public void TryFinally()
{
BlockStatement block = new BlockStatement {
new TryCatchStatement {
TryBlock = new BlockStatement {
new GotoStatement("LABEL"),
new AssignmentExpression(new IdentifierExpression("i"), new PrimitiveExpression(1))
},
CatchClauses = {
new CatchClause {
Body = new BlockStatement {
new AssignmentExpression(new IdentifierExpression("i"), new PrimitiveExpression(3))
}
}
},
FinallyBlock = new BlockStatement {
new AssignmentExpression(new IdentifierExpression("j"), new PrimitiveExpression(5))
}
},
new LabelStatement { Label = "LABEL" },
new EmptyStatement()
};
TryCatchStatement tryCatchStatement = (TryCatchStatement)block.Statements.First();
Statement stmt1 = tryCatchStatement.TryBlock.Statements.ElementAt(1);
Statement stmt3 = tryCatchStatement.CatchClauses.Single().Body.Statements.Single();
Statement stmt5 = tryCatchStatement.FinallyBlock.Statements.Single();
LabelStatement label = (LabelStatement)block.Statements.ElementAt(1);
DefiniteAssignmentAnalysis da = new DefiniteAssignmentAnalysis(block, CecilLoaderTests.Mscorlib);
da.Analyze("i");
Assert.AreEqual(0, da.UnassignedVariableUses.Count);
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(tryCatchStatement));
Assert.AreEqual(DefiniteAssignmentStatus.CodeUnreachable, da.GetStatusBefore(stmt1));
Assert.AreEqual(DefiniteAssignmentStatus.CodeUnreachable, da.GetStatusAfter(stmt1));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(stmt3));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(stmt3));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(stmt5));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusAfter(stmt5));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(tryCatchStatement));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusBefore(label));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusAfter(label));
da.Analyze("j");
Assert.AreEqual(0, da.UnassignedVariableUses.Count);
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(tryCatchStatement));
Assert.AreEqual(DefiniteAssignmentStatus.CodeUnreachable, da.GetStatusBefore(stmt1));
Assert.AreEqual(DefiniteAssignmentStatus.CodeUnreachable, da.GetStatusAfter(stmt1));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(stmt3));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusAfter(stmt3));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(stmt5));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(stmt5));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(tryCatchStatement));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusBefore(label));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(label));
}
static bool FindDeclarationPoint(DefiniteAssignmentAnalysis daa, string variableName, bool allowPassIntoLoops, BlockStatement block, out Statement declarationPoint)
{
// declarationPoint: The point where the variable would be declared, if we decide to declare it in this block
declarationPoint = null;
foreach (Statement stmt in block.Statements)
{
if (UsesVariable(stmt, variableName))
{
if (declarationPoint == null)
{
declarationPoint = stmt;
}
if (!CanMoveVariableUseIntoSubBlock(stmt, variableName, allowPassIntoLoops))
{
// If it's not possible to move the variable use into a nested block,
// we need to declare the variable in this block
return(false);
}
// If we can move the variable into the sub-block, we need to ensure that the remaining code
// does not use the value that was assigned by the first sub-block
Statement nextStatement = stmt.GetNextStatement();
if (nextStatement != null)
{
// Analyze the range from the next statement to the end of the block
daa.SetAnalyzedRange(nextStatement, block);
daa.Analyze(variableName);
if (daa.UnassignedVariableUses.Count > 0)
{
return(false);
}
}
}
}
return(true);
}
static bool FindDeclarationPoint(DefiniteAssignmentAnalysis daa, string variableName, bool allowPassIntoLoops, BlockStatement block, out Statement declarationPoint)
{
// declarationPoint: The point where the variable would be declared, if we decide to declare it in this block
declarationPoint = null;
foreach (Statement stmt in block.Statements) {
if (UsesVariable(stmt, variableName)) {
if (declarationPoint == null)
declarationPoint = stmt;
if (!CanMoveVariableUseIntoSubBlock(stmt, variableName, allowPassIntoLoops)) {
// If it's not possible to move the variable use into a nested block,
// we need to declare the variable in this block
return false;
}
