[ConstraintSystem] Don't attempt missing function call diagnostics if

there is no function expression explicitly written in the source code.

Author: hborla

lib/Sema/CSDiagnostics.cpp

@@ -2641,6 +2641,12 @@ void ContextualFailure::tryFixIts(InFlightDiagnostic &diagnostic) const {
 }
 
 bool ContextualFailure::diagnoseMissingFunctionCall() const {
+  // Don't suggest inserting a function call if the function expression
+  // isn't written explicitly in the source code.
+  auto *anchor = getAsExpr(simplifyLocatorToAnchor(getLocator()));
+  if (!anchor || anchor->isImplicit())
+    return false;
+
   if (getLocator()
       ->isLastElement<LocatorPathElt::UnresolvedMemberChainResult>())
     return false;

lib/Sema/CSSimplify.cpp

@@ -3657,15 +3657,17 @@ bool ConstraintSystem::repairFailures(
     if (!fnType)
       return false;
 
+    // If the locator isn't anchored at an expression, or the expression is
+    // implicit, don't try to insert an explicit call into the source code.
+    auto *loc = getConstraintLocator(locator);
+    auto *anchor = getAsExpr(simplifyLocatorToAnchor(loc));
+    if (!anchor || anchor->isImplicit())
+      return false;
+
     // If argument is a function type and all of its parameters have
     // default values, let's see whether error is related to missing
     // explicit call.
     if (fnType->getNumParams() > 0) {
-      auto *loc = getConstraintLocator(locator);
-      auto *anchor = getAsExpr(simplifyLocatorToAnchor(loc));
-      if (!anchor)
-        return false;
-
       auto overload = findSelectedOverloadFor(anchor);
       if (!(overload && overload->choice.isDecl()))
         return false;

test/decl/var/property_wrappers.swift

@@ -1011,6 +1011,17 @@ struct SR_10899_Usage {
   @SR_10899_Wrapper var thing: Bool // expected-error{{property type 'Bool' does not match 'wrappedValue' type 'String'}}
 }
 
+// https://bugs.swift.org/browse/SR-14730
+@propertyWrapper
+struct StringWrappedValue {
+  var wrappedValue: String
+}
+
+struct SR_14730 {
+  // expected-error@+1 {{property type '() -> String' does not match 'wrappedValue' type 'String'}}
+  @StringWrappedValue var value: () -> String
+}
+
 // SR-11061 / rdar://problem/52593304 assertion with DeclContext mismatches
 class SomeValue {
 	@SomeA(closure: { $0 }) var some: Int = 100