public void Run(AstNode compilationUnit)
{
if (!context.Settings.QueryExpressions)
{
return;
}
DecompileQueries(compilationUnit);
// After all queries were decompiled, detect degenerate queries (queries not property terminated with 'select' or 'group')
// and fix them, either by adding a degenerate select, or by combining them with another query.
foreach (QueryExpression query in compilationUnit.Descendants.OfType <QueryExpression>())
{
QueryFromClause fromClause = (QueryFromClause)query.Clauses.First();
if (IsDegenerateQuery(query))
{
// introduce select for degenerate query
query.Clauses.Add(new QuerySelectClause {
Expression = IdentifierExpression.Create(fromClause.Identifier, fromClause.IdentifierToken.Annotation <object>())
});
}
// See if the data source of this query is a degenerate query,
// and combine the queries if possible.
QueryExpression innerQuery = fromClause.Expression as QueryExpression;
while (IsDegenerateQuery(innerQuery))
{
QueryFromClause innerFromClause = (QueryFromClause)innerQuery.Clauses.First();
if (fromClause.Identifier != innerFromClause.Identifier)
{
break;
}
// Replace the fromClause with all clauses from the inner query
fromClause.Remove();
QueryClause insertionPos = null;
foreach (var clause in innerQuery.Clauses)
{
query.Clauses.InsertAfter(insertionPos, insertionPos = clause.Detach());
}
fromClause = innerFromClause;
innerQuery = fromClause.Expression as QueryExpression;
}
}
}
/// <summary>
/// Removes all occurrences of transparent identifiers
/// </summary>
void RemoveTransparentIdentifierReferences(AstNode node)
{
foreach (AstNode child in node.Children)
{
RemoveTransparentIdentifierReferences(child);
}
MemberReferenceExpression mre = node as MemberReferenceExpression;
if (mre != null)
{
IdentifierExpression ident = mre.Target as IdentifierExpression;
if (ident != null && IsTransparentIdentifier(ident.Identifier))
{
IdentifierExpression newIdent = IdentifierExpression.Create(mre.MemberName, mre.MemberNameToken.Annotation <object>());
mre.TypeArguments.MoveTo(newIdent.TypeArguments);
newIdent.CopyAnnotationsFrom(mre);
newIdent.RemoveAnnotations <PropertyDeclaration>(); // remove the reference to the property of the anonymous type
mre.ReplaceWith(newIdent);
return;
}
}
}
Expression Convert(Expression expr)
{
InvocationExpression invocation = expr as InvocationExpression;
if (invocation != null)
{
IMethod mr = invocation.Annotation <IMethod>();
if (mr != null && mr.DeclaringType != null && mr.DeclaringType.FullName == "System.Linq.Expressions.Expression")
{
switch (mr.Name)
{
case "Add":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.Add, false));
case "AddChecked":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.Add, true));
case "AddAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.Add, false));
case "AddAssignChecked":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.Add, true));
case "And":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.BitwiseAnd));
case "AndAlso":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.ConditionalAnd));
case "AndAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.BitwiseAnd));
case "ArrayAccess":
case "ArrayIndex":
return(ConvertArrayIndex(invocation));
case "ArrayLength":
return(ConvertArrayLength(invocation));
case "Assign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.Assign));
case "Call":
return(ConvertCall(invocation));
case "Coalesce":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.NullCoalescing));
case "Condition":
return(ConvertCondition(invocation));
case "Constant":
if (invocation.Arguments.Count >= 1)
{
return(invocation.Arguments.First().Clone());
}
else
{
return(NotSupported(expr));
}
case "Convert":
return(ConvertCast(invocation, false));
case "ConvertChecked":
return(ConvertCast(invocation, true));
case "Divide":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.Divide));
case "DivideAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.Divide));
case "Equal":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.Equality));
case "ExclusiveOr":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.ExclusiveOr));
case "ExclusiveOrAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.ExclusiveOr));
case "Field":
return(ConvertField(invocation));
case "GreaterThan":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.GreaterThan));
