or `{TokenType.EndOfLine}, " +
$"found `{_tokens.Current.Type}` instead.");
}
lastValue = ParseInclude(currentArray);
break;
case TokenType.StartOfArray:
if (lastValue != null)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon array. Expected `{TokenType.Comma}` or `{TokenType.EndOfLine}, " +
$"found `{_tokens.Current.Type}` instead.");
}
// Array inside of arrays are parsed as values because it can be value concatenated with another array.
lastValue = ParseValue(currentArray);
break;
case TokenType.StartOfObject:
if (lastValue != null)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon array. Expected `{TokenType.Comma}` or `{TokenType.EndOfLine}, " +
$"found `{_tokens.Current.Type}` instead.");
}
lastValue = ParseObject(currentArray);
break;
case TokenType.LiteralValue:
if (_tokens.Current.IsNonSignificant())
{
ConsumeWhitelines();
}
if (_tokens.Current.Type != TokenType.LiteralValue)
{
break;
}
if (lastValue != null)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon array. Expected `{TokenType.Comma}` or `{TokenType.EndOfLine}, " +
$"found `{_tokens.Current.Type}` instead.");
}
lastValue = ParseValue(currentArray);
break;
case TokenType.SubstituteOptional:
case TokenType.SubstituteRequired:
if (lastValue != null)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon array. Expected `{TokenType.Comma}` or `{TokenType.EndOfLine}, " +
$"found `{_tokens.Current.Type}` instead.");
}
var pointerPath = HoconPath.Parse(_tokens.Current.Value);
HoconSubstitution sub = new HoconSubstitution(currentArray, pointerPath, _tokens.Current,
_tokens.Current.Type == TokenType.SubstituteRequired);
_substitutions.Add(sub);
lastValue = sub;
_tokens.Next();
break;
case TokenType.Comment:
case TokenType.EndOfLine:
if (lastValue == null)
{
ConsumeWhitelines();
break;
}
switch (lastValue.Type)
{
case HoconType.Array:
currentArray.Add(lastValue);
break;
default:
currentArray.Add(lastValue);
break;
}
lastValue = null;
ConsumeWhitelines();
break;
case TokenType.Comma:
if (lastValue == null)
{
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon array. Expected a valid value, found `{_tokens.Current.Type}` instead.");
}
switch (lastValue.Type)
{
case HoconType.Array:
currentArray.Add(lastValue);
break;
default:
currentArray.Add(lastValue);
break;
}
lastValue = null;
ConsumeWhitelines();
break;
case TokenType.EndOfArray:
if (lastValue != null)
{
switch (lastValue.Type)
{
case HoconType.Array:
currentArray.Add(lastValue);
break;
default:
currentArray.Add(lastValue);
break;
}
lastValue = null;
}
parsing = false;
break;
default:
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon array. Expected {TokenType.EndOfArray} but found {_tokens.Current.Type} instead.");
}
}
// Consume end of array token
_tokens.Next();
return(currentArray);
}
/// <summary>
/// Retrieves the next value token from the tokenizer and appends it
/// to the supplied element <paramref name="owner"/>.
/// </summary>
/// <param name="owner">The element to append the next token.</param>
/// <exception cref="System.Exception">End of file reached while trying to read a value</exception>
private HoconValue ParseValue(IHoconElement owner)
{
var value = new HoconValue(owner);
var parsing = true;
while (parsing)
{
switch (_tokens.Current.Type)
{
case TokenType.Include:
value.Add(ParseInclude(value));
break;
case TokenType.LiteralValue:
// Consume leading whitespaces.
if (_tokens.Current.IsNonSignificant())
{
ConsumeWhitespace();
}
if (_tokens.Current.Type != TokenType.LiteralValue)
{
break;
}
while (_tokens.Current.Type == TokenType.LiteralValue)
{
value.Add(HoconLiteral.Create(value, _tokens.Current));
_tokens.Next();
}
break;
case TokenType.StartOfObject:
value.Add(ParseObject(value));
break;
case TokenType.StartOfArray:
value.Add(ParseArray(value));
break;
case TokenType.SubstituteOptional:
case TokenType.SubstituteRequired:
var pointerPath = HoconPath.Parse(_tokens.Current.Value);
HoconSubstitution sub = new HoconSubstitution(value, pointerPath, _tokens.Current,
_tokens.Current.Type == TokenType.SubstituteRequired);
_substitutions.Add(sub);
value.Add(sub);
_tokens.Next();
break;
case TokenType.EndOfObject:
case TokenType.EndOfArray:
parsing = false;
break;
// comments automatically stop value parsing.
case TokenType.Comment:
ConsumeWhitelines();
parsing = false;
break;
case TokenType.EndOfLine:
parsing = false;
break;
case TokenType.EndOfFile:
case TokenType.Comma:
parsing = false;
break;
case TokenType.PlusEqualAssign:
HoconSubstitution subAssign = new HoconSubstitution(value, new HoconPath(Path), _tokens.Current, false);
_substitutions.Add(subAssign);
value.Add(subAssign);
value.Add(ParsePlusEqualAssignArray(value));
parsing = false;
break;
case TokenType.Assign:
ConsumeWhitelines();
break;
default:
throw HoconParserException.Create(_tokens.Current, Path,
$"Failed to parse Hocon value. Unexpected token: `{_tokens.Current.Type}`");
}
}
// trim trailing whitespace if result is a literal
if (value.Type == HoconType.Literal)
{
if (value[value.Count - 1] is HoconWhitespace)
{
value.RemoveAt(value.Count - 1);
}
}
return(value);
}
