Fixed layout flow tree JSON serialization
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The second argument for the `emit_struct()` is the number of fields, if given `0`, the output JSON will always be empty.
This is used in `./mach run -d -Z trace-layout https://servo.org`, which will dump the layout flow tree into a `layout_trace.json` file for debugging.
This also unblocks https://github.com/servo/servo/issues/12675
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Implement flexible box layout for row container
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This pull requests implements basic flexible box layout for row container.
It has implemented most basic flexbox features, including grow, shrink, multi-line, *reverse properties, and alignment under `justify-content`, `align-items`, `align-self`, `align-content`.
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r? @pcwalton
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Let textarea wrap lines
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1. Change textarea's style from white-space: pre to white-space: pre-wrap.
2. Display insertion point when a line is wrapped.
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- [X] These changes fix#10053 (github issue number if applicable).
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The 'box_sizing_boundary()' method return the border_padding width in
certain direction if fragment has property 'box-sizing: border-box'. The
'border_padding' field should be initialized before.
This was making us fall in a loop where the start split was empty, but we didn't
ignore it because the current fragment had this flag, but then we treated it
differently depending on the white_space property.
Not totally sure this is the proper fix, but it makes sense to me. In case it
is:
Fixes#12369.
The display list item for a line of text has a single color assigned for
it, so text fragments with different colors cannot be merged.
There is no issue number for this, as far as I know. I found this while
trying an internal program that uses red asterisks for required text
fields.
Fragment debug_id u16 only exists in debug, prod will format mem address
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Each fragment has a `u16` `debug_id` in debug mode, but no `debug_id` in production to save memory. To format a debug id in production, the address of the empty `debug_id` is displayed.
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Do not create stacking contexts for text fragments
Without this change, each text fragment in a block that establishes a
stacking context will establish its own stacking context. This is
unnecessary and increases the amount of work done during display list
construction. This change should not change output, but should improve
performance.
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Without this change, each text fragment in a block that establishes a
stacking context will establish its own stacking context. This is
unnecessary and increases the amount of work done during display list
construction.
WebRender.
This happens asynchronously, just as it does in non-WebRender mode.
This functionality is a prerequisite for doing proper display-list-based
hit testing in WebRender, since it moves the scroll offsets into Servo
(and, specifically, into the script thread, enabling iframe event
forwarding) instead of keeping them private to WebRender.
Requires servo/webrender_traits#55 and servo/webrender#277.
Partially addresses #11108.
The whitespace range was not properly shifted which caused us to adjust the fragment's inline size by the advance of a different set of characters.
This was causing justified text lines to be too long or too short.
LineBreaker calls Fragment::strip_trailing_whitespace_if_necessary and then
recalculates the fragment's inline size. But this isn't necessary because
strip_trailing_whitespace_if_necessary already recalculates the size.
This makes the line breaker determine the final block positions of each
line rather than doing it in a separate pass afterward. Not only does
this simplify the code, it makes `vertical-align` and float placement
interact properly.
Replace character indices with UTF-8 byte offsets throughout the code dealing
with text shaping and breaking. This eliminates a lot of complexity when
converting from one to the other, and interoperates better with the rest of
the Rust ecosystem.
