genstrings fails for Swift calls to NSLocalizedString with more than a key and a comment

Originator:lithium3141
Number:rdar://24770264 Date Originated:22-Feb-2016 09:29 AM
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 7.3 (7D141l) / OS X 10.11.3 (15D21)
Classification:Other Bug Reproducible:Always
 
Summary:
The genstrings utility searches source files for uses of NSLocalizedString(), extracting the key and other information out to a .strings file for localization and internationalization. genstrings can be run on Swift files in addition to Objective-C .h and .m files.

However, invocations of NSLocalizedString() in Swift seem to only be supported by genstrings if they provide a key and a comment, but no other arguments. For example, NSLocalizedString() supports a `value:` argument in Swift; if this is given, an invocation of genstrings on that Swift file will fail, producing the error "Argument is not a literal string."

Steps to Reproduce:
1. Download the attached Swift file
2. Invoke genstrings on this file

Expected Results:
genstrings runs without error. A file Localizable.strings is generated with two keys: "foo" and "bar".

Actual Results:
genstrings runs, but produces an error for the NSLocalizedString() invocation that provides a value. A file Localizable.strings is generated with only the key "foo".

Version:
Xcode 7.3 (7D141l) / OS X 10.11.3 (15D21)

Notes:
http://www.openradar.me/22133811 seems to indicate this has been a problem since at least Xcode 7.0. I tested with Xcode 7.2 and 7.3b3; both produced the same error.

Configuration:
Tested on a mid-2015 MacBook Pro with Retina with a standalone Swift file, but I believe this applies on any project with Swift code, regardless of platform or device.

Comments

genstrings.swift

"The attached Swift file" above has the following contents: 

import Foundation

func shortLocalizedString() -> String {
    return NSLocalizedString("foo", comment: "genstrings Swift test - foo")
}

func longLocalizedString() -> String {
    return NSLocalizedString("bar", value: "<UNLOCALIZED BAR>", comment: "genstrings Swift test - bar")
}

print("\(shortLocalizedString()) \(longLocalizedString())")
By lithium3141 at Feb. 22, 2016, 6:25 p.m. (reply...)

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