Adds support for grid items with fixed size paddings. Supporting
percentage paddings will probably require to do second pass of tracks
layout: second pass is needed to recalculate tracks sizes when final
items sizes are known when percentage paddings are already resolved.
This change addresses the incorrect assumption that the available width
inside a grid item is equal to the width of the track it belongs to.
For instance, if a grid item has a width of 200px, the available width
inside that item is also 200px regardless of its column(s) base size.
To solve this issue, it was necessary to move the final resolution of
grid items to occur immediately after the final column track sizes are
determined. By doing so, it becomes possible to obtain correct
available width inside grid items while resolving the row track sizes.
This change makes grid items be responsible for their borders instead
of grid tracks which can not have borders itself.
There are changes in layout tests but those are improvements :)
item_incurred_increase should be reset before every next distirbution
because otherwise it will accumulate increases from previous
distributions which is not supposed to happen.
When a width/height constraint is applied to GFC it should set its own
width/height to the sum of track sizes according to the spec.
Changes in layout tests are improvement over what we had before.
Previously, the width and height of grid items were set to match the
size of the grid area they belonged to. With this change, if a grid
item has preferred width or height specified to not "auto" value it
will be resolved using grid area as containing block and used instead.
1. Stop using -1 to indicate infinity value of growth limit. Just use
INFINITY for that.
2. More complete implementation of "Expand Flexible Tracks" step.
3. Return AvailableSize from get_free_space: spec says that this
function can return indefinite size and it is ok.
The file gap.html, which previously had multiple grid tests, has now
been divided into smaller files, each containing only one grid test.
It is going to make it easier to identify what inputs have been
affected by changes in layout code.
The file template-areas.html, which previously had multiple grid tests,
has now been divided into smaller files, each containing only one grid
test. It is going to make it easier to identify what inputs have been
affected by changes in layout code.
Also this change removes parts of template-areas.html that we can't
layout correctly yet.
Although the algorithm for sizing tracks (rows or columns) is defined
once for both dimensions in the specification
(https://www.w3.org/TR/css-grid-2/#algo-track-sizing), we have
implemented it twice separately for sizing rows and columns.
In addition to code duplication, another issue is that these
implementations of the same algorithm have already diverged in some
places, and this divergence is likely to become even worse as our
implementation evolves.
This change unifies code for both dimension into one method that runs
track sizing.
While this change brings a bit of collateral damange (border.html and
minmax.html got changes in layout snaphots) it ultimately brings more
benefits because now we can evolve layout for both rows and colums
without duplicating the code :)
This patch does three things:
- Factors out the code that determines whether a box will create a new
formatting context for its children (and which type of context)
- Uses that code to mark all formatting context roots in layout tree
dumps. This makes it much easier to follow along with layout since
you can now see exactly where control is transferred to a new
formatting context.
- Rebaselines all existing layout tests, since the output format has
changed slightly.
This fixes a bug that was seen when a combination of the grid having
been floated with `float: left` and a `minmax()` column size were used.
The issue was that a grid track size should be considered intrinsically
sized if both the min and max sizes are intrinsic, not just one of them.
VALUES-4 defines the internal representation of `calc()` as a tree of
calculation nodes. ( https://www.w3.org/TR/css-values-4/#calc-internal )
VALUES-3 lacked any definition here, so we had our own ad-hoc
implementation based around the spec grammar. This commit replaces that
with CalculationNodes representing each possible node in the tree.
There are no intended functional changes, though we do now support
nested calc() which previously did not work. For example:
`width: calc( 42 * calc(3 + 7) );`
I have added an example of this to our test page.
A couple of the layout tests that used `calc()` now return values that
are 0.5px different from before. There's no visual difference, so I
have updated the tests to use the new results.