case "GreaterThanOrEqual":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.GreaterThanOrEqual));
case "Invoke":
return(ConvertInvoke(invocation));
case "Lambda":
return(ConvertLambda(invocation));
case "LeftShift":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.ShiftLeft));
case "LeftShiftAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.ShiftLeft));
case "LessThan":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.LessThan));
case "LessThanOrEqual":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.LessThanOrEqual));
case "ListInit":
return(ConvertListInit(invocation));
case "MemberInit":
return(ConvertMemberInit(invocation));
case "Modulo":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.Modulus));
case "ModuloAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.Modulus));
case "Multiply":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.Multiply, false));
case "MultiplyChecked":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.Multiply, true));
case "MultiplyAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.Multiply, false));
case "MultiplyAssignChecked":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.Multiply, true));
case "Negate":
return(ConvertUnaryOperator(invocation, UnaryOperatorType.Minus, false));
case "NegateChecked":
return(ConvertUnaryOperator(invocation, UnaryOperatorType.Minus, true));
case "New":
return(ConvertNewObject(invocation));
case "NewArrayBounds":
return(ConvertNewArrayBounds(invocation));
case "NewArrayInit":
return(ConvertNewArrayInit(invocation));
case "Not":
return(ConvertUnaryOperator(invocation, UnaryOperatorType.Not));
case "NotEqual":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.InEquality));
case "OnesComplement":
return(ConvertUnaryOperator(invocation, UnaryOperatorType.BitNot));
case "Or":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.BitwiseOr));
case "OrAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.BitwiseOr));
case "OrElse":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.ConditionalOr));
case "Property":
return(ConvertProperty(invocation));
case "Quote":
if (invocation.Arguments.Count == 1)
{
return(Convert(invocation.Arguments.Single()));
}
else
{
return(NotSupported(invocation));
}
case "RightShift":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.ShiftRight));
case "RightShiftAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.ShiftRight));
case "Subtract":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.Subtract, false));
case "SubtractChecked":
return(ConvertBinaryOperator(invocation, BinaryOperatorType.Subtract, true));
case "SubtractAssign":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.Subtract, false));
case "SubtractAssignChecked":
return(ConvertAssignmentOperator(invocation, AssignmentOperatorType.Subtract, true));
case "TypeAs":
return(ConvertTypeAs(invocation));
case "TypeIs":
return(ConvertTypeIs(invocation));
}
}
}
IdentifierExpression ident = expr as IdentifierExpression;
if (ident != null)
{
ILVariable v = ident.Annotation <ILVariable>();
if (v != null)
{
foreach (LambdaExpression lambda in activeLambdas)
{
foreach (ParameterDeclaration p in lambda.Parameters)
{
if (p.Annotation <ILVariable>() == v)
{
return(IdentifierExpression.Create(p.Name, v.IsParameter ? TextTokenKind.Parameter : TextTokenKind.Local).WithAnnotation(v));
}
}
}
}
}
return(NotSupported(expr));
}
public override object VisitBlockStatement(BlockStatement blockStatement, object data)
{
int numberOfVariablesOutsideBlock = currentlyUsedVariableNames.Count;
base.VisitBlockStatement(blockStatement, data);
foreach (ExpressionStatement stmt in blockStatement.Statements.OfType <ExpressionStatement>().ToArray())
{
Match displayClassAssignmentMatch = displayClassAssignmentPattern.Match(stmt);
if (!displayClassAssignmentMatch.Success)
{
continue;
}
ILVariable variable = displayClassAssignmentMatch.Get <AstNode>("variable").Single().Annotation <ILVariable>();
if (variable == null)
{
continue;
}
TypeDef type = variable.Type.ToTypeDefOrRef().ResolveWithinSameModule();
if (!IsPotentialClosure(context, type))
{
continue;
}
if (displayClassAssignmentMatch.Get <AstType>("type").Single().Annotation <ITypeDefOrRef>().ResolveWithinSameModule() != type)
{
continue;
}
