[ClangImporter] Don't put method redeclarations in a member list.

Previously we'd try to put the same method into the list of members multiple
times--once for each redeclaration in the @interface. This led to an
assertion failure.

Checking the canonical decl isn't super cheap, but the ObjCMethodDecl
redeclaration infrastructure seems to be fairly broken. We can revisit this
later.

There's also a test for what happens when categories get involved. I'm not
convinced this is correct behavior, either, and will file an additional bug
to look into that at some point.

rdar://problem/19039485

Swift SVN r24129

lib/ClangImporter/ImportDecl.cpp

@@ -3848,7 +3848,7 @@ namespace {
       for (auto m = decl->decls_begin(), mEnd = decl->decls_end();
            m != mEnd; ++m) {
         auto nd = dyn_cast<clang::NamedDecl>(*m);
-        if (!nd)
+        if (!nd || nd != nd->getCanonicalDecl())
           continue;
 
         auto member = Impl.importDecl(nd);
@@ -3865,11 +3865,6 @@ namespace {
           continue;
         }
 
-        // If this member is a method that is a getter or setter for a property
-        // that was imported, don't add it to the list of members so it won't
-        // be found by name lookup. This eliminates the ambiguity between
-        // property names and getter names (by choosing to only have a
-        // variable).
         if (auto objcMethod = dyn_cast<clang::ObjCMethodDecl>(nd)) {
           // If there is a special declaration associated with this member,
           // add it now.
@@ -3906,6 +3901,11 @@ namespace {
           // Import explicit properties as instance properties, not as separate
           // getter and setter methods.
           if (!Impl.isAccessibilityDecl(objcMethod)) {
+            // If this member is a method that is a getter or setter for a
+            // propertythat was imported, don't add it to the list of members
+            // so it won't be found by name lookup. This eliminates the
+            // ambiguity between property names and getter names (by choosing
+            // to only have a variable).
             if (objcMethod->isPropertyAccessor()) {
               auto prop = objcMethod->findPropertyDecl(/*checkOverrides=*/false);
               assert(prop);

test/ClangModules/Inputs/custom-modules/ObjCParseExtras.h

@@ -92,3 +92,10 @@ __weak id globalWeakVar;
 @interface DeprecatedFactoryMethod
 + (instancetype)deprecatedFactoryMethod __attribute__((deprecated("use something newer")));
 @end
+
+
+@interface RepeatedMembers : NSObject
+- (void)repeatedMethod;
+- (void)anotherMethod;
+- (void)repeatedMethod __attribute__((deprecated("use something newer")));
+@end

test/ClangModules/objc_parse.swift

@@ -455,3 +455,7 @@ func testFactoryMethodAvailability() {
   let _ = DeprecatedFactoryMethod() // expected-error{{'init()' is unavailable: use something newer}}
 }
 
+func testRepeatedMembers(obj: RepeatedMembers) {
+  obj.repeatedMethod()
+}
+

test/IDE/Inputs/mock-sdk/Foo.annotated.txt

@@ -254,3 +254,17 @@ class <loc>FooClassDerived</loc> : <ref:Class>FooClassBase</ref>, <ref:Protocol>
 <decl:TypeAlias>typealias <loc>FooCFTypeRef</loc> = <ref:Class>FooCFType</ref></decl>
 <decl:Func>@availability(*, unavailable, message="Core Foundation objects are automatically memory managed")
 func <loc>FooCFTypeRelease(_: <ref:Class>FooCFType</ref>!)</loc></decl>
+<decl:Class>class <loc>FooRepeatedMembers</loc> : <ref:Class>FooClassBase</ref> {
+  <decl:Func>func <loc>repeatedMethod()</loc></decl>
+  <decl:Func>func <loc>anotherMethod()</loc></decl>
+  <decl:Constructor><loc>init!()</loc></decl>
+  <decl:Constructor>convenience <loc>init!(float f: <ref:Struct>Float</ref>)</loc></decl>
+}</decl>
+<decl:Extension>extension <ref:Class><loc>FooRepeatedMembers</ref></loc> {
+  <decl:Var>var <loc>repeatedPropertyInCategory</loc>: <ref:Struct>Int32</ref></decl>
+  <decl:Func>func <loc>repeatedMethodInCategory()</loc></decl>
+  <decl:Var>var <loc>repeatedPropertyFromCategory</loc>: <ref:Struct>Int32</ref></decl>
+  <decl:Func>func <loc>repeatedMethodFromCategory()</loc></decl>
+}</decl>
+<decl:Extension>extension <ref:Class><loc>FooRepeatedMembers</ref></loc> {
+}</decl>

test/IDE/Inputs/mock-sdk/Foo.framework/Headers/Foo.h

@@ -260,4 +260,27 @@ struct _InternalStruct {
 typedef struct __FooCFType *FooCFTypeRef;
 void FooCFTypeRelease(FooCFTypeRef);
 
