Bug 140359 - Text reflows when selected on particular page
Summary: Text reflows when selected on particular page
Status: RESOLVED CONFIGURATION CHANGED
Alias: None
Product: WebKit
Classification: Unclassified
Component: Layout and Rendering (show other bugs)
Version: 528+ (Nightly build)
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: zalan
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2015-01-12 08:28 PST by Myles C. Maxfield
Modified: 2021-09-13 18:00 PDT (History)
1 user (show)

See Also:

Attachments
Webarchive (4.61 MB, application/x-webarchive)
2015-01-12 08:28 PST, Myles C. Maxfield 		no flags Details
Test reduction. (414 bytes, text/html)
2015-01-12 10:01 PST, zalan 		no flags Details
Test reduction. (259 bytes, text/html)
2015-01-12 20:31 PST, zalan 		no flags Details
Show Obsolete (1) View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description Myles C. Maxfield 2015-01-12 08:28:39 PST 
Created attachment 244446 [details]
Webarchive

http://9to5mac.com/2015/01/12/iphone-separation-study/
Webarchive attached.

Select "The results showed an increase in blood pressure, indicative of stress or anxiety;"

Version 8.0.2 (10600.2.5, r178109)

Window is fullscreen on a 15" rMBP
Comment 1 zalan 2015-01-12 10:01:19 PST 
Created attachment 244450 [details]
Test reduction.

This has something to do with computing the available space when float is present.
Comment 2 zalan 2015-01-12 20:31:50 PST 
Created attachment 244492 [details]
Test reduction.

New test reduction without float.
Comment 3 zalan 2015-01-12 20:46:50 PST 
(In reply to comment #2)
> Created attachment 244492 [details]
> Test reduction.
> 
> New test reduction without float.

It seems to be a float precision issue. 
1. Complex line layout measures text fragments with leading whitespace, while simple line layout measures them without. (while this could result in mismatching line width due to kerning, this is not the case here.)
2. While adding up the text fragments (without the leading whitespace) + the constant whitespace width, we measure the text as 358.0000025px.
3. Complex line layout measures the fragments as 358px.  
Individually each character measures the same width both cases.
Comment 4 zalan 2021-09-13 18:00:38 PDT 
Works on ToT (r282369).