[Source Tooling] Refactoring action to convert to computed property

include/swift/IDE/RefactoringKinds.def

@@ -70,6 +70,8 @@ RANGE_REFACTORING(ConvertIfLetExprToGuardExpr, "Convert To Guard Expression", co
 
 RANGE_REFACTORING(ConvertGuardExprToIfLetExpr, "Convert To IfLet Expression", convert.to.iflet.expr)
 
+RANGE_REFACTORING(ConvertToComputedProperty, "Convert To Computed Property", convert.to.computed.property)
+
 // These internal refactorings are designed to be helpful for working on
 // the compiler/standard library, etc., but are likely to be just confusing and
 // noise for general development.

lib/IDE/Refactoring.cpp

@@ -3166,6 +3166,97 @@ static bool rangeStartMayNeedRename(ResolvedRangeInfo Info) {
   }
   llvm_unreachable("unhandled kind");
 }
+
+bool RefactoringActionConvertToComputedProperty::
+isApplicable(ResolvedRangeInfo Info, DiagnosticEngine &Diag) {
+  if (Info.Kind != RangeKind::SingleDecl) {
+    return false;
+  }
+
+  if (Info.ContainedNodes.size() != 1) {
+    return false;
+  }
+
+  auto D = Info.ContainedNodes[0].dyn_cast<Decl*>();
+  if (!D) {
+    return false;
+  }
+
+  auto Binding = dyn_cast<PatternBindingDecl>(D);
+  if (!Binding) {
+    return false;
+  }
+
+  auto SV = Binding->getSingleVar();
+  if (!SV) {
+    return false;
+  }
+
+  // willSet, didSet cannot be provided together with a getter
+  for (auto AD : SV->getAllAccessors()) {
+    if (AD->isObservingAccessor()) {
+      return false;
+    }
+  }
+
+  // 'lazy' must not be used on a computed property
+  // NSCopying and IBOutlet attribute requires property to be mutable
+  auto Attributies = SV->getAttrs();
+  if (Attributies.hasAttribute<LazyAttr>() ||
+      Attributies.hasAttribute<NSCopyingAttr>() ||
+      Attributies.hasAttribute<IBOutletAttr>()) {
+    return false;
+  }
+
+  // Property wrapper cannot be applied to a computed property
+  if (SV->hasAttachedPropertyWrapper()) {
+    return false;
+  }
+
+  // has an initializer
+  return Binding->hasInitStringRepresentation(0);
+}
+
+bool RefactoringActionConvertToComputedProperty::performChange() {
+  // Get an initialization
+  auto D = RangeInfo.ContainedNodes[0].dyn_cast<Decl*>();
+  auto Binding = dyn_cast<PatternBindingDecl>(D);
+  SmallString<128> scratch;
+  auto Init = Binding->getInitStringRepresentation(0, scratch);
+
+  // Get type
+  auto SV = Binding->getSingleVar();
+  auto SVType = SV->getType();
+  auto TR = SV->getTypeReprOrParentPatternTypeRepr();
+
+  llvm::SmallString<64> DeclBuffer;
+  llvm::raw_svector_ostream OS(DeclBuffer);
+  llvm::StringRef Space = " ";
+  llvm::StringRef NewLine = "\n";
+
+  OS << tok::kw_var << Space;
+  // Add var name
+  OS << SV->getNameStr().str() << ":" << Space;
+  // For computed property must write a type of var
+  if (TR) {
+    OS << Lexer::getCharSourceRangeFromSourceRange(SM, TR->getSourceRange()).str();
+  } else {
+    SVType.print(OS);
+  }
+
+  OS << Space << tok::l_brace << NewLine;
+  // Add an initialization
+  OS << tok::kw_return << Space << Init.str() << NewLine;
+  OS << tok::r_brace;
+
+  // Replace initializer to computed property
+  auto ReplaceStartLoc = Binding->getLoc();
+  auto ReplaceEndLoc = Binding->getSourceRange().End;
+  auto ReplaceRange = SourceRange(ReplaceStartLoc, ReplaceEndLoc);
+  auto ReplaceCharSourceRange = Lexer::getCharSourceRangeFromSourceRange(SM, ReplaceRange);
+  EditConsumer.accept(SM, ReplaceCharSourceRange, DeclBuffer.str());
+  return false; // success
+}
 }// end of anonymous namespace
 
