commit 35df01994b1f4b8cc93d393520ce51d0c0fadb94
author John Holdsworth <github@johnholdsworth.com> Fri Feb 16 14:32:18 2018 +0000
committer John Holdsworth <github@johnholdsworth.com> Mon Feb 19 11:19:07 2018 +0000
tree 22f4374a8f5dba0d4dfc0ae7ed3c260d75d04d12
parent cd245766ff28f17a754cfb33962d73a013832423

Fix for when key is a String rather than NSString. Otherwise you can get the following crash:

Could not cast value of type 'Swift.AnyHashable' (0x1027b3b10) to 'SwiftFoundation.NSObject' (0x101a56668).
2018-02-16 14:30:46.355774+0000 TestFoundation[7306:8715333] Could not cast value of type 'Swift.AnyHashable' (0x1027b3b10) to 'SwiftFoundation.NSObject' (0x101a56668).
(lldb) up
frame #9: 0x000000010165b114 SwiftFoundation`NSMutableDictionary.subscript.setter(newValue=some, key=Swift.AnyHashable @ 0x00007fff5fbfcd88, self=0x000060800e181fe0) at NSDictionary.swift:649
   646 	        }
   647 	        set {
   648 	            if let val = newValue {
-> 649 	                setObject(val, forKey: key)
   650 	            } else {
   651 	                removeObject(forKey: key)
   652 	            }
(lldb) up
frame #10: 0x00000001004c0443 TestFoundation`static Dictionary.twEncode(data=TestFoundation.TwoWayMirror @ 0x00007fff5fbfce00, self=[Key : Value]) at TwoWayMirror.swift:386
   383 	            #if os(Linux)
   384 	            let key = NSString(string: key as! String)
   385 	            #endif
-> 386 	            dict[key] = TwoWayMirror.encode(mirror: &mirror)
   387 	        }
   388 	        return dict
   389 	    }
(lldb)

Foundation/NSDictionary.swift

diff --git a/Foundation/NSDictionary.swift b/Foundation/NSDictionary.swift
index 4dd44e6..ad5675a 100644
--- a/Foundation/NSDictionary.swift
+++ b/Foundation/NSDictionary.swift
@@ -586,7 +586,7 @@
         guard type(of: self) === NSDictionary.self || type(of: self) === NSMutableDictionary.self else {
             NSRequiresConcreteImplementation()
         }
-        _storage[(aKey as! NSObject)] = _SwiftValue.store(anObject)
+        _storage[_SwiftValue.store(aKey)] = _SwiftValue.store(anObject)
     }
     
     public convenience required init() {

TestFoundation/TestNSDictionary.swift

diff --git a/TestFoundation/TestNSDictionary.swift b/TestFoundation/TestNSDictionary.swift
index b1435d4..a5380de 100644
--- a/TestFoundation/TestNSDictionary.swift
+++ b/TestFoundation/TestNSDictionary.swift
@@ -32,6 +32,7 @@
             ("test_mutableCopying", test_mutableCopying),
             ("test_writeToFile", test_writeToFile),
             ("test_initWithContentsOfFile", test_initWithContentsOfFile),
+            ("test_settingWithStringKey", test_settingWithStringKey),
         ]
     }
         
@@ -222,6 +223,12 @@
         }
     }
 
+    func test_settingWithStringKey() {
+        let dict = NSMutableDictionary()
+        // has crashed in the past
+        dict["stringKey"] = "value"
+    }
+
     private func createTestFile(_ path: String, _contents: Data) -> String? {
         let tempDir = NSTemporaryDirectory() + "TestFoundation_Playground_" + NSUUID().uuidString + "/"
         do {