Add test

sqlite_core/src/interaction/buffer.rs

@@ -0,0 +1,33 @@
+use std::sync::{Arc, Mutex};
+
+use crate::interaction::Interaction;
+
+pub struct Buffer {
+    int_buffer: Arc<Mutex<Vec<String>>>,
+    out_buffer: Arc<Mutex<Vec<String>>>,
+}
+
+impl Buffer {
+    pub fn new(int_buffer: Arc<Mutex<Vec<String>>>, out_buffer: Arc<Mutex<Vec<String>>>) -> Self {
+        Self {
+            int_buffer,
+            out_buffer,
+        }
+    }
+}
+
+impl Interaction for Buffer {
+    fn input(&self) -> Result<String, String> {
+        let mut int_buffer = self.int_buffer.lock().unwrap();
+        if let Some(input_string) = int_buffer.pop() {
+            Ok(input_string)
+        } else {
+            Err(String::from("internal_buffer is empty"))
+        }
+    }
+
+    fn output(&self, output: String) {
+        let mut out_buffer = self.out_buffer.lock().unwrap();
+        out_buffer.push(output)
+    }
+}