12453 - font-weight lighter cycles around

Status: VERIFIED WORKSFORME

(Core :: CSS Parsing and Computation, defect, P3)

Description

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

DESCRIPTION:  If you start at weight 900 and do lighter 9 times (on descendants)
you get a bold font again.  It takes 5 times for weight 500 and only 1 for 100.

STEPS TO REPRODUCE:  Load attached testcase

ACTUAL RESULTS:  Words toward the end of lines become bold.

EXPECTED RESULTS:  Only the word "900" should be bold.

DOES NOT WORK CORRECTLY ON:
 * Linux, viewer, 1999-08-24-08-M9
 * Windows, viewer, 1999-08-24-09-M9

WORKS CORRECTLY ON:
 * Windows IE 4.0

WORKS A DIFFERENT INCORRECT WAY ON:
 * Linux NN 4.6
 * Windows NN 4.6

ADDITIONAL INFORMATION:
lighter shouldn't act like a decrease by 100, and here it seems to be (but if
you look at the other cases in the URL in Daniel Glazman's test suite, it
doesn't act that way!).  Lighter should take one step down among the available
weights - if you're at weight 800 (which acts just like 700), lighter should
take you down to 400 (normal).  This is what happens, which is why this bug
puzzles me so much.

(NN 4.6 does just treat lighter as a step by 100.)

See http://www.w3.org/TR/REC-CSS1#font-weight (and the analogous section of
CSS2, really)

Comment 1

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: test case described in bug.

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

The relevant sections of CSS2 are:
http://www.w3.org/TR/REC-CSS2/fonts.html#propdef-font-weight
http://www.w3.org/TR/REC-CSS2/fonts.html#q46

The fact that the "500" is also bold on Windows (not Linux) is covered by bug
972.

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Once bug 972 is fixed, the EXPECTED RESULTS should read: Every word "lighter"
should be lighter than the word before it, unless the word before it is the
lightest possible, in which case it should be the same as the word before it
(and not bolder).

Comment 4

[troy]

Peter, I think this is style system, too

Comment 5

[Peter Linss]

Pushing off non-beta 1 issues

Comment 6

[Peter Linss]

This needs the font-weight stepping logic in the font code like we discussed.

Comment 7

[Kevin McCluskey (gone)]

Add support for font weights on WIN32.
Previously, all fonts displayed as normal if they where below 400 and as bold if
they were greater .

Now the available fonts are queried and the font weight is selected based on
the algorithm provided in the the CSS2 spec.
Also implemented the CSS1 lighter and bolder logic by looking for the next
available weight.
The weights are queried and cached the first time the font is loaded to avoid
having to query the weights multiple times
for the same font.

Fixed in the Sept 20, 1999, 2:30PM build on WIN32.

Ramiro, reassigning to you for Linux. When working under Linux, please reassign
to dcone for Mac.

Comment 8

[ramiro]

Reassigning to dcone.

dcone: when you are done, reassigning to [e-mail] for the linux work.

Comment 9

[Hixie (not reading bugmail)]

Migrating from {css1} to css1 keyword. The {css1}, {css2}, {css3} and {css-moz}
radars should now be considered deprecated in favour of keywords.
I am *really* sorry about the spam...

Comment 10

[dcone (gone)]

This bug has been marked future because we have determined that it is not 
critical for netscape 6.0.  If you feel this is an error, or if it blocks your 
work in some way -- please attach your concern to the bug for reconsideration.

Comment 11

[timeless]

pavlov, dcone is busy, please look into linux. thanks

Comment 12

[Hixie (not reading bugmail)]

As per meeting with ChrisD yesterday, taking QA.

Comment 13

[Peter Trudelle]

reassigning to erik, cc ftang

Comment 14

[Hixie (not reading bugmail)]

WORKSFORME with:
   Windows 2000 commercial bits 6.0.17.2000010804.
   Some, um, unixy build, labelled 2000073009.

Should be tested on Mac.

Comment 15

[Frank Tang]

Mark work for me , please test Mac

Comment 16

[Hixie (not reading bugmail)]

My Mac is not currently able to run Mozilla usably. Chris, do you have a Mac
you could check this on? If you don't, punt it back to me and I'll find someone
who can check it for me. Thanks.

Comment 17

[Christine Hoffman]

Tested on Mac with 9/12 build. Every span is lighter or the same as the parent. 

Comment 18

[Christine Hoffman]

Additional comments: I am attaching a testcase that expands on David's by 
including font-weights of 100, 200, 300, 400, 500, 600, 700, 800, and 900. In 
this testcase, a default font is used and I am assuming that there are only 2 
font-weights for that font because for each font weight, the first 'lighter' is 
'normal' and remains unchanged. I will verify this bug fixed. Please reopen if 
there are further problems.

Comment 19

[Christine Hoffman]

Attachment: testcase with expanded font-weights

Comment 20

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/284eb932b4f4
[fenix] For https://github.com/mozilla-mobile/fenix/issues/12453 - Sets secure flags on private tab of tabs tray