// Looks like we found a display class creation. Now let's verify that the variable is used only for field accesses:
bool ok = true;
foreach (var identExpr in blockStatement.Descendants.OfType <IdentifierExpression>())
{
if (identExpr.Identifier == variable.Name && identExpr != displayClassAssignmentMatch.Get("variable").Single())
{
if (!(identExpr.Parent is MemberReferenceExpression && identExpr.Parent.Annotation <IField>() != null && identExpr.Parent.Annotation <IField>().IsField))
{
ok = false;
}
}
}
if (!ok)
{
continue;
}
Dictionary <IField, AstNode> dict = new Dictionary <IField, AstNode>();
// Delete the variable declaration statement:
VariableDeclarationStatement displayClassVarDecl = PatternStatementTransform.FindVariableDeclaration(stmt, variable.Name);
if (displayClassVarDecl != null)
{
displayClassVarDecl.Remove(); //TODO: Save ILRanges
}
// Delete the assignment statement:
AstNode cur = stmt.NextSibling;
stmt.Remove(); //TODO: Save ILRanges
// Delete any following statements as long as they assign parameters to the display class
BlockStatement rootBlock = blockStatement.Ancestors.OfType <BlockStatement>().LastOrDefault() ?? blockStatement;
List <ILVariable> parameterOccurrances = rootBlock.Descendants.OfType <IdentifierExpression>()
.Select(n => n.Annotation <ILVariable>()).Where(p => p != null && p.IsParameter).ToList();
AstNode next;
for (; cur != null; cur = next)
{
next = cur.NextSibling;
// Test for the pattern:
// "variableName.MemberName = right;"
ExpressionStatement closureFieldAssignmentPattern = new ExpressionStatement(
new AssignmentExpression(
new NamedNode("left", new MemberReferenceExpression {
Target = IdentifierExpression.Create(variable.Name, variable.IsParameter ? TextTokenType.Parameter : TextTokenType.Local),
MemberName = Pattern.AnyString
}),
new AnyNode("right")
)
);
Match m = closureFieldAssignmentPattern.Match(cur);
if (m.Success)
{
FieldDef fieldDef = m.Get <MemberReferenceExpression>("left").Single().Annotation <IField>().ResolveFieldWithinSameModule();
AstNode right = m.Get <AstNode>("right").Single();
bool isParameter = false;
bool isDisplayClassParentPointerAssignment = false;
if (right is ThisReferenceExpression)
{
isParameter = true;
}
else if (right is IdentifierExpression)
{
// handle parameters only if the whole method contains no other occurrence except for 'right'
ILVariable v = right.Annotation <ILVariable>();
isParameter = v.IsParameter && parameterOccurrances.Count(c => c == v) == 1;
if (!isParameter && IsPotentialClosure(context, v.Type.ToTypeDefOrRef().ResolveWithinSameModule()))
{
// parent display class within the same method
// (closure2.localsX = closure1;)
isDisplayClassParentPointerAssignment = true;
}
}
else if (right is MemberReferenceExpression)
{
// copy of parent display class reference from an outer lambda
// closure2.localsX = this.localsY
MemberReferenceExpression mre = m.Get <MemberReferenceExpression>("right").Single();
do
{
// descend into the targets of the mre as long as the field types are closures
FieldDef fieldDef2 = mre.Annotation <FieldDef>().ResolveFieldWithinSameModule();
if (fieldDef2 == null || !IsPotentialClosure(context, fieldDef2.FieldType.ToTypeDefOrRef().ResolveWithinSameModule()))
{
break;
}
// if we finally get to a this reference, it's copying a display class parent pointer
if (mre.Target is ThisReferenceExpression)
{
isDisplayClassParentPointerAssignment = true;
}
mre = mre.Target as MemberReferenceExpression;
} while (mre != null);
}
if (isParameter || isDisplayClassParentPointerAssignment)
{
if (fieldDef != null)
{
dict[fieldDef] = right;
}
cur.Remove(); //TODO: Save ILRanges
}
else
{
break;
}
}
else
{
break;
}
}
// Now create variables for all fields of the display class (except for those that we already handled as parameters)
List <Tuple <AstType, ILVariable> > variablesToDeclare = new List <Tuple <AstType, ILVariable> >();
foreach (FieldDef field in type.Fields)
{
if (field.IsStatic)
{
continue; // skip static fields
}
if (dict.ContainsKey(field)) // skip field if it already was handled as parameter
{
continue;
}
string capturedVariableName = field.Name;
if (capturedVariableName.StartsWith("$VB$Local_", StringComparison.Ordinal) && capturedVariableName.Length > 10)
{
capturedVariableName = capturedVariableName.Substring(10);
}
