835873 - Misalignment (incorrect baseline?) when using min-height compared to height

Status: RESOLVED FIXED

(Core :: Layout: Form Controls, defect)

Description

[Mounir Lamouri (:mounir)]

Attachment: Testcase

Two buttons, one with height: 50px and the other with min-height: 50px have the same height as expected but have a different baseline.

Comment 1

[Mounir Lamouri (:mounir)]

The test case and the issue are coming from:
http://stackoverflow.com/questions/14587372/misplacement-of-submit-type-input-in-firefox-when-using-min-height

Comment 2

[Boris Zbarsky [:bzbarsky]]

This happens because the "center child vertically" bit in ReflowButtonContents happens before we adjust the height to take min-height into account (in Reflow).  We should probably pass in the info needed to compute the right thing to ReflowButtonContents or something.

Mounir, want to fix?

Comment 3

[Jeremy Heintz]

Hi, I'm new to bugzilla and would like to fix my first bug! Would this be a good one to start on? Thanks!

Comment 4

[Boris Zbarsky [:bzbarsky]]

This one is fine, yes.  Someone was looking at it at some point, but I haven't heard back from them in a while....

Comment 5

[Boris Zbarsky [:bzbarsky]]

So to expand on comment 2, the way button reflow works right now is that we call ReflowButtonContents to reflow its contents, then set the height of the button based on the size of the contents (unless it has a non-auto height), then adjust the height based on min/max-height.

The problem is that the vertical positioning of the button contents happens inside ReflowButtonContents, and uses the height available to it, which is the intrinsic height of the button unless a non-auto height is specified.

But we already pass aReflowState to ReflowButtonContents, an it already writes to aDesiredSize.height.  So the right thing is probably to move the application of min/max height (the entire block at http://hg.mozilla.org/mozilla-central/file/962f5293f87f/layout/forms/nsHTMLButtonControlFrame.cpp#l213 ) down into ReflowButtonContents, somewhere between the ReflowChild call (which computes the height of the child) and the "center child vertically" bit.

Comment 6

[Usurelu Catalin]

Hi, can I take this bug ?

Comment 7

[Boris Zbarsky [:bzbarsky]]

Sure!

Comment 8

[Josh Matthews [:jdm]]

Usurelu, could you confirm that you're still working on this?

Comment 9

[Usurelu Catalin]

Hi Josh, yes I am, I've run into some problems and I just can't see why it isn't working; now I'm a little busy, if I don't finish it by next week I'll leave it :( .

Comment 10

[Boris Zbarsky [:bzbarsky]]

Please feel free to post what you have in the bug and ask me to look it over to see if anything jumps out at me.  That's why I'm here!

Comment 11

[Usurelu Catalin]

Hi, I'm sorry but I won't be able to work on this bug for some time, please unassign me. Sorry :(

Comment 12

[Boris Zbarsky [:bzbarsky]]

Not a problem.  Just let me know when you have time again!

Comment 13

[betravis]

Attachment: Initial patch

An initial patch based on bz's suggestion in comment 5 to move the aDesiredSize height calculation into ReflowButtonContents.

Comment 14

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

Comment on attachment 772365 [details] [diff] [review]
Initial patch

You definitely need to add the reftest to the reftest.list file so that it will be run.

Comment 15

[betravis]

Attachment: Updated patch

Adding the test to the reftest.list file

Comment 16

[betravis]

Attachment: Updating reftest

The reftests for forms were recently refactored into separate files. The updated patch takes this into account and moves the reftest to the layout/reftests/forms/button directory.

Comment 17

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

Pushed attachment 772740 [details] [diff] [review] to try:
https://tbpl.mozilla.org/?tree=Try&rev=6cfc37da5696

Comment 18

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 772740 [details] [diff] [review]
Updating reftest

You probably want to change the "If computed use the computed value" comment to say something like "Compute our desired height before we start vertically centering our kids".

And please add the missing newlines to the end of your test files.

r=me with those changes.  Thank you for fixing this!

Comment 19

[betravis]

Attachment: Incorporating review feedback

Thanks for the review!

Added newlines to the test files, fixed the comment in nsHTMLButtonControlFrame.cpp, and shortened the log comment.

Comment 20

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/6064e0c9f89e

Comment 21

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/6064e0c9f89e