Alt-clicking on members of generic arrays leads to "internal error"

Originator:daniel
Number:rdar://29439232 Date Originated:2016-11-30
Status:Open (Duplicate of 29053290) Resolved:
Product:Xcode Product Version:8.1 (8B62)
Classification: Reproducible:always
 
Summary:
When trying to get the documentation popup for an Array.append, the Xcode source code editor produces an internal error instead of the actual help text.

Steps to Reproduce:
1. open Xcode
2. create a new playground
3. paste the following code:

class GenericClass<Item> {
    var items = [Item]()

    func append(item: Item) {
        items.append(item)
    }
}

4. alt-click on the append word in items.append
5. notice the "No Quick Help" popup
6. click anywhere to close the popup
7. alt-click again on the append word in items.append

Expected Results:
* After steps 4 and 7, the quick help for Array.append(_:) should be shown.

Actual Results:
* After steps 4 and 7, the "No Quick Help" banner is shown.
* The "An internal error occurred. Source editor functionality is limited. Attempting to restore..." message banner is shown after step 7.

Version:
Xcode Version 8.1 (8B62), macOS 10.12.1 (16B2555)

Notes:


Configuration:
This does occur in both Swift playgrounds and iOS apps.

Attachments:

Comments


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