Bug 156566 – JSContext Inspector: Improve Class instances and JSC API Exported Values view in Console / ObjectTree

• Status: RESOLVED
• Resolution: FIXED
• Component: Web Inspector

[Joseph Pecoraro]

* SUMMARY
Improve Class instances and JSC API Exported Values view in Console / ObjectTree

Given this example ObjC Exported class:

    @protocol JSBridgeExports <JSExport>
    @property (readonly) NSUInteger count;
    - (void)log:(NSString *)str;
    - (void)clear;
    - (void)test;
    @end

    @interface JSBridge : NSObject <JSBridgeExports>
    @end

    ... /* implementation */

    _bridge = [[JSBridge alloc] init];    
    JSValue *globalObject = [_context globalObject];
    globalObject[@"bridge"] = _bridge;

Or the same as an ES6 Class instance:

    JSBridge = class JSBridge {
        get count() { return 1; }
        log(str) {}
        clear() {}
        test() {}
    };
    bridge = new JSBridge;

Currently logging this object in the console results in very little:

    js> bridge
    JSBridge {}

There are a couple improvements that can be made here.

All of the properties / methods of these objects are non-enumerable, which is why our UI treats them as lossless.

    1. Any non-basic Object type that has a prototype should be expandable
      - having a non-basic prototype likely means there are methods you can use,
        so treat them as not lossless, to allow expanding to see the methods.

    2. Special Case Native Getters to show in Preview, even if non-enumerable
      - This applies to the JSC API Exported @property getters, which are non-enumerable.
        We skipped non-enumerable properties in previews before.
      - This follows the existing convention we have of invoking getters if they are native
        because we assume they shouldn't have side-effects.
      - This would make the preview "JSBridge {count:#}" for the Exported API object

[Joseph Pecoraro]

<rdar://problem/16392365>

[Joseph Pecoraro]

Created attachment 276370 [details]
[PATCH] Proposed Fix

[WebKit Commit Bot]

Comment on attachment 276370 [details]
[PATCH] Proposed Fix

Clearing flags on attachment: 276370

Committed r199529: <http://trac.webkit.org/changeset/199529>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.