public ExtractMethodModel(IActiveCodePaneEditor editor, Declarations declarations, QualifiedSelection selection)
{
_sourceMember = declarations.FindSelectedDeclaration(selection, Declarations.ProcedureTypes, d => ((ParserRuleContext)d.Context.Parent).GetSelection());
if (_sourceMember == null)
{
throw new InvalidOperationException("Invalid selection.");
}
_extractedMethod = new ExtractedMethod();
_selection = selection;
_selectedCode = editor.GetLines(selection.Selection);
var inScopeDeclarations = declarations.Items.Where(item => item.ParentScope == _sourceMember.Scope).ToList();
var inSelection = inScopeDeclarations.SelectMany(item => item.References)
.Where(item => selection.Selection.Contains(item.Selection))
.ToList();
var usedInSelection = new HashSet <Declaration>(inScopeDeclarations.Where(item =>
item.References.Any(reference => inSelection.Contains(reference))));
var usedBeforeSelection = new HashSet <Declaration>(inScopeDeclarations.Where(item =>
item.References.Any(reference => reference.Selection.StartLine < selection.Selection.StartLine)));
var usedAfterSelection = new HashSet <Declaration>(inScopeDeclarations.Where(item =>
item.References.Any(reference => reference.Selection.StartLine > selection.Selection.EndLine)));
// identifiers used inside selection and before selection (or if it's a parameter) are candidates for parameters:
var input = inScopeDeclarations.Where(item =>
usedInSelection.Contains(item) && (usedBeforeSelection.Contains(item) || item.DeclarationType == DeclarationType.Parameter)).ToList();
// identifiers used inside selection and after selection are candidates for return values:
var output = inScopeDeclarations.Where(item =>
usedInSelection.Contains(item) && usedAfterSelection.Contains(item))
.ToList();
// identifiers used only inside and/or after selection are candidates for locals:
_locals = inScopeDeclarations.Where(item => item.DeclarationType != DeclarationType.Parameter && (
item.References.All(reference => inSelection.Contains(reference)) ||
(usedAfterSelection.Contains(item) && (!usedBeforeSelection.Contains(item)))))
.ToList();
// locals that are only used in selection are candidates for being moved into the new method:
_declarationsToMove = _locals.Where(item => !usedAfterSelection.Contains(item)).ToList();
_output = output.Select(declaration =>
new ExtractedParameter(declaration.AsTypeName, ExtractedParameter.PassedBy.ByRef, declaration.IdentifierName));
_input = input.Where(declaration => !output.Contains(declaration))
.Select(declaration =>
new ExtractedParameter(declaration.AsTypeName, ExtractedParameter.PassedBy.ByVal, declaration.IdentifierName));
}
