Merge pull request #11061 from jckarter/static-key-path-error

Sema: Don't allow key path literals to refer to static members.

Author: jckarter

include/swift/AST/DiagnosticsSema.def

@@ -422,7 +422,7 @@ ERROR(noescape_functiontype_mismatch,none,
 ERROR(expr_keypath_no_objc_runtime,none,
       "'#keyPath' can only be used with the Objective-C runtime", ())
 ERROR(expression_unused_keypath_result,none,
-      "result of '#keyPath' is unused", ())
+      "result of key path is unused", ())
 ERROR(expr_keypath_non_objc_property,none,
       "argument of '#keyPath' refers to non-'@objc' property %0",
       (DeclName))
@@ -434,14 +434,17 @@ ERROR(expr_keypath_type_of_property,none,
       "cannot refer to type member %0 within instance of type %1",
       (DeclName, Type))
 ERROR(expr_keypath_generic_type,none,
-      "'#keyPath' cannot refer to generic type %0", (DeclName))
+      "key path cannot refer to generic type %0", (DeclName))
 ERROR(expr_keypath_not_property,none,
-      "'#keyPath' cannot refer to %0 %1", (DescriptiveDeclKind, DeclName))
+      "key path cannot refer to %0 %1", (DescriptiveDeclKind, DeclName))
 ERROR(expr_keypath_mutating_getter,none,
-      "'#keyPath' cannot refer to %0, which has a mutating getter",
+      "key path cannot refer to %0, which has a mutating getter",
+      (DeclName))
+ERROR(expr_keypath_static_member,none,
+      "key path cannot refer to static member %0",
       (DeclName))
 ERROR(expr_keypath_empty,none,
-      "empty '#keyPath' does not refer to a property", ())
+      "empty key path does not refer to a property", ())
 ERROR(expr_unsupported_objc_key_path_component,none,
       "an Objective-C key path cannot contain "
       "%select{BAD|subscript|BAD|BAD|optional-forcing|optional-chaining|BAD} "
@@ -459,7 +462,7 @@ ERROR(expr_swift_keypath_not_starting_with_type,none,
 ERROR(expr_swift_keypath_unimplemented_component,none,
       "key path support for %0 components is not implemented", (StringRef))
 ERROR(expr_smart_keypath_value_covert_to_contextual_type,none,
-      "KeyPath value type %0 cannot be converted to contextual type %1",
+      "key path value type %0 cannot be converted to contextual type %1",
       (Type, Type))
 ERROR(expr_swift_keypath_empty, none,
       "key path must have at least one component", ())

lib/Sema/CSApply.cpp

@@ -3992,6 +3992,13 @@ namespace {
                              diag::expr_keypath_mutating_getter,
                              property->getFullName());
             }
+            
+            // Key paths don't currently support static members.
+            if (varDecl->isStatic()) {
+              cs.TC.diagnose(origComponent.getLoc(),
+                             diag::expr_keypath_static_member,
+                             property->getFullName());
+            }
           }
 
           // Unwrap if we needed to look through an IUO to find the

test/Constraints/diagnostics.swift

@@ -971,9 +971,9 @@ class SR_4692_b {
 
 struct R32101765 { let prop32101765 = 0 }
 let _: KeyPath<R32101765, Float> = \.prop32101765
-// expected-error@-1 {{KeyPath value type 'Int' cannot be converted to contextual type 'Float'}}
+// expected-error@-1 {{key path value type 'Int' cannot be converted to contextual type 'Float'}}
 let _: KeyPath<R32101765, Float> = \R32101765.prop32101765
-// expected-error@-1 {{KeyPath value type 'Int' cannot be converted to contextual type 'Float'}}
+// expected-error@-1 {{key path value type 'Int' cannot be converted to contextual type 'Float'}}
 let _: KeyPath<R32101765, Float> = \.prop32101765.unknown
 // expected-error@-1 {{type 'Int' has no member 'unknown'}}
 let _: KeyPath<R32101765, Float> = \R32101765.prop32101765.unknown

test/expr/unary/keypath/keypath-objc.swift

@@ -113,8 +113,8 @@ func testSemanticErrors() {
   let _: String = #keyPath(AnyObject.ambiguous) // expected-error{{ambiguous reference to member 'ambiguous'}}
   let _: String = #keyPath(C.nonObjC) // expected-error{{argument of '#keyPath' refers to non-'@objc' property 'nonObjC'}}
   let _: String = #keyPath(A.propArray.UTF8View) // expected-error{{type 'String' has no member 'UTF8View'}}
-  let _: String = #keyPath(A.someMethod) // expected-error{{'#keyPath' cannot refer to instance method 'someMethod()'}}
-  let _: String = #keyPath(A) // expected-error{{empty '#keyPath' does not refer to a property}}
+  let _: String = #keyPath(A.someMethod) // expected-error{{key path cannot refer to instance method 'someMethod()'}}
+  let _: String = #keyPath(A) // expected-error{{empty key path does not refer to a property}}
   let _: String = #keyPath(A.propDict.anyKeyName.unknown) // expected-error{{type 'B' has no member 'unknown'}}
   let _: String = #keyPath(A.propNSDict.anyKeyName.unknown) // expected-error{{type 'AnyObject' has no member 'unknown'}}
 }

test/expr/unary/keypath/keypath.swift

@@ -364,6 +364,21 @@ func testLabeledSubscript() {
   let _ = \AA.[keyPath: \AA.[labeled: 0]] // expected-error{{}}
 }
 
+func testInvalidKeyPathComponents() {
+  let _ = \.{return 0} // expected-error* {{}}
+}
+
+class X {
+  class var a: Int { return 1 }
+  static var b = 2
+}
+
+func testStaticKeyPathComponent() {
+  _ = \X.a // expected-error{{}}
+  _ = \X.Type.a // expected-error{{cannot refer to static member}}
+  _ = \X.b // expected-error{{}}
+  _ = \X.Type.b // expected-error{{cannot refer to static member}}
+}
 
 func testSyntaxErrors() { // expected-note{{}}
   _ = \.  ; // expected-error{{expected member name following '.'}}