private static bool IsMinificationHint(ConstantWrapper node)
{
var isHint = false;
if (node.PrimitiveType == PrimitiveType.String)
{
// try splitting on commas and removing empty items
var sections = node.ToString().Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
foreach (var section in sections)
{
// valid hints are:
// name:nomunge don't automatically rename the field defined in this scope named "name"
// if name is missing (colon is the first character) or "*", then don't rename ANY
// fields defined in the current scope.
var ndxColon = section.IndexOf(':');
if (ndxColon >= 0)
{
// make sure this is a "nomunge" hint. If it is, then the entire node is treated as a hint and
// will be removed from the AST.
if (string.Compare(section.Substring(ndxColon + 1).Trim(), "nomunge", StringComparison.OrdinalIgnoreCase) == 0)
{
// it is.
isHint = true;
// get the name that we don't want to munge. Null means all. Convert "*"
// to null.
var identifier = section.Substring(0, ndxColon).Trim();
if (string.IsNullOrEmpty(identifier) || string.CompareOrdinal(identifier, "*") == 0)
{
identifier = null;
}
// get the current scope and iterate over all the fields within it
// looking for just the ones that are defined here (outer is null)
var currentScope = node.EnclosingScope;
foreach (var field in currentScope.NameTable.Values)
{
if (field.OuterField == null)
{
// if the identifier is null or matches exactly, mark it as not crunchable
if (identifier == null || string.CompareOrdinal(identifier, field.Name) == 0)
{
field.CanCrunch = false;
}
}
}
}
}
}
}
return(isHint);
}
private static bool IsMinificationHint(ConstantWrapper node)
{
var isHint = false;
if (node.PrimitiveType == PrimitiveType.String)
{
// try splitting on commas and removing empty items
var sections = node.ToString().Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
foreach (var section in sections)
{
// valid hints are:
// name:nomunge don't automatically rename the field defined in this scope named "name"
// if name is missing (colon is the first character) or "*", then don't rename ANY
// fields defined in the current scope.
var ndxColon = section.IndexOf(':');
if (ndxColon >= 0)
{
// make sure this is a "nomunge" hint. If it is, then the entire node is treated as a hint and
// will be removed from the AST.
if (string.Compare(section.Substring(ndxColon + 1).Trim(), "nomunge", StringComparison.OrdinalIgnoreCase) == 0)
{
// it is.
isHint = true;
// get the name that we don't want to munge. Null means all. Convert "*"
// to null.
var identifier = section.Substring(0, ndxColon).Trim();
if (string.IsNullOrEmpty(identifier) || string.CompareOrdinal(identifier, "*") == 0)
{
identifier = null;
}
// get the current scope and iterate over all the fields within it
// looking for just the ones that are defined here (outer is null)
var currentScope = node.EnclosingScope;
foreach (var field in currentScope.NameTable.Values)
{
if (field.OuterField == null)
{
// if the identifier is null or matches exactly, mark it as not crunchable
if (identifier == null || string.CompareOrdinal(identifier, field.Name) == 0)
{
field.CanCrunch = false;
}
}
}
}
}
}
}
return isHint;
}
/// <summary>
/// If the new literal is a string literal, then we need to check to see if our
/// parent is a CallNode. If it is, and if the string literal can be an identifier,
/// we'll replace it with a Member-Dot operation.
/// </summary>
/// <param name="newLiteral">newLiteral we intend to replace this binaryop node with</param>
/// <returns>true if we replaced the parent callnode with a member-dot operation</returns>
private bool ReplaceMemberBracketWithDot(BinaryOperator node, ConstantWrapper newLiteral)
{
if (newLiteral.IsStringLiteral)
{
// see if this newly-combined string is the sole argument to a
// call-brackets node. If it is and the combined string is a valid
// identifier (and not a keyword), then we can replace the call
// with a member operator.
// remember that the parent of the argument won't be the call node -- it
// will be the ast node list representing the arguments, whose parent will
// be the node list.
CallNode parentCall = (node.Parent is AstNodeList ? node.Parent.Parent as CallNode : null);
if (parentCall != null && parentCall.InBrackets)
{
// get the newly-combined string
string combinedString = newLiteral.ToString();
// see if this new string is the target of a replacement operation
string newName;
if (m_parser.Settings.HasRenamePairs && m_parser.Settings.ManualRenamesProperties
&& m_parser.Settings.IsModificationAllowed(TreeModifications.PropertyRenaming)
&& !string.IsNullOrEmpty(newName = m_parser.Settings.GetNewName(combinedString)))
{
// yes, it is. Now see if the new name is safe to be converted to a dot-operation.
if (m_parser.Settings.IsModificationAllowed(TreeModifications.BracketMemberToDotMember)
&& JSScanner.IsSafeIdentifier(newName)
&& !JSScanner.IsKeyword(newName, parentCall.EnclosingScope.UseStrict))
{
// we want to replace the call with operator with a new member dot operation, and
// since we won't be analyzing it (we're past the analyze phase, we're going to need
// to use the new string value
Member replacementMember = new Member(parentCall.Context, m_parser)
{
Root = parentCall.Function,
Name = newName,
NameContext = parentCall.Arguments[0].Context
};
parentCall.Parent.ReplaceChild(parentCall, replacementMember);
return true;
}
else
{
// nope, can't be changed to a dot-operator for whatever reason.
