Clang importer: include subscripts in the Swift name lookup tables.

Author: DougGregor

lib/ClangImporter/ClangImporter.cpp

@@ -709,6 +709,11 @@ void ClangImporter::Implementation::addEntryToLookupTable(
       // Also add the alias, if needed.
       if (importedName.Alias)
         table.addEntry(importedName.Alias, named, effectiveContext);
+
+      // Also add the subscript entry, if needed.
+      if (importedName.IsSubscriptAccessor)
+        table.addEntry(DeclName(SwiftContext, SwiftContext.Id_subscript, { }),
+                       named, effectiveContext);
     }
   }
 
@@ -2259,6 +2264,16 @@ auto ClangImporter::Implementation::importFullName(
                                            /*hasCustomName=*/false);
 
     isFunction = true;
+
+    // Is this one of the accessors for subscripts?
+    if (objcMethod->getMethodFamily() == clang::OMF_None &&
+        objcMethod->isInstanceMethod() &&
+        (objcMethod->getSelector() == objectAtIndexedSubscript ||
+         objcMethod->getSelector() == setObjectAtIndexedSubscript ||
+         objcMethod->getSelector() == objectForKeyedSubscript ||
+         objcMethod->getSelector() == setObjectForKeyedSubscript))
+      result.IsSubscriptAccessor = true;
+
     break;
   }
   }

lib/ClangImporter/ImporterImpl.h

@@ -779,6 +779,9 @@ class LLVM_LIBRARY_VISIBILITY ClangImporter::Implementation
     /// than refuse to import the initializer.
     bool DroppedVariadic = false;
 
+    /// Whether this declaration is a subscript accessor (getter or setter).
+    bool IsSubscriptAccessor = false;
+
     /// For an initializer, the kind of initializer to import.
     CtorInitializerKind InitKind = CtorInitializerKind::Designated;
 

test/IDE/Inputs/swift_name_objc.h

@@ -38,6 +38,7 @@ SWIFT_NAME(SomeProtocol)
 @interface SNSomeClass (Category1) <SNSomeProtocol>
 - (void)categoryMethodWithX:(float)x y:(float)y;
 - (void)categoryMethodWithX:(float)x y:(float)y z:(float)z;
+- (object)objectAtIndexedSubscript:(NSInteger)index;
 @end
 
 @interface SNCollision

test/IDE/dump_swift_lookup_tables_objc.swift

@@ -28,8 +28,10 @@
 // CHECK-NEXT:   instanceMethodWithX --> instanceMethodWithX(_:y:z:)
 // CHECK-NEXT:   method --> method()
 // CHECK-NEXT:   methodWithFloat --> methodWithFloat(_:)
+// CHECK-NEXT:   objectAtIndexedSubscript --> objectAtIndexedSubscript(_:)
 // CHECK-NEXT:   protoInstanceMethodWithX --> protoInstanceMethodWithX(_:y:)
 // CHECK-NEXT:   setAccessibilityFloat --> setAccessibilityFloat(_:)
+// CHECK-NEXT:   subscript --> subscript()
 
 // CHECK:      Full name -> entry mappings:
 // CHECK-NEXT:   CCItem:
@@ -89,10 +91,14 @@
 // CHECK-NEXT:     NSErrorImports: -[NSErrorImports methodAndReturnError:]
 // CHECK-NEXT:   methodWithFloat(_:):
 // CHECK-NEXT:     NSErrorImports: -[NSErrorImports methodWithFloat:error:]
+// CHECK-NEXT:   objectAtIndexedSubscript(_:):
+// CHECK-NEXT:     SNSomeClass: -[SNSomeClass objectAtIndexedSubscript:]
 // CHECK-NEXT:   protoInstanceMethodWithX(_:y:):
 // CHECK-NEXT:     SNSomeProtocol: -[SNSomeProtocol protoInstanceMethodWithX:y:]
 // CHECK-NEXT:   setAccessibilityFloat(_:):
 // CHECK-NEXT:     NSAccessibility: -[NSAccessibility setAccessibilityFloat:]
+// CHECK-NEXT:   subscript():
+// CHECK-NEXT:     SNSomeClass: -[SNSomeClass objectAtIndexedSubscript:]
 
 // CHECK-OMIT-NEEDLESS-WORDS: Base -> full name mappings:
 // CHECK-OMIT-NEEDLESS-WORDS:   instanceMethodWithX --> instanceMethodWithX(_:y:z:)