Closures Declared Ambiguous until Derived Data Deleted and Project Cleaned

Originator:benvreed
Number:rdar://19367573 Date Originated:1/02/2015
Status:Open Resolved:No
Product:Developer Tools Product Version:6.1.1 (6A2008a)
Classification:Serious Bug Reproducible:Sometimes
 
Summary:
When declaring a closure, I noticed that a simple change causes Xcode to mark it 'ambiguous'. For instance, I changed a println() statement with/without string interpolation.  One compiled normally, and the other failed to compile.  

I'm using the Quick BDD Testing framework, but this does not appear to be related to it.  Rather, it seems to be a problem with the Developer Tools.

An example project with the bug is zipped and attached as well as two screenshots showing the output.

Steps to Reproduce:
1. Create a new Xcode Project
2. Install Quick and Nimble for Testing
3. Attempt to create a beforeEach closure in a QuickConfigurator that prints the metadata.
4. Switch it to be string interpolated, or surround it by other statements.
5. Observe

Expected Results:
No error.

Actual Results:
Error: Ambitious use of 'beforeEach' or other Closure.

Version:
Xcode Version 6.1.1 (6A2008a)
OS X Version 10.10.2 (14C81f)

Notes:
There is a workaround that works...
1. Delete derived data
2. Clean the project

Uploads:
https://dl.dropboxusercontent.com/u/32805057/Archive.zip

Comments


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