FileManager: improve compatibility for setAttributes

`setAttributes(_:ofItemAtPath:)` and friends should not `fatalError`
when encountering an attribute which cannot be set.  Instead, we should
ignore those to match the behaviour of the reference implementation.
This should allow us to properly enable some test cases in swift-driver.

Author: compnerd

Sources/Foundation/FileManager.swift

@@ -450,7 +450,7 @@ open class FileManager : NSObject {
                     throw NSError(domain: NSCocoaErrorDomain, code: CocoaError.fileWriteUnknown.rawValue)
 
                 default:
-                    fatalError("This attribute is unknown or cannot be set: \(attribute)")
+                    break
                 }
             }
 

Tests/Foundation/Tests/TestFileManager.swift

@@ -1259,6 +1259,24 @@ class TestFileManager : XCTestCase {
         XCTAssertFalse(fm.contentsEqual(atPath: testDir1.path, andPath: testDir2.path))
     }
 
+    func test_setInvalidFileAttributes() throws {
+        let path = "\(NSTemporaryDirectory())test_setInvalidFileAttributes\(NSUUID().uuidString)"
+        let FM = FileManager.default
+
+        try? FM.removeItem(atPath: path)
+        XCTAssertTrue(FM.createFile(atPath: path, contents: Data(), attributes: nil))
+
+        do {
+            try FM.setAttributes([
+                .size: NSNumber(value: Int16(16)),
+                .systemNumber: NSNumber(value: Int16(32)),
+                .systemFileNumber: NSNumber(value: Int16(48)),
+            ], ofItemAtPath: path)
+        } catch {
+            XCTFail("\(error)")
+        }
+    }
+
     func test_copyItemsPermissions() throws {
         let fm = FileManager.default
         let tmpDir = fm.temporaryDirectory.appendingPathComponent("test_copyItemsPermissions")
@@ -2024,6 +2042,7 @@ VIDEOS=StopgapVideos
             ("test_displayNames", test_displayNames),
             ("test_getItemReplacementDirectory", test_getItemReplacementDirectory),
             ("test_contentsEqual", test_contentsEqual),
+            ("test_setInvalidFileAttributes", test_setInvalidFileAttributes),
             /* ⚠️  */ ("test_replacement", testExpectedToFail(test_replacement,
             /* ⚠️  */     "<https://bugs.swift.org/browse/SR-10819> Re-enable Foundation test TestFileManager.test_replacement")),
             /* ⚠️  */("test_concurrentGetItemReplacementDirectory", testExpectedToFail(test_concurrentGetItemReplacementDirectory, "Intermittent SEGFAULT: rdar://84519512")),