Diagnose objcImpl members with wrong name

Author: beccadax

include/swift/AST/DiagnosticsSema.def

@@ -1601,6 +1601,15 @@ ERROR(objc_implementation_wrong_category,none,
       "%select{main class interface|category %3}3",
       (DescriptiveDeclKind, ValueDecl *, Identifier, Identifier))
 
+ERROR(objc_implementation_wrong_objc_name,none,
+      "selector %0 for %1 %2 not found in header; did you mean %3?",
+      (ObjCSelector, DescriptiveDeclKind, ValueDecl *, ObjCSelector))
+
+ERROR(objc_implementation_wrong_swift_name,none,
+      "selector %0 used in header by an %1 with a different name; did you "
+      "mean %2?",
+      (ObjCSelector, DescriptiveDeclKind, DeclName))
+
 ERROR(cdecl_not_at_top_level,none,
       "@_cdecl can only be applied to global functions", ())
 ERROR(cdecl_empty_name,none,

lib/Sema/TypeCheckDeclPrimary.cpp

@@ -1245,6 +1245,7 @@ static void checkObjCImplementationMemberAvoidsVTable(ValueDecl *VD) {
 
   auto isNotRelevantInterfaceMember = [&](ValueDecl *member) -> bool {
     return !member->hasClangNode()
+             || member->getAttrs().isUnavailable(VD->getASTContext())
              || VD->isInstanceMember() != member->isInstanceMember();
   };
   assert(!VD->hasClangNode() &&
@@ -1330,6 +1331,32 @@ static void checkObjCImplementationMemberAvoidsVTable(ValueDecl *VD) {
     return;
   }
 
+  auto selectedMethod = *selectedMethodIter;
+  // If the Swift names don't match, suggest correcting the implementation
+  if (selectedMethod->getName() != VD->getName()) {
+    auto diag = diags.diagnose(VD, diag::objc_implementation_wrong_swift_name,
+                               *selectedMethod->getObjCRuntimeName(),
+                               selectedMethod->getDescriptiveKind(),
+                               selectedMethod->getName());
+    fixDeclarationName(diag, VD, selectedMethod->getName());
+  }
+  // If there was no @objc, add one with the implementation's @objc name.
+  else if (!objcAttr) {
+    objcAttr = ObjCAttr::create(VD->getASTContext(),
+                                selectedMethod->getObjCRuntimeName(),
+                                true);
+    VD->getAttrs().add(objcAttr);
+  }
+  // If there was an @objc with the wrong name, diagnose.
+  else if (objcAttr->hasName()
+             && objcAttr->getName() != selectedMethod->getObjCRuntimeName()) {
+    auto diag = diags.diagnose(VD, diag::objc_implementation_wrong_objc_name,
+                               *objcAttr->getName(), VD->getDescriptiveKind(),
+                               VD, *selectedMethod->getObjCRuntimeName());
+    fixDeclarationObjCName(diag, VD, objcAttr->getName(),
+                           selectedMethod->getObjCRuntimeName());
+  }
+
   assert(VD->isObjC());
   assert(isa<DestructorDecl>(VD) || VD->isDynamic() &&
          "@objc decls in @_objcImplementations should be dynamic!");

test/decl/ext/Inputs/objc_implementation.h

@@ -11,13 +11,12 @@
 @end
 
 @interface ObjCClass : ObjCBaseClass
+
 - (void)methodFromHeader1:(int)param;
 - (void)methodFromHeader2:(int)param;
 - (void)methodFromHeader3:(int)param;
 - (void)methodFromHeader4:(int)param;
 
-// FIXME: test case involving swift_name
-
 @property int propertyFromHeader1;
 @property int propertyFromHeader2;
 @property int propertyFromHeader3;
@@ -38,20 +37,31 @@
 @end
 
 @interface ObjCClass (PresentAdditions)
+
 - (void)categoryMethodFromHeader1:(int)param;
 - (void)categoryMethodFromHeader2:(int)param;
 - (void)categoryMethodFromHeader3:(int)param;
 - (void)categoryMethodFromHeader4:(int)param;
 
-// FIXME: test case involving swift_name
-
 @property int categoryPropertyFromHeader1;
 @property int categoryPropertyFromHeader2;
 @property int categoryPropertyFromHeader3;
 @property int categoryPropertyFromHeader4;
 
 @end
 
+@interface ObjCClass (SwiftNameTests)
+
+- (void)methodObjCName1 __attribute__((swift_name("methodSwiftName1()")));
+- (void)methodObjCName2 __attribute__((swift_name("methodSwiftName2()")));
+- (void)methodObjCName3 __attribute__((swift_name("methodSwiftName3()")));
+- (void)methodObjCName4 __attribute__((swift_name("methodSwiftName4()")));
+- (void)methodObjCName5 __attribute__((swift_name("methodSwiftName5()")));
+- (void)methodObjCName6A __attribute__((swift_name("methodSwiftName6A()")));
+- (void)methodObjCName6B __attribute__((swift_name("methodSwiftName6B()")));
+
+@end
+
 @interface ObjCSubclass : ObjCClass
 
 - (void)subclassMethodFromHeader1:(int)param;

test/decl/ext/objc_implementation.swift

@@ -178,6 +178,35 @@
   }
 }
 
+@_objcImplementation(SwiftNameTests) extension ObjCClass {
+  func methodSwiftName1() {
+    // OK, infers `@objc(methodObjCName1)`
+  }
+
+  @objc(methodObjCName2) func methodSwiftName2() {
+    // OK
+  }
+
+  func methodObjCName3() {
+    // expected-error@-1 {{instance method 'methodObjCName3()' does not match any instance method declared in the headers for 'ObjCClass'; did you use the instance method's Swift name?}}
+    // expected-note@-2 {{add 'private' or 'fileprivate' to define an Objective-C-compatible instance method not declared in the header}}
+    // expected-note@-3 {{add 'final' to define a Swift instance method that cannot be overridden}}
+    // FIXME: provide a specialized fix-it for this situation
+  }
+
+  @objc(methodWrongObjCName4) func methodSwiftName4() {
+    // expected-error@-1 {{selector 'methodWrongObjCName4' for instance method 'methodSwiftName4()' not found in header; did you mean 'methodObjCName4'?}} {{9-29=methodObjCName4}}
+  }
+
+  @objc(methodObjCName5) func methodWrongSwiftName5() {
+    // expected-error@-1 {{selector 'methodObjCName5' used in header by an instance method with a different name; did you mean 'methodSwiftName5()'?}} {{31-52=methodSwiftName5}}
+  }
+
+  @objc(methodObjCName6A) func methodSwiftName6B() {
+    // expected-error@-1 {{selector 'methodObjCName6A' used in header by an instance method with a different name; did you mean 'methodSwiftName6A()'?}} {{32-49=methodSwiftName6A}}
+  }
+}
+
 @_objcImplementation extension ObjCClass {}
 // expected-error@-1 {{duplicate implementation of Objective-C class 'ObjCClass'}}