 StringRef swift::ide::

test/refactoring/ConvertToComputedProperty/Outputs/basic/L10-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1 = 2
+  var field2 = "2"
+  var field3 = String()
+  static var field4 = 4
+  var y: Int! = 45
+}
+
+class C {
+  static var field1: S {
+return S()
+}
+  public var field2 = 2
+  private dynamic var field3 = 5
+  @available(macOS 10.12, *) private static dynamic var field4 = 4
+  let field5 = 5
+}
+
+
+
+
+
+
+
+
+
+
+

test/refactoring/ConvertToComputedProperty/Outputs/basic/L11-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1 = 2
+  var field2 = "2"
+  var field3 = String()
+  static var field4 = 4
+  var y: Int! = 45
+}
+
+class C {
+  static var field1 = S()
+  public var field2: Int {
+return 2
+}
+  private dynamic var field3 = 5
+  @available(macOS 10.12, *) private static dynamic var field4 = 4
+  let field5 = 5
+}
+
+
+
+
+
+
+
+
+
+
+

test/refactoring/ConvertToComputedProperty/Outputs/basic/L12-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1 = 2
+  var field2 = "2"
+  var field3 = String()
+  static var field4 = 4
+  var y: Int! = 45
+}
+
+class C {
+  static var field1 = S()
+  public var field2 = 2
+  private dynamic var field3: Int {
+return 5
+}
+  @available(macOS 10.12, *) private static dynamic var field4 = 4
+  let field5 = 5
+}
+
+
+
+
+
+
+
+
+
+
+

test/refactoring/ConvertToComputedProperty/Outputs/basic/L13-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1 = 2
+  var field2 = "2"
+  var field3 = String()
+  static var field4 = 4
+  var y: Int! = 45
+}
+
+class C {
+  static var field1 = S()
+  public var field2 = 2
+  private dynamic var field3 = 5
+  @available(macOS 10.12, *) private static dynamic var field4: Int {
+return 4
+}
+  let field5 = 5
+}
+
+
+
+
+
+
+
+
+
+
+

test/refactoring/ConvertToComputedProperty/Outputs/basic/L14-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1 = 2
+  var field2 = "2"
+  var field3 = String()
+  static var field4 = 4
+  var y: Int! = 45
+}
+
+class C {
+  static var field1 = S()
+  public var field2 = 2
+  private dynamic var field3 = 5
+  @available(macOS 10.12, *) private static dynamic var field4 = 4
+  var field5: Int {
+return 5
+}
+}
+
+
+
+
+
+
+
+
+
+
+

test/refactoring/ConvertToComputedProperty/Outputs/basic/L2-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1: Int {
+return 2
+}
+  var field2 = "2"
+  var field3 = String()
+  static var field4 = 4
+  var y: Int! = 45
+}
+
+class C {
+  static var field1 = S()
+  public var field2 = 2
+  private dynamic var field3 = 5
+  @available(macOS 10.12, *) private static dynamic var field4 = 4
+  let field5 = 5
+}
+
+
+
+
+
+
+
+
+
+
+

test/refactoring/ConvertToComputedProperty/Outputs/basic/L3-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1 = 2
+  var field2: String {
+return "2"
+}
+  var field3 = String()
+  static var field4 = 4
+  var y: Int! = 45
+}
+
+class C {
+  static var field1 = S()
+  public var field2 = 2
+  private dynamic var field3 = 5
+  @available(macOS 10.12, *) private static dynamic var field4 = 4
+  let field5 = 5
+}
+
+
+
+
+
+
+
+
+
+
+

test/refactoring/ConvertToComputedProperty/Outputs/basic/L4-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1 = 2
+  var field2 = "2"
+  var field3: String {
+return String()
+}
+  static var field4 = 4
+  var y: Int! = 45
+}
+
+class C {
+  static var field1 = S()
+  public var field2 = 2
+  private dynamic var field3 = 5
+  @available(macOS 10.12, *) private static dynamic var field4 = 4
+  let field5 = 5
+}
+
+
+
+
+
+
+
+
+
+
+

test/refactoring/ConvertToComputedProperty/Outputs/basic/L5-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1 = 2
+  var field2 = "2"
+  var field3 = String()
+  static var field4: Int {
+return 4
+}
+  var y: Int! = 45
+}
+
+class C {
+  static var field1 = S()
+  public var field2 = 2
+  private dynamic var field3 = 5
+  @available(macOS 10.12, *) private static dynamic var field4 = 4
+  let field5 = 5
+}
+
+
+
+
+
+
+
+
+
+
+

test/refactoring/ConvertToComputedProperty/Outputs/basic/L6-3.swift.expected

@@ -0,0 +1,28 @@
+struct S {
+  var field1 = 2
+  var field2 = "2"
+  var field3 = String()
+  static var field4 = 4
+  var y: Int! {
+return 45
+}
+}
+
+class C {
+  static var field1 = S()
+  public var field2 = 2
+  private dynamic var field3 = 5
+  @available(macOS 10.12, *) private static dynamic var field4 = 4
+  let field5 = 5
+}
+
+
+
+
+
+
+
+
+
+
+