// If we can move the variable into the sub-block, we need to ensure that the remaining code
// does not use the value that was assigned by the first sub-block
Statement nextStatement = stmt.GetNextStatement();
if (nextStatement != null) {
// Analyze the range from the next statement to the end of the block
daa.SetAnalyzedRange(nextStatement, block);
daa.Analyze(variableName);
if (daa.UnassignedVariableUses.Count > 0) {
return false;
}
}
}
}
return true;
}
CodeAction CreateFromStatements(RefactoringContext context, List<Statement> statements)
{
if (!(statements [0].Parent is Statement))
return null;
return new CodeAction(context.TranslateString("Extract method"), script => {
string methodName = "NewMethod";
var method = new MethodDeclaration() {
ReturnType = new PrimitiveType("void"),
Name = methodName,
Body = new BlockStatement()
};
bool usesNonStaticMember = false;
foreach (Statement node in statements) {
usesNonStaticMember |= StaticVisitor.UsesNotStaticMember(context, node);
method.Body.Add(node.Clone());
}
if (!usesNonStaticMember)
method.Modifiers |= Modifiers.Static;
var target = new IdentifierExpression(methodName);
var invocation = new InvocationExpression(target);
var usedVariables = VariableLookupVisitor.Analyze(context, statements);
var extractedCodeAnalysis = new DefiniteAssignmentAnalysis(
(Statement)statements [0].Parent,
context.Resolver,
context.CancellationToken);
var lastStatement = statements [statements.Count - 1];
extractedCodeAnalysis.SetAnalyzedRange(statements [0], lastStatement);
var statusAfterMethod = new List<Tuple<IVariable, DefiniteAssignmentStatus>>();
foreach (var variable in usedVariables) {
extractedCodeAnalysis.Analyze(
variable.Name,
DefiniteAssignmentStatus.PotentiallyAssigned,
context.CancellationToken);
statusAfterMethod.Add(Tuple.Create(variable, extractedCodeAnalysis.GetStatusAfter(lastStatement)));
}
var stmt = statements [0].GetParent<BlockStatement>();
while (stmt.GetParent<BlockStatement> () != null) {
stmt = stmt.GetParent<BlockStatement>();
}
var wholeCodeAnalysis = new DefiniteAssignmentAnalysis(stmt, context.Resolver, context.CancellationToken);
var statusBeforeMethod = new Dictionary<IVariable, DefiniteAssignmentStatus>();
foreach (var variable in usedVariables) {
wholeCodeAnalysis.Analyze(variable.Name, DefiniteAssignmentStatus.PotentiallyAssigned, context.CancellationToken);
statusBeforeMethod [variable] = extractedCodeAnalysis.GetStatusBefore(statements [0]);
}
var afterCodeAnalysis = new DefiniteAssignmentAnalysis(stmt, context.Resolver, context.CancellationToken);
var statusAtEnd = new Dictionary<IVariable, DefiniteAssignmentStatus>();
afterCodeAnalysis.SetAnalyzedRange(lastStatement, stmt.Statements.Last(), false, true);
foreach (var variable in usedVariables) {
afterCodeAnalysis.Analyze(variable.Name, DefiniteAssignmentStatus.PotentiallyAssigned, context.CancellationToken);
statusBeforeMethod [variable] = extractedCodeAnalysis.GetStatusBefore(statements [0]);
}
var beforeVisitor = new VariableLookupVisitor(context);
beforeVisitor.SetAnalyzedRange(stmt, statements [0], true, false);
stmt.AcceptVisitor(beforeVisitor);
var afterVisitor = new VariableLookupVisitor(context);
afterVisitor.SetAnalyzedRange(lastStatement, stmt, false, true);
stmt.AcceptVisitor(afterVisitor);
foreach (var status in statusAfterMethod) {
if (!beforeVisitor.UsedVariables.Contains(status.Item1) && !afterVisitor.UsedVariables.Contains(status.Item1))
continue;
Expression argumentExpression = new IdentifierExpression(status.Item1.Name);
ParameterModifier mod;
switch (status.Item2) {
case DefiniteAssignmentStatus.AssignedAfterTrueExpression:
case DefiniteAssignmentStatus.AssignedAfterFalseExpression:
case DefiniteAssignmentStatus.PotentiallyAssigned:
mod = ParameterModifier.Ref;
argumentExpression = new DirectionExpression(FieldDirection.Ref, argumentExpression);
break;
case DefiniteAssignmentStatus.DefinitelyAssigned:
if (statusBeforeMethod [status.Item1] != DefiniteAssignmentStatus.PotentiallyAssigned)
goto case DefiniteAssignmentStatus.PotentiallyAssigned;
mod = ParameterModifier.Out;
argumentExpression = new DirectionExpression(FieldDirection.Out, argumentExpression);
break;
// case DefiniteAssignmentStatus.Unassigned:
default:
mod = ParameterModifier.None;
break;
}
method.Parameters.Add(
new ParameterDeclaration(context.CreateShortType(status.Item1.Type), status.Item1.Name, mod));
invocation.Arguments.Add(argumentExpression);
}
