From 592c76cc29b76c61600c9934dcc8ec2e2a205db1 Mon Sep 17 00:00:00 2001
From: Colin Benner <colin@yzhs.de>
Date: Fri, 28 Sep 2018 00:16:04 +0200
Subject: [PATCH] Test Expr::fmt

---
 src/ast.rs | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/src/ast.rs b/src/ast.rs
index b23b0d2..ec2a837 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -312,3 +312,26 @@ impl fmt::Display for DateToken {
         }
     }
 }
+
+#[cfg(test)]
+mod test {
+    use super::Expr::{self, *};
+
+    fn check<T: ::std::fmt::Display>(e: T, expected: &str) {
+        assert_eq!(format!("{}", e), expected);
+    }
+
+    impl From<i64> for Expr {
+        fn from(x: i64) -> Self {
+            Const(x.into())
+        }
+    }
+
+    #[test]
+    fn test_display_call() {
+        check(Call("f".into(), vec![]), "f()");
+        check(Call("f".into(), vec![1.into()]), "f(1)");
+        check(Call("f".into(), vec![1.into(), 2.into()]), "f(1, 2)");
+        check(Call("f".into(), vec![1.into(), 2.into(), 3.into()]), "f(1, 2, 3)");
+    }
+}