// just replace the value on this new literal. The old operation will
// get replaced with this new literal
newLiteral.Value = newName;
// and make sure it's type is string
newLiteral.PrimitiveType = PrimitiveType.String;
}
}
else if (m_parser.Settings.IsModificationAllowed(TreeModifications.BracketMemberToDotMember))
{
// our parent is a call-bracket -- now we just need to see if the newly-combined
// string can be an identifier
if (JSScanner.IsSafeIdentifier(combinedString) && !JSScanner.IsKeyword(combinedString, parentCall.EnclosingScope.UseStrict))
{
// yes -- replace the parent call with a new member node using the newly-combined string
Member replacementMember = new Member(parentCall.Context, m_parser)
{
Root = parentCall.Function,
Name = combinedString,
NameContext = parentCall.Arguments[0].Context
};
parentCall.Parent.ReplaceChild(parentCall, replacementMember);
return true;
}
}
}
}
return false;
}
private static string ComputeJoin(ArrayLiteral arrayLiteral, ConstantWrapper separatorNode)
{
// if the separator node is null, then the separator is a single comma character.
// otherwise it's just the string value of the separator.
var separator = separatorNode == null ? "," : separatorNode.ToString();
var sb = new StringBuilder();
for (var ndx = 0; ndx < arrayLiteral.Elements.Count; ++ndx)
{
// add the separator between items (if we have one)
if (ndx > 0 && !string.IsNullOrEmpty(separator))
{
sb.Append(separator);
}
// the element is a constant wrapper (we wouldn't get this far if it wasn't),
// but we've overloaded the virtual ToString method on ConstantWrappers to convert the
// constant value to a string value.
sb.Append(arrayLiteral.Elements[ndx].ToString());
}
return sb.ToString();
}
private ConstantWrapper StrictNotEqual(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
if (m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
PrimitiveType leftType = left.PrimitiveType;
if (leftType == right.PrimitiveType)
{
// the values are the same type
switch (leftType)
{
case PrimitiveType.Null:
// null !== null is false
newLiteral = new ConstantWrapper(false, PrimitiveType.Boolean, null, m_parser);
break;
case PrimitiveType.Boolean:
// compare boolean values
newLiteral = new ConstantWrapper(left.ToBoolean() != right.ToBoolean(), PrimitiveType.Boolean, null, m_parser);
break;
case PrimitiveType.String:
// compare string ordinally
if (left.IsOkayToCombine && right.IsOkayToCombine)
{
newLiteral = new ConstantWrapper(string.CompareOrdinal(left.ToString(), right.ToString()) != 0, PrimitiveType.Boolean, null, m_parser);
}
break;
case PrimitiveType.Number:
try
{
// compare the values
// +0 and -0 are treated as "equal" in C#, so we don't need to test them separately.
// and NaN is always unequal to everything else, including itself.
if (left.IsOkayToCombine && right.IsOkayToCombine)
{
newLiteral = new ConstantWrapper(left.ToNumber() != right.ToNumber(), PrimitiveType.Boolean, null, m_parser);
}
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
break;
}
}
else
{
// if they aren't the same type, they are not equal
newLiteral = new ConstantWrapper(true, PrimitiveType.Boolean, null, m_parser);
}
}
return newLiteral;
}
private ConstantWrapper GreaterThanOrEqual(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
if (m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
if (left.IsStringLiteral && right.IsStringLiteral)
{
if (left.IsOkayToCombine && right.IsOkayToCombine)
{
// do a straight ordinal comparison of the strings
newLiteral = new ConstantWrapper(string.CompareOrdinal(left.ToString(), right.ToString()) >= 0, PrimitiveType.Boolean, null, m_parser);
}
}
else
{
try
{
// either one or both are NOT a string -- numeric comparison
if (left.IsOkayToCombine && right.IsOkayToCombine)
{
newLiteral = new ConstantWrapper(left.ToNumber() >= right.ToNumber(), PrimitiveType.Boolean, null, m_parser);
}
}
catch (InvalidCastException)
{
// some kind of casting in ToNumber caused a situation where we don't want
// to perform the combination on these operands
}
}
}
return newLiteral;
}
private ConstantWrapper StringConcat(ConstantWrapper left, ConstantWrapper right)
{
ConstantWrapper newLiteral = null;
// if we don't want to combine adjacent string literals, then we know we don't want to do
// anything here.
if (m_parser.Settings.IsModificationAllowed(TreeModifications.CombineAdjacentStringLiterals))
{
// if either one of the operands is not a string literal, then check to see if we allow
// evaluation of numeric expression; if not, then no-go. IF they are both string literals,
// then it doesn't matter what the numeric flag says.
if ((left.IsStringLiteral && right.IsStringLiteral)
|| m_parser.Settings.IsModificationAllowed(TreeModifications.EvaluateNumericExpressions))
{
// if either value is a floating-point number (a number, not NaN, not Infinite, not an Integer),
// then we won't do the string concatenation because different browsers may have subtle differences
// in their double-to-string conversion algorithms.
// so if neither is a numeric literal, or if one or both are, if they are both integer literals
// in the range that we can EXACTLY represent them in a double, then we can proceed.
// NaN, +Infinity and -Infinity are also acceptable
if (left.IsOkayToCombine && right.IsOkayToCombine)
{
newLiteral = new ConstantWrapper(left.ToString() + right.ToString(), PrimitiveType.String, null, m_parser);
}
}
}
return newLiteral;
}
