2 files changed, 20 insertions, 3 deletions

diff --git a/xtask/src/codegen.rs b/xtask/src/codegen.rs
index 44729cd57..4ec8ab75a 100644
--- a/xtask/src/codegen.rs
+++ b/xtask/src/codegen.rs
@@ -74,6 +74,14 @@ fn reformat(text: impl std::fmt::Display) -> Result<String> {
 }
 
 fn extract_comment_blocks(text: &str) -> Vec<Vec<String>> {
+    do_extract_comment_blocks(text, false)
+}
+
+fn extract_comment_blocks_with_empty_lines(text: &str) -> Vec<Vec<String>> {
+    do_extract_comment_blocks(text, true)
+}
+
+fn do_extract_comment_blocks(text: &str, allow_blocks_with_empty_lins: bool) -> Vec<Vec<String>> {
     let mut res = Vec::new();
 
     let prefix = "// ";
@@ -81,6 +89,11 @@ fn extract_comment_blocks(text: &str) -> Vec<Vec<String>> {
 
     let mut block = vec![];
     for line in lines {
+        if line == "//" && allow_blocks_with_empty_lins {
+            block.push(String::new());
+            continue;
+        }
+
         let is_comment = line.starts_with(prefix);
         if is_comment {
             block.push(line[prefix.len()..].to_string());
diff --git a/xtask/src/codegen/gen_assists_docs.rs b/xtask/src/codegen/gen_assists_docs.rs
index 654ae09d6..e313820d1 100644
--- a/xtask/src/codegen/gen_assists_docs.rs
+++ b/xtask/src/codegen/gen_assists_docs.rs
@@ -1,7 +1,7 @@
 use std::{fs, path::Path};
 
 use crate::{
-    codegen::{self, extract_comment_blocks, Mode},
+    codegen::{self, extract_comment_blocks_with_empty_lines, Mode},
     project_root, Result,
 };
 
@@ -34,7 +34,7 @@ fn collect_assists() -> Result<Vec<Assist>> {
 
     fn collect_file(acc: &mut Vec<Assist>, path: &Path) -> Result<()> {
         let text = fs::read_to_string(path)?;
-        let comment_blocks = extract_comment_blocks(&text);
+        let comment_blocks = extract_comment_blocks_with_empty_lines(&text);
 
         for block in comment_blocks {
             // FIXME: doesn't support blank lines yet, need to tweak
@@ -45,7 +45,11 @@ fn collect_assists() -> Result<Vec<Assist>> {
                 continue;
             }
             let id = first_line["Assist: ".len()..].to_string();
-            assert!(id.chars().all(|it| it.is_ascii_lowercase() || it == '_'));
+            assert!(
+                id.chars().all(|it| it.is_ascii_lowercase() || it == '_'),
+                "invalid assist id: {:?}",
+                id
+            );
 
             let doc = take_until(lines.by_ref(), "```");
             let before = take_until(lines.by_ref(), "```");