Change NSURL 'checkResourceIsReachableAndReturnError' to 'checkResourceIsReachable' with throw as Linux does not support Autoreleasing pointers

Author: Sergey Minakov

Foundation/NSURL.swift

@@ -610,25 +610,23 @@ open class NSURL : NSObject, NSSecureCoding, NSCopying {
     */
     /// - Experiment: This is a draft API currently under consideration for official import into Foundation as a suitable alternative
     /// - Note: Since this API is under consideration it may be either removed or revised in the near future
-    open func checkResourceIsReachableAndReturnError(_ error: UnsafeMutablePointer<NSError?>?) -> Bool {
+    // TODO: should be `checkResourceIsReachableAndReturnError` with autoreleased error parameter.
+    // Currently Autoreleased pointers is not supported on Linux.
+    open func checkResourceIsReachable() throws -> Bool {
         guard isFileURL,
             let path = path else {
-                if let error = error {
-                    error.pointee = NSError(domain: NSCocoaErrorDomain,
-                                            code: CocoaError.Code.fileNoSuchFile.rawValue)
-                }
-                return false
+                throw NSError(domain: NSCocoaErrorDomain,
+                              code: CocoaError.Code.fileNoSuchFile.rawValue)
+                //return false
         }
 
         guard FileManager.default.fileExists(atPath: path) else {
-            if let error = error {
-                error.pointee = NSError(domain: NSCocoaErrorDomain,
-                                        code: CocoaError.Code.fileReadNoSuchFile.rawValue,
-                                        userInfo: [
-                                            "NSURL" : self,
-                                            "NSFilePath" : path])
-            }
-            return false
+            throw NSError(domain: NSCocoaErrorDomain,
+                          code: CocoaError.Code.fileReadNoSuchFile.rawValue,
+                          userInfo: [
+                            "NSURL" : self,
+                            "NSFilePath" : path])
+            //return false
         }
 
         return true

Foundation/URL.swift

@@ -931,14 +931,7 @@ public struct URL : ReferenceConvertible, Equatable {
     ///
     /// This method synchronously checks if the resource's backing store is reachable. Checking reachability is appropriate when making decisions that do not require other immediate operations on the resource, e.g. periodic maintenance of UI state that depends on the existence of a specific document. When performing operations such as opening a file or copying resource properties, it is more efficient to simply try the operation and handle failures. This method is currently applicable only to URLs for file system resources. For other URL types, `false` is returned.
     public func checkResourceIsReachable() throws -> Bool {
-        var error: NSError?
-        let result = _url.checkResourceIsReachableAndReturnError(&error)
-        
-        guard error == nil else {
-            throw error!
-        }
-        
-        return result
+        return try _url.checkResourceIsReachable()
     }
 
     // MARK: - Bridging Support

TestFoundation/TestNSURL.swift

@@ -450,19 +450,30 @@ class TestNSURL : XCTestCase {
             XCTFail()
         }
 
-        var nsURL: NSURL? = NSURL(fileURLWithPath: "/usr")
-        var error: NSError?
-        XCTAssertEqual(true, nsURL?.checkResourceIsReachableAndReturnError(&error))
-        XCTAssertNil(error)
+        var nsURL = NSURL(fileURLWithPath: "/usr")
+        XCTAssertEqual(true, try? nsURL.checkResourceIsReachable())
 
-        nsURL = NSURL(string: "https://www.swift.org")
-        XCTAssertEqual(false, nsURL?.checkResourceIsReachableAndReturnError(&error))
-        XCTAssertNotNil(error)
-        error = nil
+        nsURL = NSURL(string: "https://www.swift.org")!
+        do {
+            _ = try nsURL.checkResourceIsReachable()
+            XCTFail()
+        } catch let error as NSError {
+            XCTAssertEqual(NSCocoaErrorDomain, error.domain)
+            XCTAssertEqual(CocoaError.Code.fileNoSuchFile.rawValue, error.code)
+        } catch {
+            XCTFail()
+        }
 
         nsURL = NSURL(fileURLWithPath: "/some_random_path")
-        XCTAssertEqual(false, nsURL?.checkResourceIsReachableAndReturnError(&error))
-        XCTAssertNotNil(error)
+        do {
+            _ = try nsURL.checkResourceIsReachable()
+            XCTFail()
+        } catch let error as NSError {
+            XCTAssertEqual(NSCocoaErrorDomain, error.domain)
+            XCTAssertEqual(CocoaError.Code.fileReadNoSuchFile.rawValue, error.code)
+        } catch {
+            XCTFail()
+        }
     }
 
     func test_copy() {