var task = script.InsertWithCursor(context.TranslateString("Extract method"), Script.InsertPosition.Before, method);
task.ContinueWith (delegate {
foreach (var node in statements.Skip (1)) {
script.Remove(node);
}
script.Replace(statements [0], new ExpressionStatement(invocation));
script.Link(target, method.NameToken);
}, TaskScheduler.FromCurrentSynchronizationContext ());
});
}
CodeAction CreateFromStatements(RefactoringContext context, List <Statement> statements)
{
if (!(statements [0].Parent is Statement))
{
return(null);
}
return(new CodeAction(context.TranslateString("Extract method"), script => {
string methodName = "NewMethod";
var method = new MethodDeclaration()
{
ReturnType = new PrimitiveType("void"),
Name = methodName,
Body = new BlockStatement()
};
bool usesNonStaticMember = false;
foreach (Statement node in statements)
{
usesNonStaticMember |= StaticVisitor.UsesNotStaticMember(context, node);
method.Body.Add(node.Clone());
}
if (!usesNonStaticMember)
{
method.Modifiers |= Modifiers.Static;
}
var target = new IdentifierExpression(methodName);
var invocation = new InvocationExpression(target);
var usedVariables = VariableLookupVisitor.Analyze(context, statements);
var extractedCodeAnalysis = new DefiniteAssignmentAnalysis((Statement)statements [0].Parent, context.Resolver, context.CancellationToken);
var lastStatement = statements [statements.Count - 1];
extractedCodeAnalysis.SetAnalyzedRange(statements [0], lastStatement);
var statusAfterMethod = new List <Tuple <IVariable, DefiniteAssignmentStatus> >();
foreach (var variable in usedVariables)
{
extractedCodeAnalysis.Analyze(variable.Name, DefiniteAssignmentStatus.PotentiallyAssigned, context.CancellationToken);
statusAfterMethod.Add(Tuple.Create(variable, extractedCodeAnalysis.GetStatusAfter(lastStatement)));
}
var stmt = statements [0].GetParent <BlockStatement>();
while (stmt.GetParent <BlockStatement> () != null)
{
stmt = stmt.GetParent <BlockStatement>();
}
var wholeCodeAnalysis = new DefiniteAssignmentAnalysis(stmt, context.Resolver, context.CancellationToken);
var statusBeforeMethod = new Dictionary <IVariable, DefiniteAssignmentStatus>();
foreach (var variable in usedVariables)
{
wholeCodeAnalysis.Analyze(variable.Name, DefiniteAssignmentStatus.PotentiallyAssigned, context.CancellationToken);
statusBeforeMethod [variable] = extractedCodeAnalysis.GetStatusBefore(statements [0]);
}
var afterCodeAnalysis = new DefiniteAssignmentAnalysis(stmt, context.Resolver, context.CancellationToken);
var statusAtEnd = new Dictionary <IVariable, DefiniteAssignmentStatus>();
afterCodeAnalysis.SetAnalyzedRange(lastStatement, stmt.Statements.Last(), false, true);
foreach (var variable in usedVariables)
{
afterCodeAnalysis.Analyze(variable.Name, DefiniteAssignmentStatus.PotentiallyAssigned, context.CancellationToken);
statusBeforeMethod [variable] = extractedCodeAnalysis.GetStatusBefore(statements [0]);
}
var beforeVisitor = new VariableLookupVisitor(context);
beforeVisitor.SetAnalyzedRange(stmt, statements [0], true, false);
stmt.AcceptVisitor(beforeVisitor);
var afterVisitor = new VariableLookupVisitor(context);
afterVisitor.SetAnalyzedRange(lastStatement, stmt, false, true);
stmt.AcceptVisitor(afterVisitor);
foreach (var status in statusAfterMethod)
{
if (!beforeVisitor.UsedVariables.Contains(status.Item1) && !afterVisitor.UsedVariables.Contains(status.Item1))
{
continue;
}
Expression argumentExpression = new IdentifierExpression(status.Item1.Name);
ParameterModifier mod;
switch (status.Item2)
{
case DefiniteAssignmentStatus.AssignedAfterTrueExpression:
case DefiniteAssignmentStatus.AssignedAfterFalseExpression:
case DefiniteAssignmentStatus.PotentiallyAssigned:
mod = ParameterModifier.Ref;
argumentExpression = new DirectionExpression(FieldDirection.Ref, argumentExpression);
break;
case DefiniteAssignmentStatus.DefinitelyAssigned:
if (statusBeforeMethod [status.Item1] != DefiniteAssignmentStatus.PotentiallyAssigned)
{
goto case DefiniteAssignmentStatus.PotentiallyAssigned;
}
mod = ParameterModifier.Out;
argumentExpression = new DirectionExpression(FieldDirection.Out, argumentExpression);
break;
// case DefiniteAssignmentStatus.Unassigned:
default:
mod = ParameterModifier.None;
break;
}
method.Parameters.Add(new ParameterDeclaration(context.CreateShortType(status.Item1.Type), status.Item1.Name, mod));
invocation.Arguments.Add(argumentExpression);
}
foreach (var node in statements.Skip(1))
{
script.Remove(node);
}
script.Replace(statements [0], new ExpressionStatement(invocation));
