优化: AI Chat全栈多批审查修复与架构清理(risk_level清理/路由解耦/工具渲染/测试补测/死代码)

crates/df-storage/src/migrations.rs

@@ -595,3 +595,65 @@ CREATE TABLE IF NOT EXISTS app_settings (
     updated_at TEXT NOT NULL
 );
 ";
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    // column_exists 是幂等迁移的通用探测辅助(V4+ 全部迁移靠它判断列存在性),
+    // 本组用 in-memory SQLite(:memory:) 建临时表覆盖四种语义:
+    //   列存在→true / 列不存在→false / 表不存在→false / 多列中正确匹配目标列名。
+
+    /// 列存在返回 true:建表后探测真实列名。
+    #[test]
+    fn column_exists_returns_true_for_existing_column() {
+        let conn = Connection::open_in_memory().expect("open in-memory db");
+        conn.execute_batch(
+            "CREATE TABLE probe_t (id TEXT PRIMARY KEY, name TEXT NOT NULL, score INTEGER);",
+        )
+        .expect("create probe table");
+        assert!(column_exists(&conn, "probe_t", "id"));
+        assert!(column_exists(&conn, "probe_t", "name"));
+        assert!(column_exists(&conn, "probe_t", "score"));
+    }
+
+    /// 列不存在返回 false:表存在但目标列名未建。
+    #[test]
+    fn column_exists_returns_false_for_missing_column() {
+        let conn = Connection::open_in_memory().expect("open in-memory db");
+        conn.execute_batch("CREATE TABLE probe_t (id TEXT PRIMARY KEY, name TEXT);")
+            .expect("create probe table");
+        assert!(!column_exists(&conn, "probe_t", "archived"));
+        assert!(!column_exists(&conn, "probe_t", "deleted_at"));
+    }
+
+    /// 表不存在返回 false:PRAGMA table_info 对未知表返回空结果集,函数应安全降级为 false。
+    #[test]
+    fn column_exists_returns_false_when_table_absent() {
+        let conn = Connection::open_in_memory().expect("open in-memory db");
+        // 不建任何表,直接探测
+        assert!(!column_exists(&conn, "ghost_table", "any_col"));
+    }
+
+    /// 多列表中正确匹配目标列名(不误命中前缀/子串):验证精确比较非 contains。
+    #[test]
+    fn column_exists_matches_exact_name_among_many() {
+        let conn = Connection::open_in_memory().expect("open in-memory db");
+        conn.execute_batch(
+            "CREATE TABLE probe_t (
+                id TEXT PRIMARY KEY,
+                prompt_tokens INTEGER,
+                completion_tokens INTEGER,
+                model TEXT
+            );",
+        )
+        .expect("create probe table");
+        // 命中真实列
+        assert!(column_exists(&conn, "probe_t", "prompt_tokens"));
+        assert!(column_exists(&conn, "probe_t", "completion_tokens"));
+        // 不误命中子串(prefix/suffix 近似名)
+        assert!(!column_exists(&conn, "probe_t", "tokens"));
+        assert!(!column_exists(&conn, "probe_t", "prompt"));
+        assert!(!column_exists(&conn, "probe_t", "model_configs"));
+    }
+}