+
+@interface FooRepeatedMembers : FooClassBase
+- (void)repeatedMethod;
+- (void)anotherMethod;
+- (void)repeatedMethod;
+
+@property int repeatedPropertyInCategory;
+- (void)repeatedMethodInCategory;
+@end
+
+@interface FooRepeatedMembers (Category)
+@property int repeatedPropertyInCategory;
+- (void)repeatedMethodInCategory;
+
+@property int repeatedPropertyFromCategory;
+- (void)repeatedMethodFromCategory;
+@end
+
+@interface FooRepeatedMembers (AnotherCategory)
+@property int repeatedPropertyFromCategory;
+- (void)repeatedMethodFromCategory;
+@end
+
 #endif /* ! __FOO_H__ */

test/IDE/Inputs/mock-sdk/Foo.printed.recursive.txt

@@ -254,6 +254,20 @@ class FooUnavailableMembers : FooClassBase {
 typealias FooCFTypeRef = FooCFType
 @availability(*, unavailable, message="Core Foundation objects are automatically memory managed")
 func FooCFTypeRelease(_: FooCFType!)
+class FooRepeatedMembers : FooClassBase {
+  func repeatedMethod()
+  func anotherMethod()
+  init!()
+  convenience init!(float f: Float)
+}
+extension FooRepeatedMembers {
+  var repeatedPropertyInCategory: Int32
+  func repeatedMethodInCategory()
+  var repeatedPropertyFromCategory: Int32
+  func repeatedMethodFromCategory()
+}
+extension FooRepeatedMembers {
+}
 func fooSubFunc1(a: Int32) -> Int32
 struct FooSubEnum1 {
   init(_ value: UInt32)

test/IDE/Inputs/mock-sdk/Foo.printed.txt

@@ -308,3 +308,21 @@ class FooUnavailableMembers : FooClassBase {
 typealias FooCFTypeRef = FooCFType
 @availability(*, unavailable, message="Core Foundation objects are automatically memory managed")
 func FooCFTypeRelease(_: FooCFType!)
+
+class FooRepeatedMembers : FooClassBase {
+  func repeatedMethod()
+  func anotherMethod()
+  init!()
+  convenience init!(float f: Float)
+}
+
+extension FooRepeatedMembers {
+  var repeatedPropertyInCategory: Int32
+  func repeatedMethodInCategory()
+  
+  var repeatedPropertyFromCategory: Int32
+  func repeatedMethodFromCategory()
+}
+
+extension FooRepeatedMembers {
+}

test/IDE/complete_from_clang_framework.swift

@@ -144,7 +144,7 @@ func testCompleteModuleQualifiedFoo2() {
   Foo#^CLANG_QUAL_FOO_2^#
 // If the number of results below changes, then you need to add a result to the
 // list below.
-// CLANG_QUAL_FOO_2: Begin completions, 61 items
+// CLANG_QUAL_FOO_2: Begin completions, 62 items
 // CLANG_QUAL_FOO_2-DAG: Decl[Class]/OtherModule:        .FooClassBase[#FooClassBase#]{{$}}
 // CLANG_QUAL_FOO_2-DAG: Decl[Class]/OtherModule:        .FooClassDerived[#FooClassDerived#]{{$}}
 // CLANG_QUAL_FOO_2-DAG: Decl[Class]/OtherModule:        .ClassWithInternalProt[#ClassWithInternalProt#]{{$}}
@@ -206,6 +206,7 @@ func testCompleteModuleQualifiedFoo2() {
 // CLANG_QUAL_FOO_2-DAG:  Decl[Class]/OtherModule:            .FooUnavailableMembers[#FooUnavailableMembers#]
 // CLANG_QUAL_FOO_2-DAG: Decl[TypeAlias]/OtherModule:    .FooTypedef1[#Int32#]{{$}}
 // CLANG_QUAL_FOO_2-DAG:   Decl[TypeAlias]/OtherModule:        .FooCFTypeRef[#FooCFType#]{{$}}
+// CLANG_QUAL_FOO_2-DAG:  Decl[Class]/OtherModule: .FooRepeatedMembers[#FooRepeatedMembers#]{{$}}
 // CLANG_QUAL_FOO_2: End completions
 }