fix(sessions): surface get_cli_sessions() failures via logger.warning (#769)

Logs warnings instead of silently returning [] on DB errors. Fixes #634.

tests/test_issue634.py

@@ -0,0 +1,75 @@
+"""
+Tests for #634: CLI sessions not visible when setting is enabled.
+
+Root cause: get_cli_sessions() swallowed all errors silently (bare except → return []).
+Users with older hermes-agent versions (missing 'source' column in state.db) got
+an empty list with no log output, making diagnosis impossible.
+
+Fixes:
+1. Schema introspection: check for 'source' column before querying, log a warning
+   if missing and return early.
+2. Exception path: log a warning instead of silently returning [].
+"""
+import pathlib
+import re
+
+MODELS_PY = pathlib.Path(__file__).parent.parent / 'api' / 'models.py'
+src = MODELS_PY.read_text(encoding='utf-8')
+
+
+class TestCliSessionsErrorSurface:
+    """get_cli_sessions() must log warnings instead of silently returning []."""
+
+    def test_schema_introspection_present(self):
+        """The function must check for the 'source' column before querying."""
+        assert "PRAGMA table_info(sessions)" in src
+
+    def test_missing_source_column_logs_warning(self):
+        """If 'source' column is absent, a warning is logged."""
+        # The warning message must mention the missing column and how to fix it
+        assert "no 'source' column" in src or "has no 'source' column" in src
+
+    def test_missing_source_column_suggests_upgrade(self):
+        """Warning message must suggest upgrading hermes-agent."""
+        assert "Upgrade hermes-agent" in src or "upgrade hermes-agent" in src.lower()
+
+    def test_exception_path_logs_warning(self):
+        """The except clause must call logger.warning, not silently pass."""
+        # Find the exception handler in get_cli_sessions
+        func_start = src.find("def get_cli_sessions()")
+        func_end = src.find("\ndef ", func_start + 1)
+        func_body = src[func_start:func_end] if func_end != -1 else src[func_start:]
+        assert "warning(" in func_body, \
+            "get_cli_sessions() exception handler must call logging.warning()"
+
+    def test_exception_path_includes_db_path(self):
+        """The warning must include the db_path for diagnosability."""
+        func_start = src.find("def get_cli_sessions()")
+        func_end = src.find("\ndef ", func_start + 1)
+        func_body = src[func_start:func_end] if func_end != -1 else src[func_start:]
+        # db_path should appear in the warning call
+        warning_pos = func_body.find("warning(")
+        warning_block = func_body[warning_pos:warning_pos + 300]
+        assert "db_path" in warning_block, \
+            "Warning must include db_path so admins can find the problematic database"
+
+    def test_still_returns_empty_on_error(self):
+        """Function must still return [] after logging (graceful degradation)."""
+        # After the warning, it should return cli_sessions (the empty list) not raise
+        func_start = src.find("def get_cli_sessions()")
+        func_end = src.find("\ndef ", func_start + 1)
+        func_body = src[func_start:func_end] if func_end != -1 else src[func_start:]
+        # Must have a 'return' after the warning call
+        warning_pos = func_body.find("_cli_err:")
+        after_warning = func_body[warning_pos:warning_pos + 400]
+        assert "return" in after_warning, \
+            "Function must return after the warning (not raise)"
+
+    def test_source_column_check_before_sql_query(self):
+        """Schema check must happen before the main SQL SELECT."""
+        pragma_pos = src.find("PRAGMA table_info(sessions)")
+        select_pos = src.find("SELECT s.id, s.title, s.model")
+        assert pragma_pos != -1, "PRAGMA check not found"
+        assert select_pos != -1, "SELECT query not found"
+        assert pragma_pos < select_pos, \
+            "Schema introspection must run before the main SQL query"