public static List <IVariable> Analyze(RefactoringContext context, List <AstNode> statements)
{
var visitor = new VariableLookupVisitor(context);
statements.ForEach(stmt => stmt.AcceptVisitor(visitor));
return(visitor.UsedVariables);
}
public static List <IVariable> Analyze(RefactoringContext context, Expression expression)
{
var visitor = new VariableLookupVisitor(context);
expression.AcceptVisitor(visitor);
return(visitor.UsedVariables);
}
static bool ContainsLocalReferences(RefactoringContext context, AstNode expr, AstNode body)
{
var visitor = new ExtractMethod.VariableLookupVisitor(context);
body.AcceptVisitor(visitor);
return(visitor.UsedVariables.Any(variable => !expr.Contains(variable.Region.Begin)));
}
CodeAction CreateFromExpression(RefactoringContext context, Expression expression)
{
var resolveResult = context.Resolve(expression);
if (resolveResult.IsError)
{
return(null);
}
return(new CodeAction(context.TranslateString("Extract method"), script => {
string methodName = "NewMethod";
var method = new MethodDeclaration {
ReturnType = context.CreateShortType(resolveResult.Type),
Name = methodName,
Body = new BlockStatement {
new ReturnStatement(expression.Clone())
}
};
if (!StaticVisitor.UsesNotStaticMember(context, expression))
{
method.Modifiers |= Modifiers.Static;
}
var usedVariables = VariableLookupVisitor.Analyze(context, expression);
var inExtractedRegion = new VariableUsageAnalyzation(context, usedVariables);
usedVariables.Sort((l, r) => l.Region.Begin.CompareTo(r.Region.Begin));
var target = new IdentifierExpression(methodName);
var invocation = new InvocationExpression(target);
foreach (var variable in usedVariables)
{
Expression argumentExpression = new IdentifierExpression(variable.Name);
var mod = ParameterModifier.None;
if (inExtractedRegion.GetStatus(variable) == VariableState.Changed)
{
mod = ParameterModifier.Ref;
argumentExpression = new DirectionExpression(FieldDirection.Ref, argumentExpression);
}
method.Parameters.Add(new ParameterDeclaration(context.CreateShortType(variable.Type), variable.Name, mod));
invocation.Arguments.Add(argumentExpression);
}
script
.InsertWithCursor(context.TranslateString("Extract method"), Script.InsertPosition.Before, method)
.ContinueScript(delegate {
script.Replace(expression, invocation);
script.Link(target, method.NameToken);
});
}, expression));
}
CodeAction CreateFromStatements(RefactoringContext context, List <AstNode> 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("sub"),
Name = methodName,
Body = new BlockStatement()
};
bool usesNonStaticMember = false;
foreach (var node in statements)
{
usesNonStaticMember |= StaticVisitor.UsesNotStaticMember(context, node);
if (node is Statement)
{
method.Body.Add((Statement)node.Clone());
}
else
{
method.Body.AddChildUnsafe(node.Clone(), node.Role);
}
}
if (!usesNonStaticMember)
{
method.Modifiers |= Modifiers.Static;
}
var target = new IdentifierExpression(methodName);
var invocation = new InvocationExpression(target);
var usedVariables = VariableLookupVisitor.Analyze(context, statements);
var inExtractedRegion = new VariableUsageAnalyzation(context, usedVariables);
var lastStatement = statements [statements.Count - 1];
var stmt = statements [0].GetParent <BlockStatement>();
while (stmt.GetParent <BlockStatement> () != null)
{
stmt = stmt.GetParent <BlockStatement>();
}
inExtractedRegion.SetAnalyzedRange(statements [0], lastStatement);
stmt.AcceptVisitor(inExtractedRegion);
var beforeExtractedRegion = new VariableUsageAnalyzation(context, usedVariables);
beforeExtractedRegion.SetAnalyzedRange(statements [0].Parent, statements [0], true, false);
stmt.AcceptVisitor(beforeExtractedRegion);
