Merge pull request #905 from johnno1962a/master

Author: swift-ci

Foundation/NSData.swift

@@ -950,10 +950,8 @@ open class NSMutableData : NSData {
     }
 
     open func replaceBytes(in range: NSRange, withBytes replacementBytes: UnsafeRawPointer?, length replacementLength: Int) {
-        if let replacementBytes = replacementBytes {
-            let bytePtr = replacementBytes.bindMemory(to: UInt8.self, capacity: replacementLength)
-            CFDataReplaceBytes(_cfMutableObject, CFRangeMake(range.location, range.length), bytePtr, replacementLength)
-        }
+        let bytePtr = replacementBytes?.bindMemory(to: UInt8.self, capacity: replacementLength)
+        CFDataReplaceBytes(_cfMutableObject, CFRangeMake(range.location, range.length), bytePtr, replacementLength)
     }
 }
 

TestFoundation/TestNSData.swift

@@ -87,6 +87,7 @@ class TestNSData: XCTestCase {
             ("test_rangeOfData",test_rangeOfData),
             ("test_initMutableDataWithLength", test_initMutableDataWithLength),
             ("test_replaceBytes", test_replaceBytes),
+            ("test_replaceBytesWithNil", test_replaceBytesWithNil),
             ("test_initDataWithCapacity", test_initDataWithCapacity),
             ("test_initDataWithCount", test_initDataWithCount),
             ("test_emptyStringToData", test_emptyStringToData),
@@ -426,6 +427,17 @@ class TestNSData: XCTestCase {
         XCTAssertEqual(mData, expected)
     }
 
+    func test_replaceBytesWithNil() {
+        func makeData(_ data: [UInt8]) -> NSMutableData {
+            return NSMutableData(bytes: data, length: data.count)
+        }
+
+        let mData = makeData([1, 2, 3, 4, 5])
+        mData.replaceBytes(in: NSMakeRange(1, 3), withBytes: nil, length: 0)
+        let expected = makeData([1, 5])
+        XCTAssertEqual(mData, expected)
+    }
+
     func test_initDataWithCapacity() {
         let data = Data(capacity: 123)
         XCTAssertEqual(data.count, 0)