public void SubstituteRequiredValues_AllowRequiredValueAnyForParameter()
{
// Arrange
var template = "{controller=Home}/{action=Index}/{id?}";
var defaults = new { };
var policies = new { };
var original = RoutePatternFactory.Parse(template, defaults, policies);
var requiredValues = new { controller = RoutePattern.RequiredValueAny, };
// Act
var actual = Transformer.SubstituteRequiredValues(original, requiredValues);
// Assert
Assert.Collection(
actual.Defaults.OrderBy(kvp => kvp.Key),
kvp => Assert.Equal(new KeyValuePair <string, object>("action", "Index"), kvp),
kvp => Assert.Equal(new KeyValuePair <string, object>("controller", "Home"), kvp)); // default is preserved
Assert.Collection(
actual.RequiredValues.OrderBy(kvp => kvp.Key),
kvp => Assert.Equal(new KeyValuePair <string, object>("controller", RoutePattern.RequiredValueAny), kvp));
}
private static bool IsSegmentValid(Context context, List <RoutePatternPart> parts)
{
// If a segment has multiple parts, then it can't contain a catch all.
for (var i = 0; i < parts.Count; i++)
{
var part = parts[i];
if (part is RoutePatternParameterPart parameter && parameter.IsCatchAll && parts.Count > 1)
{
context.Error = Resources.TemplateRoute_CannotHaveCatchAllInMultiSegment;
return(false);
}
}
// if a segment has multiple parts, then only the last one parameter can be optional
// if it is following a optional seperator.
for (var i = 0; i < parts.Count; i++)
{
var part = parts[i];
if (part is RoutePatternParameterPart parameter && parameter.IsOptional && parts.Count > 1)
{
// This optional parameter is the last part in the segment
if (i == parts.Count - 1)
{
var previousPart = parts[i - 1];
if (!previousPart.IsLiteral && !previousPart.IsSeparator)
{
// The optional parameter is preceded by something that is not a literal or separator
// Example of error message:
// "In the segment '{RouteValue}{param?}', the optional parameter 'param' is preceded
// by an invalid segment '{RouteValue}'. Only a period (.) can precede an optional parameter.
context.Error = Resources.FormatTemplateRoute_OptionalParameterCanbBePrecededByPeriod(
RoutePatternPathSegment.DebuggerToString(parts),
parameter.Name,
parts[i - 1].DebuggerToString());
return(false);
}
else if (previousPart is RoutePatternLiteralPart literal && literal.Content != PeriodString)
{
// The optional parameter is preceded by a literal other than period.
// Example of error message:
// "In the segment '{RouteValue}-{param?}', the optional parameter 'param' is preceded
// by an invalid segment '-'. Only a period (.) can precede an optional parameter.
context.Error = Resources.FormatTemplateRoute_OptionalParameterCanbBePrecededByPeriod(
RoutePatternPathSegment.DebuggerToString(parts),
parameter.Name,
parts[i - 1].DebuggerToString());
return(false);
}
parts[i - 1] = RoutePatternFactory.SeparatorPart(((RoutePatternLiteralPart)previousPart).Content);
}
else
{
// This optional parameter is not the last one in the segment
// Example:
// An optional parameter must be at the end of the segment. In the segment '{RouteValue?})',
// optional parameter 'RouteValue' is followed by ')'
context.Error = Resources.FormatTemplateRoute_OptionalParameterHasTobeTheLast(
RoutePatternPathSegment.DebuggerToString(parts),
parameter.Name,
parts[i + 1].DebuggerToString());
return(false);
}
}
}
// A segment cannot contain two consecutive parameters
var isLastSegmentParameter = false;
for (var i = 0; i < parts.Count; i++)
{
var part = parts[i];
if (part.IsParameter && isLastSegmentParameter)
{
context.Error = Resources.TemplateRoute_CannotHaveConsecutiveParameters;
return(false);
}
isLastSegmentParameter = part.IsParameter;
}
return(true);
}
private static bool ParseLiteral(Context context, List <RoutePatternPart> parts)
{
context.Mark();
while (true)
{
if (context.Current == Separator)
{
// End of the segment
break;
}
else if (context.Current == OpenBrace)
{
if (!context.MoveNext())
{
// This is a dangling open-brace, which is not allowed
context.Error = Resources.TemplateRoute_MismatchedParameter;
return(false);
}
if (context.Current == OpenBrace)
{
// This is an 'escaped' brace in a literal, like "{{foo" - keep going.
