layout: Add a InlineFormattingContextBuilder (#32415)

The main change here is that collapsed and `text-transform`'d text is
computed as it's processed by DOM traversal. This single transformed
text is stored in the root of the `InlineFormattingContext`.

This will eventually allow performing linebreaking and shaping of the
entire inline formatting context at once. Allowing for intelligent
processing of linebreaking and also shaping across elements. This
matches more closely what LayoutNG does.

This shouldn't have any (or negligable) behavioral changes, but will
allow us to prevent linebreaking inside of clusters in a followup
change.

Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>

components/layout_2020/flexbox/construct.rs

@@ -12,7 +12,8 @@ use crate::cell::ArcRefCell;
 use crate::context::LayoutContext;
 use crate::dom::{BoxSlot, LayoutBox, NodeExt};
 use crate::dom_traversal::{Contents, NodeAndStyleInfo, NonReplacedContents, TraversalHandler};
-use crate::flow::BlockFormattingContext;
+use crate::flow::inline::construct::InlineFormattingContextBuilder;
+use crate::flow::{BlockContainer, BlockFormattingContext};
 use crate::formatting_contexts::{
     IndependentFormattingContext, NonReplacedFormattingContext,
     NonReplacedFormattingContextContents,
@@ -47,7 +48,7 @@ struct FlexContainerBuilder<'a, 'dom, Node> {
     context: &'a LayoutContext<'a>,
     info: &'a NodeAndStyleInfo<Node>,
     text_decoration_line: TextDecorationLine,
-    contiguous_text_runs: Vec<TextRun<'dom, Node>>,
+    contiguous_text_runs: Vec<FlexTextRun<'dom, Node>>,
     /// To be run in parallel with rayon in `finish`
     jobs: Vec<FlexLevelJob<'dom, Node>>,
     has_text_runs: bool,
@@ -61,10 +62,10 @@ enum FlexLevelJob<'dom, Node> {
         contents: Contents,
         box_slot: BoxSlot<'dom>,
     },
-    TextRuns(Vec<TextRun<'dom, Node>>),
+    TextRuns(Vec<FlexTextRun<'dom, Node>>),
 }
 
-struct TextRun<'dom, Node> {
+struct FlexTextRun<'dom, Node> {
     info: NodeAndStyleInfo<Node>,
     text: Cow<'dom, str>,
 }
@@ -74,7 +75,7 @@ where
     Node: NodeExt<'dom>,
 {
     fn handle_text(&mut self, info: &NodeAndStyleInfo<Node>, text: Cow<'dom, str>) {
-        self.contiguous_text_runs.push(TextRun {
+        self.contiguous_text_runs.push(FlexTextRun {
             info: info.clone(),
             text,
         })
@@ -103,7 +104,7 @@ where
 }
 
 /// <https://drafts.csswg.org/css-text/#white-space>
-fn is_only_document_white_space<Node>(run: &TextRun<'_, Node>) -> bool {
+fn is_only_document_white_space<Node>(run: &FlexTextRun<'_, Node>) -> bool {
     // FIXME: is this the right definition? See
     // https://github.com/w3c/csswg-drafts/issues/5146
     // https://github.com/w3c/csswg-drafts/issues/5147
@@ -146,28 +147,40 @@ where
 
         let mut children = std::mem::take(&mut self.jobs)
             .into_par_iter()
-            .map(|job| match job {
-                FlexLevelJob::TextRuns(runs) => ArcRefCell::new(FlexLevelBox::FlexItem({
-                    let runs = runs.into_iter().map(|run| {
-                        crate::flow::text_run::TextRun::new(
-                            (&run.info).into(),
-                            run.info.style,
-                            run.text.into(),
-                        )
-                    });
-                    let bfc = BlockFormattingContext::construct_for_text_runs(
-                        runs,
+            .filter_map(|job| match job {
+                FlexLevelJob::TextRuns(runs) => {
+                    let mut inline_formatting_context_builder =
+                        InlineFormattingContextBuilder::new();
+                    for flex_text_run in runs.into_iter() {
+                        inline_formatting_context_builder
+                            .push_text(flex_text_run.text, &flex_text_run.info);
+                    }
+
+                    let Some(inline_formatting_context) = inline_formatting_context_builder.finish(
                         self.context,
                         self.text_decoration_line,
+                        true, /* has_first_formatted_line */
+                    ) else {
+                        return None;
+                    };
+
+                    let block_formatting_context = BlockFormattingContext::from_block_container(
+                        BlockContainer::InlineFormattingContext(inline_formatting_context),
                     );
                     let info = &self.info.new_anonymous(anonymous_style.clone().unwrap());
-                    IndependentFormattingContext::NonReplaced(NonReplacedFormattingContext {
+                    let non_replaced = NonReplacedFormattingContext {
                         base_fragment_info: info.into(),
                         style: info.style.clone(),
                         content_sizes: None,
-                        contents: NonReplacedFormattingContextContents::Flow(bfc),
-                    })
-                })),
+                        contents: NonReplacedFormattingContextContents::Flow(
+                            block_formatting_context,
+                        ),
+                    };
+
+                    Some(ArcRefCell::new(FlexLevelBox::FlexItem(
+                        IndependentFormattingContext::NonReplaced(non_replaced),
+                    )))
+                },
                 FlexLevelJob::Element {
                     info,
                     display,
@@ -200,7 +213,7 @@ where
                         ))
                     };
                     box_slot.set(LayoutBox::FlexLevel(box_.clone()));
-                    box_
+                    Some(box_)
                 },
             })
             .collect::<Vec<_>>();