EnsureVariableNameIsAvailable(blockStatement, capturedVariableName);
currentlyUsedVariableNames.Add(capturedVariableName);
ILVariable ilVar = new ILVariable
{
IsGenerated = true,
Name = capturedVariableName,
Type = field.FieldType,
};
variablesToDeclare.Add(Tuple.Create(AstBuilder.ConvertType(field.FieldType, field), ilVar));
dict[field] = IdentifierExpression.Create(capturedVariableName, TextTokenType.Local).WithAnnotation(ilVar);
}
// Now figure out where the closure was accessed and use the simpler replacement expression there:
foreach (var identExpr in blockStatement.Descendants.OfType <IdentifierExpression>())
{
if (identExpr.Identifier == variable.Name)
{
MemberReferenceExpression mre = (MemberReferenceExpression)identExpr.Parent;
AstNode replacement;
var fieldDef = mre.Annotation <IField>().ResolveFieldWithinSameModule();
if (fieldDef != null && dict.TryGetValue(fieldDef, out replacement))
{
var newReplacement = replacement.Clone();
newReplacement.AddAnnotation(mre.GetAllRecursiveILRanges());
mre.ReplaceWith(newReplacement);
}
}
}
// Now insert the variable declarations (we can do this after the replacements only so that the scope detection works):
Statement insertionPoint = blockStatement.Statements.FirstOrDefault();
foreach (var tuple in variablesToDeclare)
{
var newVarDecl = new VariableDeclarationStatement(tuple.Item2.IsParameter ? TextTokenType.Parameter : TextTokenType.Local, tuple.Item1, tuple.Item2.Name);
newVarDecl.Variables.Single().AddAnnotation(new CapturedVariableAnnotation());
newVarDecl.Variables.Single().AddAnnotation(tuple.Item2);
blockStatement.Statements.InsertBefore(insertionPoint, newVarDecl);
}
}
currentlyUsedVariableNames.RemoveRange(numberOfVariablesOutsideBlock, currentlyUsedVariableNames.Count - numberOfVariablesOutsideBlock);
return(null);
}
QueryExpression DecompileQuery(InvocationExpression invocation)
{
if (invocation == null)
{
return(null);
}
MemberReferenceExpression mre = invocation.Target as MemberReferenceExpression;
if (mre == null)
{
return(null);
}
switch (mre.MemberName)
{
case "Select":
{
if (invocation.Arguments.Count != 1)
{
return(null);
}
string parameterName;
Expression body;
if (MatchSimpleLambda(invocation.Arguments.Single(), out parameterName, out body))
{
QueryExpression query = new QueryExpression();
query.Clauses.Add(new QueryFromClause {
IdentifierToken = Identifier.Create(parameterName).WithAnnotation(TextTokenKind.Parameter), Expression = mre.Target.Detach()
});
query.Clauses.Add(new QuerySelectClause {
Expression = body.Detach()
});
return(query);
}
return(null);
}
case "GroupBy":
{
if (invocation.Arguments.Count == 2)
{
string parameterName1, parameterName2;
Expression keySelector, elementSelector;
if (MatchSimpleLambda(invocation.Arguments.ElementAt(0), out parameterName1, out keySelector) &&
MatchSimpleLambda(invocation.Arguments.ElementAt(1), out parameterName2, out elementSelector) &&
parameterName1 == parameterName2)
{
QueryExpression query = new QueryExpression();
query.Clauses.Add(new QueryFromClause {
IdentifierToken = Identifier.Create(parameterName1).WithAnnotation(TextTokenKind.Parameter), Expression = mre.Target.Detach()
});
query.Clauses.Add(new QueryGroupClause {
Projection = elementSelector.Detach(), Key = keySelector.Detach()
});
return(query);
}
}
else if (invocation.Arguments.Count == 1)
{
string parameterName;
Expression keySelector;
if (MatchSimpleLambda(invocation.Arguments.Single(), out parameterName, out keySelector))
{
QueryExpression query = new QueryExpression();
query.Clauses.Add(new QueryFromClause {
IdentifierToken = Identifier.Create(parameterName).WithAnnotation(TextTokenKind.Parameter), Expression = mre.Target.Detach()
});
query.Clauses.Add(new QueryGroupClause {
Projection = IdentifierExpression.Create(parameterName, TextTokenKind.Parameter), Key = keySelector.Detach()
});
return(query);
}
}
return(null);
}
case "SelectMany":
{
if (invocation.Arguments.Count != 2)
{
return(null);
}
string parameterName;
Expression collectionSelector;
if (!MatchSimpleLambda(invocation.Arguments.ElementAt(0), out parameterName, out collectionSelector))
{
return(null);
}
LambdaExpression lambda = invocation.Arguments.ElementAt(1) as LambdaExpression;
if (lambda != null && lambda.Parameters.Count == 2 && lambda.Body is Expression)
{
ParameterDeclaration p1 = lambda.Parameters.ElementAt(0);