var afterExtractedRegion = new VariableUsageAnalyzation(context, usedVariables);
afterExtractedRegion.SetAnalyzedRange(lastStatement, stmt.Statements.Last(), false, true);
stmt.AcceptVisitor(afterExtractedRegion);
usedVariables.Sort((l, r) => l.Region.Begin.CompareTo(r.Region.Begin));
IVariable generatedReturnVariable = null;
foreach (var variable in usedVariables)
{
if ((variable is IParameter) || beforeExtractedRegion.Has(variable) || !afterExtractedRegion.Has(variable))
{
continue;
}
generatedReturnVariable = variable;
method.ReturnType = context.CreateShortType(variable.Type);
method.Body.Add(new ReturnStatement(new IdentifierExpression(variable.Name)));
break;
}
int parameterOutCount = 0;
foreach (var variable in usedVariables)
{
if (!(variable is IParameter) && !beforeExtractedRegion.Has(variable) && !afterExtractedRegion.Has(variable))
{
continue;
}
if (variable == generatedReturnVariable)
{
continue;
}
Expression argumentExpression = new IdentifierExpression(variable.Name);
ParameterModifier mod = ParameterModifier.None;
if (inExtractedRegion.GetStatus(variable) == VariableState.Changed)
{
if (beforeExtractedRegion.GetStatus(variable) == VariableState.None)
{
mod = ParameterModifier.Out;
argumentExpression = new DirectionExpression(FieldDirection.Out, argumentExpression);
parameterOutCount++;
}
else
{
mod = ParameterModifier.Ref;
argumentExpression = new DirectionExpression(FieldDirection.Ref, argumentExpression);
}
}
method.Parameters.Add(new ParameterDeclaration(context.CreateShortType(variable.Type), variable.Name, mod));
invocation.Arguments.Add(argumentExpression);
}
ParameterDeclaration parameterToTransform = null;
bool transformParameterToReturn = method.ReturnType is PrimitiveType &&
((PrimitiveType)method.ReturnType).Keyword == "sub" &&
parameterOutCount == 1;
if (transformParameterToReturn)
{
parameterToTransform = method.Parameters.First(p => p.ParameterModifier == ParameterModifier.Out);
parameterToTransform.Remove();
var argumentExpression = invocation.Arguments.OfType <DirectionExpression>().First(a => a.FieldDirection == FieldDirection.Out);
argumentExpression.Remove();
method.ReturnType = parameterToTransform.Type.Clone();
var argumentDecl = new VariableDeclarationStatement(parameterToTransform.Type.Clone(), parameterToTransform.Name);
method.Body.InsertChildBefore(method.Body.First(), argumentDecl, BlockStatement.StatementRole);
method.Body.Add(new ReturnStatement(new IdentifierExpression(parameterToTransform.Name)));
}
script
.InsertWithCursor(context.TranslateString("Extract method"), Script.InsertPosition.Before, method)
.ContinueScript(delegate {
foreach (var node in statements.Skip(1))
{
if (node is NewLineNode)
{
continue;
}
script.Remove(node);
}
foreach (var variable in usedVariables)
{
if ((variable is IParameter) || beforeExtractedRegion.Has(variable) || !afterExtractedRegion.Has(variable))
{
continue;
}
if (variable == generatedReturnVariable)
{
continue;
}
script.InsertBefore(statements [0], new VariableDeclarationStatement(context.CreateShortType(variable.Type), variable.Name));
}
Statement invocationStatement;
if (generatedReturnVariable != null)
{
invocationStatement = new VariableDeclarationStatement(new SimpleType("var"), generatedReturnVariable.Name, invocation);
}
else if (transformParameterToReturn)
{
invocationStatement = new AssignmentExpression(new IdentifierExpression(parameterToTransform.Name), invocation);
}
else
{
invocationStatement = invocation;
}
script.Replace(statements [0], invocationStatement);
script.Link(target, method.NameToken);
});
}, statements.First().StartLocation, statements.Last().EndLocation));
}