[cs] extract computed property fix-it into separate method

Author: theblixguy

lib/Sema/CSDiag.cpp

@@ -2323,11 +2323,10 @@ bool FailureDiagnosis::diagnoseContextualConversionError(
         !isUnresolvedOrTypeVarType(srcFT->getResult()) &&
         CS.TC.isConvertibleTo(srcFT->getResult(), contextualType, CS.DC)) {
 
-      auto locator = CS.getConstraintLocator(expr);
-      auto extendedLocator =
-          CS.getConstraintLocator(locator, ConstraintLocator::ContextualType);
-      ContextualFailure failure = ContextualFailure(
-          nullptr, CS, srcFT, contextualType, extendedLocator);
+      auto locator =
+          CS.getConstraintLocator(expr, ConstraintLocator::ContextualType);
+      ContextualFailure failure =
+          ContextualFailure(nullptr, CS, srcFT, contextualType, locator);
       auto diagnosed = failure.diagnoseAsError();
       assert(diagnosed && "Failed to produce contextual failure diagnostic");
       (void)diagnosed;

lib/Sema/CSDiagnostics.cpp

@@ -1350,6 +1350,42 @@ bool ContextualFailure::diagnoseMissingFunctionCall() const {
       .highlight(anchor->getSourceRange())
       .fixItInsertAfter(anchor->getEndLoc(), "()");
 
+  if (isa<ClosureExpr>(getAnchor())) {
+    tryComputedPropertyFixIts(TC, anchor, getDC());
+  }
+
+  return true;
+}
+
+bool ContextualFailure::trySequenceSubsequenceFixIts(InFlightDiagnostic &diag,
+                                                     ConstraintSystem &CS,
+                                                     Type fromType, Type toType,
+                                                     Expr *expr) {
+  if (!CS.TC.Context.getStdlibModule())
+    return false;
+
+  auto String = CS.TC.getStringType(CS.DC);
+  auto Substring = CS.TC.getSubstringType(CS.DC);
+
+  if (!String || !Substring)
+    return false;
+
+  // Substring -> String conversion
+  // Wrap in String.init
+  if (fromType->isEqual(Substring)) {
+    if (toType->isEqual(String)) {
+      auto range = expr->getSourceRange();
+      diag.fixItInsert(range.Start, "String(");
+      diag.fixItInsertAfter(range.End, ")");
+      return true;
+    }
+  }
+
+  return false;
+}
+
+void ContextualFailure::tryComputedPropertyFixIts(TypeChecker &TC, Expr *expr,
+                                                  DeclContext *dc) {
   // It is possible that we're looking at a stored property being
   // initialized with a closure. Something like:
   //
@@ -1359,23 +1395,17 @@ bool ContextualFailure::diagnoseMissingFunctionCall() const {
   // property into a computed property. If the variable is immutable, then
   // replace the 'let' with a 'var'.
 
-  if (getAnchor() && !isa<ClosureExpr>(getAnchor())) {
-    return true;
-  }
-
-  // First, check if the variable is declared top level or not. If it is
-  // not, then it means we're inside a decl like a class or an extension.
   PatternBindingDecl *PBD = nullptr;
 
-  if (auto TLCD = dyn_cast<TopLevelCodeDecl>(getDC())) {
+  if (auto TLCD = dyn_cast<TopLevelCodeDecl>(dc)) {
     if (TLCD->getBody()->isImplicit()) {
       if (auto decl = TLCD->getBody()->getElement(0).dyn_cast<Decl *>()) {
         if (auto binding = dyn_cast<PatternBindingDecl>(decl)) {
           PBD = binding;
         }
       }
     }
-  } else if (auto PBI = dyn_cast<PatternBindingInitializer>(getDC())) {
+  } else if (auto PBI = dyn_cast<PatternBindingInitializer>(dc)) {
     PBD = PBI->getBinding();
   }
 
@@ -1387,7 +1417,7 @@ bool ContextualFailure::diagnoseMissingFunctionCall() const {
           !VD->getAttrs().getAttribute<DynamicReplacementAttr>() &&
           entry.getInit() && isa<ClosureExpr>(entry.getInit())) {
         auto diag =
-            TC.diagnose(anchor->getLoc(), diag::extension_stored_property_fixit,
+            TC.diagnose(expr->getLoc(), diag::extension_stored_property_fixit,
                         VD->getName());
         diag.fixItRemove(entry.getEqualLoc());
 
@@ -1397,35 +1427,6 @@ bool ContextualFailure::diagnoseMissingFunctionCall() const {
       }
     }
   }
-
-  return true;
-}
-
-bool ContextualFailure::trySequenceSubsequenceFixIts(InFlightDiagnostic &diag,
-                                                     ConstraintSystem &CS,
-                                                     Type fromType, Type toType,
-                                                     Expr *expr) {
-  if (!CS.TC.Context.getStdlibModule())
-    return false;
-
-  auto String = CS.TC.getStringType(CS.DC);
-  auto Substring = CS.TC.getSubstringType(CS.DC);
-
-  if (!String || !Substring)
-    return false;
-
-  // Substring -> String conversion
-  // Wrap in String.init
-  if (fromType->isEqual(Substring)) {
-    if (toType->isEqual(String)) {
-      auto range = expr->getSourceRange();
-      diag.fixItInsert(range.Start, "String(");
-      diag.fixItInsertAfter(range.End, ")");
-      return true;
-    }
-  }
-
-  return false;
 }
 
 bool AutoClosureForwardingFailure::diagnoseAsError() {

lib/Sema/CSDiagnostics.h

@@ -671,6 +671,10 @@ class ContextualFailure final : public FailureDiagnostic {
   static bool trySequenceSubsequenceFixIts(InFlightDiagnostic &diag,
                                            ConstraintSystem &CS, Type fromType,
                                            Type toType, Expr *expr);
+  /// Try to add a fix-it to convert a stored property into a computed
+  /// property
+  static void tryComputedPropertyFixIts(TypeChecker &TC, Expr *expr,
+                                        DeclContext *dc);
 
 private:
   Type resolve(Type rawType) {

lib/Sema/CSSimplify.cpp

@@ -1990,7 +1990,8 @@ repairFailures(ConstraintSystem &cs, Type lhs, Type rhs,
   }
 
   case ConstraintLocator::ContextualType: {
-    if (lhs->is<FunctionType>() && !rhs->is<AnyFunctionType>()) {
+    if (lhs->is<FunctionType>() && !rhs->is<AnyFunctionType>() &&
+        isa<ClosureExpr>(anchor)) {
       auto *fix = ContextualMismatch::create(cs, lhs, rhs,
                                              cs.getConstraintLocator(locator));
       conversionsOrFixes.push_back(fix);

test/expr/closure/closures.swift

@@ -20,8 +20,7 @@ var closure5 : (Double) -> Int = {
 
 var closure6 = $0  // expected-error {{anonymous closure argument not contained in a closure}}
 
-var closure7 : Int =
-   { 4 }  // expected-error {{function produces expected type 'Int'; did you mean to call it with '()'?}} {{9-9=()}}
+var closure7 : Int = { 4 }  // expected-error {{function produces expected type 'Int'; did you mean to call it with '()'?}} {{27-27=()}} // expected-note {{Remove '=' to make 'closure7' a computed property}}{{20-22=}}
 
 var capturedVariable = 1
 var closure8 = { [capturedVariable] in