1 files changed, 51 insertions, 0 deletions

diff --git a/test_llamachat.py b/test_llamachat.py
index 0986631..f23a576 100755
--- a/test_llamachat.py
+++ b/test_llamachat.py
@@ -217,6 +217,21 @@ def test_sse_parsing():
     )
     assert opening is None
     assert opening != backend.DONE
+
+    # A delta carrying both fields is thinking, not reply. Classifying it as
+    # content splices the tail of the reasoning onto the front of the reply.
+    both = backend._parse_sse_line(
+        'data: {"choices":[{"delta":'
+        '{"reasoning_content":"still thinking","content":""}}]}'
+    )
+    assert both == ("reasoning", "still thinking"), both
+
+    # An empty reasoning delta renders nothing and must not fall through to
+    # the content branch.
+    empty = backend._parse_sse_line(
+        'data: {"choices":[{"delta":{"reasoning_content":""}}]}'
+    )
+    assert empty is None, empty
     print("ok  sse parsing")
 
 
@@ -365,6 +380,41 @@ def test_markdown_rendering():
     print("ok  markdown rendering")
 
 
+def test_unbalanced_backticks():
+    """An odd backtick cannot reflow the rest of a reply as code."""
+    import os
+
+    os.environ.setdefault("QT_QPA_PLATFORM", "offscreen")
+    from PySide6.QtWidgets import QApplication
+
+    from llamachat.ui import _close_fences, _markdown_to_fragment
+
+    app = QApplication.instance() or QApplication([])
+    assert app is not None
+
+    # An unclosed fence gets one, so the tail is not swallowed.
+    assert _close_fences("a\n```py\nx=1").endswith("\n```")
+    # A closed fence is left exactly as it was.
+    balanced = "a\n```py\nx=1\n```\ntail"
+    assert _close_fences(balanced) == balanced
+    # A longer opener needs a closer at least as long.
+    assert _close_fences("````\nx").endswith("\n````")
+    # Tildes are fences too.
+    assert _close_fences("~~~\nx").endswith("\n~~~")
+    # A lone inline tick is dropped rather than opening a run.
+    assert "`" not in _close_fences("use ` here")
+    # Balanced inline ticks survive untouched.
+    assert _close_fences("a `b` c") == "a `b` c"
+
+    # The real failure: reasoning text full of ticks must not become one
+    # block that eats the prose after it.
+    leaked = "` (wait)\nthen `find / -perm -4000` and more prose here"
+    rendered = _markdown_to_fragment(leaked)
+    assert "more prose here" in rendered
+    assert "<pre" not in rendered, rendered
+    print("ok  unbalanced backticks")
+
+
 def test_system_qt_theme_guard():
     """The plugin path is only borrowed when the Qt versions agree."""
     import os
@@ -864,6 +914,7 @@ if __name__ == "__main__":
     test_session_prompt_storage()
     test_prompt_column_migration()
     test_markdown_rendering()
+    test_unbalanced_backticks()
     test_sidebar_toggle()
     test_shortcuts()
     test_system_qt_theme_guard()