more tight list improvements

Author: cscheid

crates/quarto-markdown-pandoc/CLAUDE.md

@@ -60,3 +60,5 @@ The `quarto-markdown-pandoc` binary accepts the following options:
 - If you need to fix parser bugs, you will find use in running the application with "-v", which will provide a large amount of information from the tree-sitter parsing process, including a print of the concrete syntax tree out to stderr.
 - use "cargo run --" instead of trying to find the binary location, which will often be outside of this crate.
 - If you need to fix parser bugs, you will find use in running the application with "-v", which will provide a large amount of information from the tree-sitter parsing process, including a print of the concrete syntax tree out to stderr.
+- When fixing inconsistency bugs, use `pandoc -t json -i <input_file>` to get Pandoc's output, and `cargo run -- -t json -i <input_file>` to get our output.
+- When fixing roundtripping bugs, make sure to always add a roundtripping test to `tests/roundtrip_tests/qmd-json-qmd`.

crates/quarto-markdown-pandoc/src/pandoc/treesitter.rs

@@ -1355,6 +1355,11 @@ fn process_list(
                 // if the first block is not a paragraph, it's not loose
                 last_para_range = None;
             }
+        } else {
+            // if the item has multiple blocks (but not multiple paragraphs,
+            // which would have been caught above), we need to reset the
+            // last_para_range since this item can't participate in loose detection
+            last_para_range = None;
         }
         list_items.push(blocks);
     }

crates/quarto-markdown-pandoc/src/writers/qmd.rs

@@ -317,8 +317,8 @@ fn write_bulletlist(bulletlist: &BulletList, buf: &mut dyn std::io::Write) -> st
         }
         let mut item_writer = BulletListContext::new(buf);
         for (j, block) in item.iter().enumerate() {
-            if j > 0 {
-                // Add a blank line between blocks within a list item
+            if j > 0 && !is_tight {
+                // Add a blank line between blocks within a list item in loose lists
                 writeln!(&mut item_writer)?;
             }
             write_block(block, &mut item_writer)?;
@@ -348,8 +348,8 @@ fn write_orderedlist(
         let current_num = start_num + i;
         let mut item_writer = OrderedListContext::new(buf, current_num, delimiter.clone());
         for (j, block) in item.iter().enumerate() {
-            if j > 0 {
-                // Add a blank line between blocks within a list item
+            if j > 0 && !is_tight {
+                // Add a blank line between blocks within a list item in loose lists
                 writeln!(&mut item_writer)?;
             }
             write_block(block, &mut item_writer)?;

crates/quarto-markdown-pandoc/tests/claude-examples/nested-tight-lists-2.qmd

@@ -0,0 +1,4 @@
+* a
+* b
+  * c
+* d

crates/quarto-markdown-pandoc/tests/roundtrip_tests/qmd-json-qmd/nested-tight-lists-2.qmd

@@ -0,0 +1,4 @@
+* a
+* b
+  * c
+* d