Merge pull request #289 from seabaylea/nstimezone

Add implementation of NSTimeZone.init() with abbreviation

Author: phausler

Foundation/NSTimeZone.swift

@@ -84,7 +84,13 @@ public class NSTimeZone : NSObject, NSCopying, NSSecureCoding, NSCoding {
     // do NOT follow the POSIX convention (of minutes-west).
     public convenience init(forSecondsFromGMT seconds: Int) { NSUnimplemented() }
 
-    public convenience init?(abbreviation: String) { NSUnimplemented() }
+    public convenience init?(abbreviation: String) {
+        let abbr = abbreviation._cfObject
+        guard let name = unsafeBitCast(CFDictionaryGetValue(CFTimeZoneCopyAbbreviationDictionary(), unsafeBitCast(abbr, to: UnsafePointer<Void>.self)), to: NSString!.self) else {
+            return nil
+        }
+        self.init(name: name._swiftObject , data: nil)
+    }
 
     public func encodeWithCoder(aCoder: NSCoder) {
         if aCoder.allowsKeyedCoding {

TestFoundation/TestNSTimeZone.swift

@@ -26,6 +26,7 @@ class TestNSTimeZone: XCTestCase {
             // Disabled see https://bugs.swift.org/browse/SR-300
             // ("test_abbreviation", test_abbreviation),
             ("test_initializingTimeZoneWithOffset", test_initializingTimeZoneWithOffset),
+            ("test_initializingTimeZoneWithAbbreviation", test_initializingTimeZoneWithAbbreviation),
             // Also disabled due to https://bugs.swift.org/browse/SR-300
             // ("test_systemTimeZoneUsesSystemTime", test_systemTimeZoneUsesSystemTime),
         ]
@@ -45,6 +46,16 @@ class TestNSTimeZone: XCTestCase {
         XCTAssertEqual(seconds, -14400, "GMT-0400 should be -14400 seconds but got \(seconds) instead")
     }
 
+    func test_initializingTimeZoneWithAbbreviation() {
+        // Test invalid timezone abbreviation
+        var tz = NSTimeZone(abbreviation: "XXX")
+        XCTAssertNil(tz)
+        // Test valid timezone abbreviation of "AST" for "America/Halifax"
+        tz = NSTimeZone(abbreviation: "AST")
+        let expectedName = "America/Halifax"
+        XCTAssertEqual(tz?.name, expectedName, "expected name \"\(expectedName)\" is not equal to \"\(tz?.name)\"")
+    }
+    
     func test_systemTimeZoneUsesSystemTime() {
         tzset();
         var t = time(nil)