Open Radar

 
Summary:
Frameworks that contain Objective-C fail to import on the Swift REPL. That makes it hard to interactively work with own and 3rd-party libraries we use.

In particular:

- BUG: Cannot import into the REPL a mixed-source framework "Foo.framework" created with the standard Cocoa Framework template. The REPL (run as "swift -F path/to/framework") clearly finds the framework but fails and soon crashes when trying to "import Foo".

- EXPECTED: Can import the above framework into a Swift script (run as "swift -F path/to/framework Test.swift").

- EXPECTED: Can import and dynamically link the framework in a Swift file compiled with "swiftc -F path/to/framework Test.swift -o Test" and run with "DYLD_FRAMEWORK_PATH=path/to/framework ./Test".

- EXPECTED: Can import and dynamically link the framework in a compiled Swift project.

- SURPRISINGLY: Can import the same framework as soon as all C headers are removed from the target!

Steps to Reproduce:
Grab and build the attached files. In Terminal.app, "cd" to the project directory and run the commands:

```
# (1) Succeeds:
echo 'import Foo; foo()' | xcrun -sdk macosx swiftc -F Mixed - -o Test && DYLD_FRAMEWORK_PATH=Mixed ./Test

# (2) Fails:
echo 'import Foo; foo()' | swift -F Mixed

# (3) Fails likewise:
echo 'import Foo; foo()' | xcrun -sdk macosx swift -F Mixed

# (4) Succeeds, but contains no C headers:
echo 'import Foo; foo()' | swift -F Swift
```

TO RECREATE THE ATTACHMENT:

1. In Xcode (e.g. 6.3 beta 2), create a new project.
2. Choose "Cocoa Framework" under OS X / Framework & Library.
3. Language option Swift. (But happens with Objective-C as well.)
4. Add a Swift file to the project, and a public function.
5. Check that Defines Module is set in Build Settings.
6. Build.

TO RECREATE THE SWIFT-ONLY FRAMEWORK:

1. Uncheck "Target Membership" for the file "Foo.h".
2. Build.

Expected Results:
Expected the import to work when the C header was present.

Actual Results:
(1) prints:

```
It works!
```

(2) and (3) fail with the error:

```
Welcome to Swift version 1.2. Type :help for assistance.
repl.swift:1:8: error: cannot load underlying module for 'Foo'
import Foo; foo()
       ^
A fatal parse error has occurred.  LLDB may become unstable; please restart your debug session as soon as possible.
```

(4) prints:

```
Welcome to Swift version 1.2. Type :help for assistance.
It works!
```

Version:
Happens in both:
- Xcode 6.2 (6C131e)
- Xcode 6.3 beta 2 (6D532l)

Notes:
I asked about this bug in the Developer Forums, https://devforums.apple.com/message/1108998#1108998

Configuration:
Happens in all OS X & Xcode configurations I've tested.

Attachments:
'Foo.zip' was successfully uploaded.