Split `show` into `realize` and `finalize`

3 files changed, 57 insertions, 87 deletions

diff --git a/src/library/structure/heading.rs b/src/library/structure/heading.rs
index a352cc92..a6c87912 100644
--- a/src/library/structure/heading.rs
+++ b/src/library/structure/heading.rs
@@ -63,11 +63,15 @@ impl Show for HeadingNode {
         }
     }
 
-    fn show(
+    fn realize(&self, _: &mut Context, _: StyleChain) -> TypResult<Content> {
+        Ok(self.body.clone())
+    }
+
+    fn finalize(
         &self,
         ctx: &mut Context,
         styles: StyleChain,
-        realized: Option<Content>,
+        mut realized: Content,
     ) -> TypResult<Content> {
         macro_rules! resolve {
             ($key:expr) => {
@@ -75,8 +79,6 @@ impl Show for HeadingNode {
             };
         }
 
-        let mut body = realized.unwrap_or_else(|| self.body.clone());
-
         let mut map = StyleMap::new();
         map.set(TextNode::SIZE, resolve!(Self::SIZE));
 
@@ -96,30 +98,22 @@ impl Show for HeadingNode {
             map.set(TextNode::EMPH, Toggle);
         }
 
-        let mut seq = vec![];
         if resolve!(Self::UNDERLINE) {
-            body = body.underlined();
-        }
-
-        let above = resolve!(Self::ABOVE);
-        if !above.is_zero() {
-            seq.push(Content::Vertical(above.resolve(styles).into()));
+            realized = realized.underlined();
         }
 
-        seq.push(body);
-
-        let below = resolve!(Self::BELOW);
-        if !below.is_zero() {
-            seq.push(Content::Vertical(below.resolve(styles).into()));
-        }
-
-        let mut content = Content::sequence(seq).styled_with_map(map);
+        realized = realized.styled_with_map(map);
 
         if resolve!(Self::BLOCK) {
-            content = Content::block(content);
+            realized = Content::block(realized);
         }
 
-        Ok(content)
+        realized = realized.spaced(
+            resolve!(Self::ABOVE).resolve(styles),
+            resolve!(Self::BELOW).resolve(styles),
+        );
+
+        Ok(realized)
     }
 }
 
diff --git a/src/library/structure/list.rs b/src/library/structure/list.rs
index c59b443d..6655175f 100644
--- a/src/library/structure/list.rs
+++ b/src/library/structure/list.rs
@@ -79,66 +79,51 @@ impl<const L: ListKind> Show for ListNode<L> {
         }
     }
 
-    fn show(
-        &self,
-        ctx: &mut Context,
-        styles: StyleChain,
-        realized: Option<Content>,
-    ) -> TypResult<Content> {
-        let content = if let Some(content) = realized {
-            content
-        } else {
-            let mut cells = vec![];
-            let mut number = self.start;
-
-            let label = styles.get(Self::LABEL);
-
-            for item in &self.items {
-                number = item.number.unwrap_or(number);
-                cells.push(LayoutNode::default());
-                cells.push(label.resolve(ctx, L, number)?.pack());
-                cells.push(LayoutNode::default());
-                cells.push((*item.body).clone().pack());
-                number += 1;
-            }
-
-            let leading = styles.get(ParNode::LEADING);
-            let spacing = if self.tight {
-                styles.get(Self::SPACING)
-            } else {
-                styles.get(ParNode::SPACING)
-            };
-
-            let gutter = leading + spacing;
-            let indent = styles.get(Self::INDENT);
-            let body_indent = styles.get(Self::BODY_INDENT);
-
-            Content::block(GridNode {
-                tracks: Spec::with_x(vec![
-                    TrackSizing::Relative(indent.into()),
-                    TrackSizing::Auto,
-                    TrackSizing::Relative(body_indent.into()),
-                    TrackSizing::Auto,
-                ]),
-                gutter: Spec::with_y(vec![TrackSizing::Relative(gutter.into())]),
-                cells,
-            })
-        };
-
-        let mut seq = vec![];
-        let above = styles.get(Self::ABOVE);
-        if !above.is_zero() {
-            seq.push(Content::Vertical(above.into()));
+    fn realize(&self, ctx: &mut Context, styles: StyleChain) -> TypResult<Content> {
+        let mut cells = vec![];
+        let mut number = self.start;
+
+        let label = styles.get(Self::LABEL);
+
+        for item in &self.items {
+            number = item.number.unwrap_or(number);
+            cells.push(LayoutNode::default());
+            cells.push(label.resolve(ctx, L, number)?.pack());
+            cells.push(LayoutNode::default());
+            cells.push((*item.body).clone().pack());
+            number += 1;
         }
 
-        seq.push(content);
+        let leading = styles.get(ParNode::LEADING);
+        let spacing = if self.tight {
+            styles.get(Self::SPACING)
+        } else {
+            styles.get(ParNode::SPACING)
+        };
 
-        let below = styles.get(Self::BELOW);
-        if !below.is_zero() {
-            seq.push(Content::Vertical(below.into()));
-        }
+        let gutter = leading + spacing;
+        let indent = styles.get(Self::INDENT);
+        let body_indent = styles.get(Self::BODY_INDENT);
+
+        Ok(Content::block(GridNode {
+            tracks: Spec::with_x(vec![
+                TrackSizing::Relative(indent.into()),
+                TrackSizing::Auto,
+                TrackSizing::Relative(body_indent.into()),
+                TrackSizing::Auto,
+            ]),
+            gutter: Spec::with_y(vec![TrackSizing::Relative(gutter.into())]),
+            cells,
+        }))
+    }
 
-        Ok(Content::sequence(seq))
+    fn finalize(
+        &self,
+        _: &mut Context,
+        styles: StyleChain,
+        realized: Content,
+    ) -> TypResult<Content> {
+        Ok(realized.spaced(styles.get(Self::ABOVE), styles.get(Self::BELOW)))
     }
 }
 
diff --git a/src/library/structure/table.rs b/src/library/structure/table.rs
index aefd01b5..191d3dd3 100644
--- a/src/library/structure/table.rs
+++ b/src/library/structure/table.rs
@@ -64,16 +64,7 @@ impl Show for TableNode {
         }
     }
 
-    fn show(
-        &self,
-        _: &mut Context,
-        styles: StyleChain,
-        realized: Option<Content>,
-    ) -> TypResult<Content> {
-        if let Some(content) = realized {
-            return Ok(content);
-        }
-
+    fn realize(&self, _: &mut Context, styles: StyleChain) -> TypResult<Content> {
         let primary = styles.get(Self::PRIMARY);
         let secondary = styles.get(Self::SECONDARY);
         let stroke = styles.get(Self::STROKE).map(RawStroke::unwrap_or_default);