Re-enable NSCoder encodeInt/decodeInt in Swift

[parkera]

What's in this pull request?

When we worked on the first version of naming fixes to the automatic import into Swift, we chose to make -[NSCoder encodeInt:forKey:] unavailable, to avoid a conflict with -[NSCoder encodeInt32:forKey:], as they would end up with the same name in Swift.

However, if you wish to subclass NSCoder in Swift, then you have to override this method. If it is unavailable, then you cannot do so, and if anyone that is encoded using this coder calls it, NSCoder will throw an exception. These methods are abstract in that class:

- (void)encodeInt:(int)intv forKey:(NSString *)key;
- (void)encodeInt32:(int32_t)intv forKey:(NSString *)key;
- (void)encodeInt64:(int64_t)intv forKey:(NSString *)key;

Therefore, we are bringing the method back, but with a slightly different name to resolve the ambiguity.

Import the C integer primitive encode and decode methods as:

extension NSCoder {
    func encodeCInt(_ value: Int32, forKey key: String) // ObjC: -encodeInt:forKey:
    func decodeCInt(forKey key: String) -> Int32 // ObjC: -decodeIntForKey:
}

This will join the existing family of methods:

extension NSCoder {
    func encode(_ value: Int32, forKey key: String) // ObjC: -encodeInt32:forKey:
    func encode(_ value: Int64, forKey key: String) // ObjC: -encodeInt64:forKey:
    func encode(_ value: Int, forKey key: String) // ObjC: -encodeInteger:forKey:

    func decodeInt32(forKey key: String) -> Int32 // ObjC: -decodeInt32ForKey:
    func decodeInt64(forKey key: String) -> Int64 // ObjC: -decodeInt32ForKey:
    func decodeInteger(forKey key: String) -> Int // ObjC: -decodeIntegerForKey:
}

We did not choose to rename Integer to Int in our APIs for coding.

We will continue to make these two functions unavailable on NSKeyedArchiver and NSKeyedUnarchiver, to avoid confusion with the other encode/decode methods that use integers.

Resolved bug number:

rdar://problem/27425997

---

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[parkera]

@swift-ci Please test and merge

[johnspurlock]

Thanks Tony

[parkera]

Thank you for finding this and letting me know!

[johnspurlock]

Did this fix land in the swift version as of xcode beta 4?

Apple Swift version 3.0 (swiftlang-800.0.41.2 clang-800.0.36)

[parkera]

No, Xcode beta 4 used about the same version of the overlay as beta 3 did, due to the numerous pending changes in swift's master branch between the two. This change will be in the next beta, or you can try it out with the daily snapshots (that would be a great way to verify).

[johnspurlock]

Ok I'll wait for the next beta then, thanks

[johnspurlock]

Doesn't look like the fix is in xcode beta 5. Tony, can you confirm?

Apple Swift version 3.0 (swiftlang-800.0.42.1 clang-800.0.36.1)

[parkera]

I'm not sure at this point; the change is clearly in the swift-3.0-branch so I'm not sure why it's not making it into the seeds. Can you double check with a swift 3 snapshot?

[jckarter]

Beta 5 has the same compiler and overlays as 4, for the most part. You should be able to try a snapshot toolchain from swift.org, though.

[johnspurlock]

Ah ok - that would explain why the beta 4 -> beta 5 migration did not require any corresponding changes on my side this time. Thanks, I suspected I had a bad installation at first.

[johnspurlock]

Verified fixed in beta 6 with the new encodeCInt methods, thanks.

Apple Swift version 3.0 (swiftlang-800.0.43.6 clang-800.0.38)