Handle paragraph indent at a later stage

library/src/layout/flow.rs

@@ -1,3 +1,5 @@
+use typst::model::{Property, StyleEntry};
+
 use super::{AlignNode, ColbreakNode, PlaceNode, Spacing, VNode};
 use crate::prelude::*;
 use crate::text::ParNode;
@@ -58,6 +60,8 @@ struct FlowLayouter {
     used: Size,
     /// The sum of fractions in the current region.
     fr: Fr,
+    /// Whether the last block was a paragraph.
+    last_block_was_par: bool,
     /// Spacing and layouted blocks.
     items: Vec<FlowItem>,
     /// Finished frames for previous regions.
@@ -92,6 +96,7 @@ impl FlowLayouter {
             full,
             used: Size::zero(),
             fr: Fr::zero(),
+            last_block_was_par: false,
             items: vec![],
             finished: vec![],
         }
@@ -150,8 +155,18 @@ impl FlowLayouter {
                 .unwrap_or(Align::Top),
         );
 
+        // Disable paragraph indent if this is not a consecutive paragraph.
+        let reset;
+        let is_par = block.is::<ParNode>();
+        let mut chained = styles;
+        if !self.last_block_was_par && is_par && !styles.get(ParNode::INDENT).is_zero() {
+            let property = Property::new(ParNode::INDENT, Length::zero());
+            reset = StyleEntry::Property(property);
+            chained = reset.chain(&styles);
+        }
+
         // Layout the block itself.
-        let frames = block.layout_block(world, &self.regions, styles)?;
+        let frames = block.layout_block(world, &self.regions, chained)?;
         let len = frames.len();
         for (i, frame) in frames.into_iter().enumerate() {
             // Grow our size, shrink the region and save the frame for later.
@@ -166,6 +181,8 @@ impl FlowLayouter {
             }
         }
 
+        self.last_block_was_par = is_par;
+
         Ok(())
     }
 

library/src/layout/mod.rs

@@ -474,13 +474,14 @@ struct FlowBuilder<'a>(BehavedBuilder<'a>, bool);
 
 impl<'a> FlowBuilder<'a> {
     fn accept(&mut self, content: &Content, styles: StyleChain<'a>) -> bool {
-        let last_was_parbreak = self.1;
-        self.1 = false;
+        let last_was_parbreak = std::mem::replace(&mut self.1, false);
 
         if content.is::<ParbreakNode>() {
             self.1 = true;
+            return true;
         } else if content.is::<VNode>() || content.is::<ColbreakNode>() {
             self.0.push(content.clone(), styles);
+            return true;
         } else if content.has::<dyn LayoutBlock>() {
             if !last_was_parbreak {
                 let tight = if let Some(node) = content.downcast::<ListNode>() {
@@ -505,11 +506,10 @@ impl<'a> FlowBuilder<'a> {
             self.0.push(above.pack(), styles);
             self.0.push(content.clone(), styles);
             self.0.push(below.pack(), styles);
-        } else {
-            return false;
+            return true;
         }
 
-        true
+        false
     }
 
     fn finish(self, doc: &mut DocBuilder<'a>, styles: StyleChain<'a>) {
@@ -545,39 +545,10 @@ impl<'a> ParBuilder<'a> {
     }
 
     fn finish(self, parent: &mut Builder<'a>) {
-        let (mut children, shared) = self.0.finish();
-        if children.is_empty() {
-            return;
+        let (children, shared) = self.0.finish();
+        if !children.is_empty() {
+            parent.flow.accept(&ParNode(children).pack(), shared);
         }
-
-        // Paragraph indent should only apply if the paragraph starts with
-        // text and follows directly after another paragraph.
-        let indent = shared.get(ParNode::INDENT);
-        if !indent.is_zero()
-            && children
-                .items()
-                .find_map(|child| {
-                    if child.is::<TextNode>() || child.is::<SmartQuoteNode>() {
-                        Some(true)
-                    } else if child.has::<dyn LayoutInline>() {
-                        Some(false)
-                    } else {
-                        None
-                    }
-                })
-                .unwrap_or_default()
-            && parent
-                .flow
-                .0
-                .items()
-                .rev()
-                .find(|child| child.has::<dyn LayoutBlock>())
-                .map_or(false, |child| child.is::<ParNode>())
-        {
-            children.push_front(HNode::strong(indent.into()).pack());
-        }
-
-        parent.flow.accept(&ParNode(children).pack(), shared);
     }
 
     fn is_empty(&self) -> bool {

library/src/text/par.rs

@@ -393,6 +393,26 @@ fn collect<'a>(
     let mut segments = vec![];
     let mut iter = par.0.iter().peekable();
 
+    let indent = styles.get(ParNode::INDENT);
+    if !indent.is_zero()
+        && par
+            .0
+            .items()
+            .find_map(|child| {
+                if child.is::<TextNode>() || child.is::<SmartQuoteNode>() {
+                    Some(true)
+                } else if child.has::<dyn LayoutInline>() {
+                    Some(false)
+                } else {
+                    None
+                }
+            })
+            .unwrap_or_default()
+    {
+        full.push(SPACING_REPLACE);
+        segments.push((Segment::Spacing(indent.into()), *styles));
+    }
+
     while let Some((child, map)) = iter.next() {
         let styles = map.chain(styles);
         let segment = if child.is::<SpaceNode>() {