add a simple test

src/twopass.rs

@@ -393,3 +393,40 @@ impl OpenFunction {
 		}
 	}
 }
+
+#[cfg(test)]
+mod tests {
+	use crate::ast::*;
+
+	use super::build;
+
+	#[test]
+	fn test_local() {
+		let testee = Function {
+			name: Some("testee".into()),
+			args: vec![],
+			body: vec![
+				Statement::Assign {
+					target: Location::Variable { name: "x".into() },
+					source: Box::new(Expression::Constant(Constant::Number(1))),
+				},
+				Statement::Local {
+					name: "x".into(),
+					init: Some(Box::new(Expression::Constant(Constant::Number(2)))),
+				},
+				Statement::Assign {
+					target: Location::Variable { name: "x".into() },
+					source: Box::new(Expression::Constant(Constant::Number(3))),
+				},
+			],
+			ret: Some(Box::new(Expression::Variable(Location::Variable {
+				name: "x".into(),
+			}))),
+		};
+		let env = crate::types::Table::default();
+		let testee = build(&testee);
+		let ret = testee.call(Some(env.clone().into()), &[]);
+		assert_eq!(ret, Some(3.into()));
+		assert_eq!(env.get("x".into()), Some(1.into()));
+	}
+}