REPRODUCIBLE ASSERT: range != nil in WebViewFactory.mm:415 -[WebViewFactory startOfTextMarkerRange:]

[David Kilzer (:ddkilzer)]

* SUMMARY
Sequence of steps leads to a reproducible assert in debug builds of WebKit.

* STEPS TO REPRODUCE
1. Open Safari/WebKit.
2. Open URL (or any page with an <input type="text"> in it.
3. Click in the text field.
4. Type text like "asdf".
5. Hit Cmd-A to select all.
6. Type a new word like "Hello".
7. Position mouse pointer over word.
8. Hit Cmd-Ctrl-D to bring up the dictionary/thesaurus.

* EXPECTED RESULTS
The dictionary should be brought up for the word (or at least Safari/WebKit should not crash).

* ACTUAL RESULTS
Safari/WebKit crashes due to an assert.

* REGRESSION
Only tested with Safari 2.0.4 (419.3) on Mac OS X 10.4.9 (8P135) with a local debug build of WebKit r20896.

[David Kilzer (:ddkilzer)]

Lowering from P1 because I don't have the steps to reproduce correct.  (Sometimes it happens, sometimes it doesn't.)

Stack trace:

PID:    10306
Thread: 0

Exception:  EXC_BAD_ACCESS (0x0001)
Codes:      KERN_INVALID_ADDRESS (0x0001) at 0xbbadbeef

Thread 0 Crashed:
0   com.apple.WebKit         	0x0033a1f4 -[WebViewFactory startOfTextMarkerRange:] + 92 (WebViewFactory.mm:415)
1   com.apple.WebCore        	0x0104501c -[WebCoreAXObject visiblePositionForStartOfTextMarkerRange:] + 136 (WebCoreAXObject.mm:941)
2   com.apple.WebCore        	0x0105052c -[WebCoreAXObject doAXAttributedStringForTextMarkerRange:] + 76 (WebCoreAXObject.mm:1630)
3   com.apple.WebCore        	0x01049bf4 -[WebCoreAXObject doAXAttributedStringForRange:] + 128 (WebCoreAXObject.mm:2146)
4   com.apple.WebCore        	0x0104f224 -[WebCoreAXObject doAXRTFForRange:] + 92 (WebCoreAXObject.mm:2153)
5   com.apple.WebCore        	0x0104b11c -[WebCoreAXObject accessibilityAttributeValue:forParameter:] + 5212 (WebCoreAXObject.mm:2316)
6   com.apple.AppKit         	0x93a665fc CopyParameterizedAttributeValue + 240
7   com.apple.HIServices     	0x91871d94 _AXXMIGCopyParameterizedAttributeValue + 312
8   com.apple.HIServices     	0x91879230 _XCopyParameterizedAttributeValue + 288
9   com.apple.HIServices     	0x91844404 mshMIGPerform + 308
10  com.apple.CoreFoundation 	0x907ec764 __CFRunLoopDoSource1 + 152
11  com.apple.CoreFoundation 	0x907dee7c __CFRunLoopRun + 1556
12  com.apple.CoreFoundation 	0x907de4ac CFRunLoopRunSpecific + 268
13  com.apple.HIToolbox      	0x9329bb20 RunCurrentEventLoopInMode + 264
14  com.apple.HIToolbox      	0x9329b1b4 ReceiveNextEventCommon + 380
15  com.apple.HIToolbox      	0x9329b020 BlockUntilNextEventMatchingListInMode + 96
16  com.apple.AppKit         	0x937a1ae4 _DPSNextEvent + 384
17  com.apple.AppKit         	0x937a17a8 -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 116
18  com.apple.Safari         	0x00006740 0x1000 + 22336
19  com.apple.AppKit         	0x9379dcec -[NSApplication run] + 472
20  com.apple.AppKit         	0x9388e87c NSApplicationMain + 452
21  com.apple.Safari         	0x0005c77c 0x1000 + 374652
22  com.apple.Safari         	0x0005c624 0x1000 + 374308

[David Kilzer (:ddkilzer)]

Back to P1--new repeatable steps to reproduce.

* STEPS TO REPRODUCE
1. Open Safari/WebKit.
2. Open URL (or any page with an <input type="text"> in it.
3. Click in the text field.
4. Type text like "asdf".
5. Use Cmd-Tab to switch to another application (so Safari/WebKit loses focus).
6. Hit Cmd-Tab to switch back to Safari/WebKit.  DO NOT CLICK IN ANY SAFARI WINDOW.
7. Position the mouse pointer over "asdf" in the text field.
8. Hit Cmd-Ctrl-D to bring up the dictionary.

At this point, the assert should be hit on a debug build and Safari/WebKit will crash.

[Darin Adler]

<rdar://problem/5153017>

[Eric Seidel (no email)]

Maybe Safari/WebKit makes some assumption about the window having keyfocus.

[Maxime BRITTO]

I can't reproduce it on r22090.

[Oliver Hunt]

Fix was landed r21158