ParameterDeclaration p2 = lambda.Parameters.ElementAt(1);
if (p1.Name == parameterName)
{
QueryExpression query = new QueryExpression();
query.Clauses.Add(new QueryFromClause {
IdentifierToken = Identifier.Create(p1.Name).WithAnnotation(TextTokenKind.Parameter), Expression = mre.Target.Detach()
});
query.Clauses.Add(new QueryFromClause {
IdentifierToken = Identifier.Create(p2.Name).WithAnnotation(TextTokenKind.Parameter), Expression = collectionSelector.Detach()
});
query.Clauses.Add(new QuerySelectClause {
Expression = ((Expression)lambda.Body).Detach()
});
return(query);
}
}
return(null);
}
case "Where":
{
if (invocation.Arguments.Count != 1)
{
return(null);
}
string parameterName;
Expression body;
if (MatchSimpleLambda(invocation.Arguments.Single(), out parameterName, out body))
{
QueryExpression query = new QueryExpression();
query.Clauses.Add(new QueryFromClause {
IdentifierToken = Identifier.Create(parameterName).WithAnnotation(TextTokenKind.Parameter), Expression = mre.Target.Detach()
});
query.Clauses.Add(new QueryWhereClause {
Condition = body.Detach()
});
return(query);
}
return(null);
}
case "OrderBy":
case "OrderByDescending":
case "ThenBy":
case "ThenByDescending":
{
if (invocation.Arguments.Count != 1)
{
return(null);
}
string parameterName;
Expression orderExpression;
if (MatchSimpleLambda(invocation.Arguments.Single(), out parameterName, out orderExpression))
{
if (ValidateThenByChain(invocation, parameterName))
{
QueryOrderClause orderClause = new QueryOrderClause();
InvocationExpression tmp = invocation;
while (mre.MemberName == "ThenBy" || mre.MemberName == "ThenByDescending")
{
// insert new ordering at beginning
orderClause.Orderings.InsertAfter(
null, new QueryOrdering {
Expression = orderExpression.Detach(),
Direction = (mre.MemberName == "ThenBy" ? QueryOrderingDirection.None : QueryOrderingDirection.Descending)
});
tmp = (InvocationExpression)mre.Target;
mre = (MemberReferenceExpression)tmp.Target;
MatchSimpleLambda(tmp.Arguments.Single(), out parameterName, out orderExpression);
}
// insert new ordering at beginning
orderClause.Orderings.InsertAfter(
null, new QueryOrdering {
Expression = orderExpression.Detach(),
Direction = (mre.MemberName == "OrderBy" ? QueryOrderingDirection.None : QueryOrderingDirection.Descending)
});
QueryExpression query = new QueryExpression();
query.Clauses.Add(new QueryFromClause {
IdentifierToken = Identifier.Create(parameterName).WithAnnotation(TextTokenKind.Parameter), Expression = mre.Target.Detach()
});
query.Clauses.Add(orderClause);
return(query);
}
}
return(null);
}
case "Join":
case "GroupJoin":
{
if (invocation.Arguments.Count != 4)
{
return(null);
}
Expression source1 = mre.Target;
Expression source2 = invocation.Arguments.ElementAt(0);
string elementName1, elementName2;
Expression key1, key2;
if (!MatchSimpleLambda(invocation.Arguments.ElementAt(1), out elementName1, out key1))
{
return(null);
}
if (!MatchSimpleLambda(invocation.Arguments.ElementAt(2), out elementName2, out key2))
{
return(null);
}
LambdaExpression lambda = invocation.Arguments.ElementAt(3) as LambdaExpression;
if (lambda != null && lambda.Parameters.Count == 2 && lambda.Body is Expression)
{
ParameterDeclaration p1 = lambda.Parameters.ElementAt(0);
ParameterDeclaration p2 = lambda.Parameters.ElementAt(1);
if (p1.Name == elementName1 && (p2.Name == elementName2 || mre.MemberName == "GroupJoin"))
{
QueryExpression query = new QueryExpression();
query.Clauses.Add(new QueryFromClause {
IdentifierToken = Identifier.Create(elementName1).WithAnnotation(TextTokenKind.Parameter), Expression = source1.Detach()
});
QueryJoinClause joinClause = new QueryJoinClause();
joinClause.JoinIdentifierToken = Identifier.Create(elementName2).WithAnnotation(TextTokenKind.Parameter); // join elementName2
joinClause.InExpression = source2.Detach(); // in source2
joinClause.OnExpression = key1.Detach(); // on key1
joinClause.EqualsExpression = key2.Detach(); // equals key2
if (mre.MemberName == "GroupJoin")
{
joinClause.IntoIdentifierToken = Identifier.Create(p2.Name).WithAnnotation(TextTokenKind.Parameter); // into p2.Name
}
query.Clauses.Add(joinClause);
query.Clauses.Add(new QuerySelectClause {
Expression = ((Expression)lambda.Body).Detach()
});
return(query);
}
}
return(null);
}
default:
return(null);
}
}