script.InsertWithCursor(context.TranslateString("Extract method"), method, Script.InsertPosition.Before);
//script.Link(target, method.NameToken);
}));
}
public void ConditionalAnd()
{
IfElseStatement ifStmt = new IfElseStatement {
Condition = new BinaryOperatorExpression {
Left = new BinaryOperatorExpression(new IdentifierExpression("x"), BinaryOperatorType.GreaterThan, new PrimitiveExpression(0)),
Operator = BinaryOperatorType.ConditionalAnd,
Right = new BinaryOperatorExpression {
Left = new ParenthesizedExpression {
Expression = new AssignmentExpression {
Left = new IdentifierExpression("i"),
Operator = AssignmentOperatorType.Assign,
Right = new IdentifierExpression("y")
}
},
Operator = BinaryOperatorType.GreaterThanOrEqual,
Right = new PrimitiveExpression(0)
}
},
TrueStatement = new BlockStatement(),
FalseStatement = new BlockStatement()
};
DefiniteAssignmentAnalysis da = new DefiniteAssignmentAnalysis(ifStmt, CecilLoaderTests.Mscorlib);
da.Analyze("i");
Assert.AreEqual(0, da.UnassignedVariableUses.Count);
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(ifStmt));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusBefore(ifStmt.TrueStatement));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(ifStmt.FalseStatement));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusAfter(ifStmt));
}
public void ForLoop()
{
ForStatement loop = new ForStatement {
Initializers = {
new ExpressionStatement(
new AssignmentExpression(new IdentifierExpression("i"), new PrimitiveExpression(0))
)
},
Condition = new BinaryOperatorExpression(new IdentifierExpression("i"), BinaryOperatorType.LessThan, new PrimitiveExpression(1000)),
Iterators = {
new ExpressionStatement(
new AssignmentExpression {
Left = new IdentifierExpression("i"),
Operator = AssignmentOperatorType.Add,
Right = new IdentifierExpression("j")
}
)
},
EmbeddedStatement = new ExpressionStatement(
new AssignmentExpression(new IdentifierExpression("j"), new IdentifierExpression("i"))
)};
DefiniteAssignmentAnalysis da = new DefiniteAssignmentAnalysis(loop, CecilLoaderTests.Mscorlib);
da.Analyze("i");
Assert.AreEqual(0, da.UnassignedVariableUses.Count);
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(loop));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(loop.Initializers.Single()));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(loop.Initializers.Single()));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusBeforeLoopCondition(loop));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusBefore(loop.EmbeddedStatement));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(loop.EmbeddedStatement));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusBefore(loop.Iterators.Single()));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(loop.Iterators.Single()));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(loop));
da.Analyze("j");
Assert.AreEqual(0, da.UnassignedVariableUses.Count);
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(loop));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(loop.Initializers.Single()));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusAfter(loop.Initializers.Single()));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBeforeLoopCondition(loop));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(loop.EmbeddedStatement));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(loop.EmbeddedStatement));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusBefore(loop.Iterators.Single()));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(loop.Iterators.Single()));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusAfter(loop));
}
public void WhileTrue()
{
WhileStatement loop = new WhileStatement {
Condition = new PrimitiveExpression(true),
EmbeddedStatement = new BlockStatement {
new AssignmentExpression(new IdentifierExpression("i"), new PrimitiveExpression(0)),
new BreakStatement()
}
};
DefiniteAssignmentAnalysis da = new DefiniteAssignmentAnalysis(loop, CecilLoaderTests.Mscorlib);
da.Analyze("i");
Assert.AreEqual(0, da.UnassignedVariableUses.Count);
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(loop));
Assert.AreEqual(DefiniteAssignmentStatus.PotentiallyAssigned, da.GetStatusBefore(loop.EmbeddedStatement));
Assert.AreEqual(DefiniteAssignmentStatus.CodeUnreachable, da.GetStatusAfter(loop.EmbeddedStatement));
Assert.AreEqual(DefiniteAssignmentStatus.DefinitelyAssigned, da.GetStatusAfter(loop));
}