[Webkit-unassigned] [Bug 143577] New: Web Inspector: cannot set breakpoints in IIFE closures via GUI

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=143577

            Bug ID: 143577
           Summary: Web Inspector: cannot set breakpoints in IIFE closures
                    via GUI
    Classification: Unclassified
           Product: WebKit
           Version: 528+ (Nightly build)
          Hardware: All
                OS: All
            Status: NEW
          Severity: Normal
          Priority: P2
         Component: Web Inspector
          Assignee: webkit-unassigned at lists.webkit.org
          Reporter: joey at kidfixit.com
                CC: graouts at webkit.org, joepeck at webkit.org,
                    jonowells at apple.com, mattbaker at apple.com,
                    nvasilyev at apple.com, timothy at apple.com,
                    webkit-bug-importer at group.apple.com

Occasionally I need to tear into readonly remote-hosted JS code to isolate and report bugs on webapps I use.

Single-page-application sites now commonly enclose their entire app code into an IIFE, adding nothing to the global scope that can be probed using the console.
  (function () { true; }() )
or
  !function(){ true; }()

Web Inspector will let me click to set breakpoints inside IIFEs but they will never fire when the site feature that was breakpointed is engaged.
Breakpointing the same lines in Chrome, Opera and Firefox works and provides console access to the stack inside the IIFE closure.

It makes no difference whether the script file was minified (and subsequently prettified by Web Inspector) or not.
None of the sites I am debugging have source-maps available.

The only way I can currently debug such sites on Safari is by saving a WebArchive and manually editing scripts' WebResourceData to insert `debugger;` statements: webarchive-vim is a python script I wrote to streamline this.

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.webkit.org/pipermail/webkit-unassigned/attachments/20150409/65a2acb4/attachment.html>