}
else
{
// We've just seen the start of a parameter, so back up.
context.Back();
break;
}
}
else if (context.Current == CloseBrace)
{
if (!context.MoveNext())
{
// This is a dangling close-brace, which is not allowed
context.Error = Resources.TemplateRoute_MismatchedParameter;
return(false);
}
if (context.Current == CloseBrace)
{
// This is an 'escaped' brace in a literal, like "{{foo" - keep going.
}
else
{
// This is an unbalanced close-brace, which is not allowed
context.Error = Resources.TemplateRoute_MismatchedParameter;
return(false);
}
}
if (!context.MoveNext())
{
break;
}
}
var encoded = context.Capture();
var decoded = encoded.Replace("}}", "}").Replace("{{", "{");
if (IsValidLiteral(context, decoded))
{
parts.Add(RoutePatternFactory.LiteralPart(decoded));
return(true);
}
else
{
return(false);
}
}
private static ConstraintParseResults ParseConstraints(
string text,
string parameterName,
int currentIndex,
int endIndex)
{
var constraints = new List <RoutePatternConstraintReference>();
var state = ParseState.Start;
var startIndex = currentIndex;
do
{
var currentChar = currentIndex > endIndex ? null : (char?)text[currentIndex];
switch (state)
{
case ParseState.Start:
switch (currentChar)
{
case null:
state = ParseState.End;
break;
case ':':
state = ParseState.ParsingName;
startIndex = currentIndex + 1;
break;
case '(':
state = ParseState.InsideParenthesis;
break;
case '=':
state = ParseState.End;
currentIndex--;
break;
}
break;
case ParseState.InsideParenthesis:
switch (currentChar)
{
case null:
state = ParseState.End;
var constraintText = text.Substring(startIndex, currentIndex - startIndex);
constraints.Add(RoutePatternFactory.Constraint(constraintText));
break;
case ')':
// Only consume a ')' token if
// (a) it is the last token
// (b) the next character is the start of the new constraint ':'
// (c) the next character is the start of the default value.
var nextChar = currentIndex + 1 > endIndex ? null : (char?)text[currentIndex + 1];
switch (nextChar)
{
case null:
state = ParseState.End;
constraintText = text.Substring(startIndex, currentIndex - startIndex + 1);
constraints.Add(RoutePatternFactory.Constraint(constraintText));
break;
case ':':
state = ParseState.Start;
constraintText = text.Substring(startIndex, currentIndex - startIndex + 1);
constraints.Add(RoutePatternFactory.Constraint(constraintText));
startIndex = currentIndex + 1;
break;
case '=':
state = ParseState.End;
constraintText = text.Substring(startIndex, currentIndex - startIndex + 1);
constraints.Add(RoutePatternFactory.Constraint(constraintText));
break;
}
break;
case ':':
case '=':
// In the original implementation, the Regex would've backtracked if it encountered an
// unbalanced opening bracket followed by (not necessarily immediatiely) a delimiter.
// Simply verifying that the parantheses will eventually be closed should suffice to
// determine if the terminator needs to be consumed as part of the current constraint
// specification.
var indexOfClosingParantheses = text.IndexOf(')', currentIndex + 1);
if (indexOfClosingParantheses == -1)
{
constraintText = text.Substring(startIndex, currentIndex - startIndex);
constraints.Add(RoutePatternFactory.Constraint(constraintText));
if (currentChar == ':')
{
state = ParseState.ParsingName;
startIndex = currentIndex + 1;
}
else
{
state = ParseState.End;
currentIndex--;
}
}
else
{
currentIndex = indexOfClosingParantheses;
}
break;
}
break;
case ParseState.ParsingName:
switch (currentChar)
{
case null:
state = ParseState.End;
var constraintText = text.Substring(startIndex, currentIndex - startIndex);
if (constraintText.Length > 0)
{
constraints.Add(RoutePatternFactory.Constraint(constraintText));
}
break;
case ':':
constraintText = text.Substring(startIndex, currentIndex - startIndex);
if (constraintText.Length > 0)
{
constraints.Add(RoutePatternFactory.Constraint(constraintText));
}
startIndex = currentIndex + 1;
break;
case '(':
state = ParseState.InsideParenthesis;
break;
case '=':
state = ParseState.End;
constraintText = text.Substring(startIndex, currentIndex - startIndex);
if (constraintText.Length > 0)
{
constraints.Add(RoutePatternFactory.Constraint(constraintText));
}
currentIndex--;
break;
}
break;
}
currentIndex++;
} while (state != ParseState.End);
return(new ConstraintParseResults(currentIndex, constraints));
}
