Fix nested lists

src/lib.rs

@@ -19,7 +19,7 @@ pub fn convert(markdown_text: &str) -> String {
             md::Event::Start(md::Tag::Heading(level)) => state.start_heading(level),
             md::Event::Start(md::Tag::BlockQuote) => state.start_block_quote(),
             md::Event::Start(md::Tag::CodeBlock(_)) => state.start_code_block(),
-            md::Event::Start(md::Tag::List(_)) => (),
+            md::Event::Start(md::Tag::List(_)) => state.start_list(),
             md::Event::Start(md::Tag::Item) => state.start_list_item(),
             md::Event::Start(md::Tag::FootnoteDefinition(_)) => {
                 unimplemented!("footnotes disabled")
@@ -39,7 +39,7 @@ pub fn convert(markdown_text: &str) -> String {
             md::Event::End(md::Tag::BlockQuote) => (),
             md::Event::End(md::Tag::CodeBlock(_)) => state.finish_node(),
             md::Event::End(md::Tag::List(_)) => state.finish_list(),
-            md::Event::End(md::Tag::Item) => state.finish_node(),
+            md::Event::End(md::Tag::Item) => state.finish_item(),
             md::Event::End(md::Tag::FootnoteDefinition(_)) => unimplemented!("footnotes disabled"),
             md::Event::End(md::Tag::Table(_)) => state.finish_table_building(),
             md::Event::End(md::Tag::TableHead) => (),
@@ -118,6 +118,8 @@ struct State {
     link_text_stack: Vec<String>,
     table: Vec<Vec<String>>,
     building_table: bool,
+    nested_list_level: Option<u8>,
+    list_items: Vec<String>,
 }
 
 impl State {
@@ -130,6 +132,8 @@ impl State {
             link_text_stack: vec![],
             table: vec![],
             building_table: false,
+            nested_list_level: None,
+            list_items: vec![],
         }
     }
 
@@ -166,8 +170,16 @@ impl State {
         }
     }
 
+    fn start_list(&mut self) {
+        let level = match self.nested_list_level {
+            Some(n) => n + 1,
+            None => 0,
+        };
+        self.nested_list_level = Some(level);
+    }
+
     fn start_list_item(&mut self) {
-        self.pending_node_type = NodeType::ListItem;
+        self.list_items.push(String::new());
     }
 
     fn toggle_emphasis(&mut self) {
@@ -191,6 +203,12 @@ impl State {
         self.pending_node_content += "[image: ";
     }
 
+    fn finish_item(&mut self) {
+        if self.nested_list_level.is_none() {
+            self.finish_node();
+        }
+    }
+
     fn finish_table_building(&mut self) {
         let mut table = Table::new();
 
@@ -209,14 +227,31 @@ impl State {
     }
 
     fn finish_list(&mut self) {
-        self.nodes.push(vec![]);
+        let level = match self.nested_list_level {
+            Some(0) => {
+                for item in self.list_items.clone() {
+                    self.pending_node_type = NodeType::ListItem;
+                    self.pending_node_content = item;
+                    self.finish_node();
+                }
+                self.list_items.clear();
+                self.force_links();
+                None
+            }
+            Some(n) => Some(n - 1),
+            None => unreachable!("How can you finish a list without level?"),
+        };
+        self.nested_list_level = level;
     }
 
     fn end_link(&mut self, href: &str) {
-        let text = self
-            .link_text_stack
-            .pop()
-            .unwrap_or_else(|| href.to_string());
+        let text = if self.nested_list_level.is_some() {
+            href.to_string()
+        } else {
+            self.link_text_stack
+                .pop()
+                .unwrap_or_else(|| href.to_string())
+        };
         self.pending_other.push(gemtext::Node::Link {
             to: href.to_string(),
             name: Some(text),
@@ -236,6 +271,11 @@ impl State {
         self.pending_node_content += "]";
     }
 
+    fn force_links(&mut self) {
+        let last_cluster = self.nodes.last_mut().expect("empty cluster list??");
+        last_cluster.extend(self.pending_other.drain(..));
+    }
+
     // will create an empty paragraph if pending_text is empty
     fn finish_node(&mut self) {
         match (
@@ -249,13 +289,19 @@ impl State {
         let new_node = self.pending_node_type.take().construct(node_text);
         let last_cluster = self.nodes.last_mut().expect("empty cluster list??");
         last_cluster.push(new_node);
-        last_cluster.extend(self.pending_other.drain(..));
+        if self.nested_list_level.is_none() {
+            last_cluster.extend(self.pending_other.drain(..));
+        }
 
         self.pending_node_content = String::new();
     }
 
     fn add_text(&mut self, text: &str) {
-        if self.building_table {
+        if self.nested_list_level.is_some() {
+            if let Some(last) = self.list_items.last_mut() {
+                last.push_str(text);
+            }
+        } else if self.building_table {
             if let Some(last_row) = self.table.last_mut() {
                 if let Some(last_cell) = last_row.last_mut() {
                     last_cell.push_str(&text.split("<br>").collect::<Vec<&str>>().join("\n"));
@@ -282,6 +328,12 @@ impl State {
                     );
                 }
             }
+        } else if self.nested_list_level.is_some() {
+            if let Some(last) = self.list_items.last_mut() {
+                last.push_str("`");
+                last.push_str(code);
+                last.push_str("`");
+            }
         } else {
             self.pending_node_content += "`";
             self.pending_node_content += code;
@@ -431,3 +483,28 @@ fn test_multi_tables() {
 "#;
     assert_eq!(convert(markdown).trim(), gemtext.trim());
 }
+
+#[cfg(test)]
+#[test]
+fn test_nested_list() {
+    let markdown = r#"
+- item 1
+- item 2
+  - subitem 2.1
+  - subitem [2.2](https://example.com)
+  - subitem [2.3](https://example.com)
+- item 3
+"#;
+
+    let gemtext = r#"
+* item 1
+* item 2
+* subitem 2.1
+* subitem 2.2
+* subitem 2.3
+* item 3
+=> https://example.com https://example.com
+=> https://example.com https://example.com
+"#;
+    assert_eq!(convert(markdown).trim(), gemtext.trim());
+}