From 41d59c3b89494c16e2dfa83bb9b5cf831eed2f5b Mon Sep 17 00:00:00 2001
From: Xubin Ren <xubinrencs@gmail.com>
Date: Tue, 17 Mar 2026 08:40:39 +0000
Subject: [PATCH] test(feishu): cover heading and table markdown rendering

---
 nanobot/channels/feishu.py              | 13 +++---
 tests/test_feishu_markdown_rendering.py | 57 +++++++++++++++++++++++++
 2 files changed, 63 insertions(+), 7 deletions(-)
 create mode 100644 tests/test_feishu_markdown_rendering.py

diff --git a/nanobot/channels/feishu.py b/nanobot/channels/feishu.py
index bbe5281..d450e25 100644
--- a/nanobot/channels/feishu.py
+++ b/nanobot/channels/feishu.py
@@ -437,8 +437,10 @@ class FeishuChannel(BaseChannel):
 
     _CODE_BLOCK_RE = re.compile(r"(```[\s\S]*?```)", re.MULTILINE)
 
-    # Markdown bold/italic patterns that need to be stripped for table cells
+    # Markdown formatting patterns that should be stripped from plain-text
+    # surfaces like table cells and heading text.
     _MD_BOLD_RE = re.compile(r"\*\*(.+?)\*\*")
+    _MD_BOLD_UNDERSCORE_RE = re.compile(r"__(.+?)__")
     _MD_ITALIC_RE = re.compile(r"(?<!\*)\*(?!\*)(.+?)(?<!\*)\*(?!\*)")
     _MD_STRIKE_RE = re.compile(r"~~(.+?)~~")
 
@@ -451,6 +453,7 @@ class FeishuChannel(BaseChannel):
         """
         # Remove bold markers
         text = cls._MD_BOLD_RE.sub(r"\1", text)
+        text = cls._MD_BOLD_UNDERSCORE_RE.sub(r"\1", text)
         # Remove italic markers
         text = cls._MD_ITALIC_RE.sub(r"\1", text)
         # Remove strikethrough markers
@@ -532,12 +535,8 @@ class FeishuChannel(BaseChannel):
             before = protected[last_end:m.start()].strip()
             if before:
                 elements.append({"tag": "markdown", "content": before})
-            text = m.group(2).strip()
-            # Avoid double bold markers if text already contains them
-            if text.startswith("**") and text.endswith("**"):
-                display_text = text
-            else:
-                display_text = f"**{text}**"
+            text = self._strip_md_formatting(m.group(2).strip())
+            display_text = f"**{text}**" if text else ""
             elements.append({
                 "tag": "div",
                 "text": {
diff --git a/tests/test_feishu_markdown_rendering.py b/tests/test_feishu_markdown_rendering.py
new file mode 100644
index 0000000..6812a21
--- /dev/null
+++ b/tests/test_feishu_markdown_rendering.py
@@ -0,0 +1,57 @@
+from nanobot.channels.feishu import FeishuChannel
+
+
+def test_parse_md_table_strips_markdown_formatting_in_headers_and_cells() -> None:
+    table = FeishuChannel._parse_md_table(
+        """
+| **Name** | __Status__ | *Notes* | ~~State~~ |
+| --- | --- | --- | --- |
+| **Alice** | __Ready__ | *Fast* | ~~Old~~ |
+"""
+    )
+
+    assert table is not None
+    assert [col["display_name"] for col in table["columns"]] == [
+        "Name",
+        "Status",
+        "Notes",
+        "State",
+    ]
+    assert table["rows"] == [
+        {"c0": "Alice", "c1": "Ready", "c2": "Fast", "c3": "Old"}
+    ]
+
+
+def test_split_headings_strips_embedded_markdown_before_bolding() -> None:
+    channel = FeishuChannel.__new__(FeishuChannel)
+
+    elements = channel._split_headings("# **Important** *status* ~~update~~")
+
+    assert elements == [
+        {
+            "tag": "div",
+            "text": {
+                "tag": "lark_md",
+                "content": "**Important status update**",
+            },
+        }
+    ]
+
+
+def test_split_headings_keeps_markdown_body_and_code_blocks_intact() -> None:
+    channel = FeishuChannel.__new__(FeishuChannel)
+
+    elements = channel._split_headings(
+        "# **Heading**\n\nBody with **bold** text.\n\n```python\nprint('hi')\n```"
+    )
+
+    assert elements[0] == {
+        "tag": "div",
+        "text": {
+            "tag": "lark_md",
+            "content": "**Heading**",
+        },
+    }
+    assert elements[1]["tag"] == "markdown"
+    assert "Body with **bold** text." in elements[1]["content"]
+    assert "```python\nprint('hi')\n```" in elements[1]["content"]