[types] Move tests to tests/ directory; implement a bunch of Display tests

types/tests/display.rs

@@ -0,0 +1,61 @@
+/* types/tests/display.rs
+ * Eryn Wells <eryn@erynwells.me>
+ */
+
+//! Tests of how various types implement Display.
+
+extern crate sibiltypes;
+
+use sibiltypes::{Obj, Pair, Sym};
+
+
+#[test]
+fn empty_pairs_display_correctly() {
+    let empty = Pair::empty();
+    let disp = format!("{}", empty);
+    assert_eq!(disp, "(())");
+}
+
+#[test]
+fn pair_with_only_car_is_single_element_list() {
+    let sym = Obj::new(Sym::with_str("ab"));
+    let pair = Pair::with_car(sym);
+    let disp = format!("{}", pair);
+    assert_eq!(disp, "(ab)");
+}
+
+#[test]
+fn pair_with_car_and_cdr_is_dotted_pair() {
+    let ab = Obj::new(Sym::with_str("ab"));
+    let cd = Obj::new(Sym::with_str("cd"));
+    let pair = Pair::new(ab, cd);
+    let disp = format!("{}", pair);
+    assert_eq!(disp, "(ab . cd)");
+}
+
+#[test]
+fn two_pair_list_displays_as_list() {
+    let ab = Obj::new(Sym::with_str("ab"));
+    let cd = Obj::new(Sym::with_str("cd"));
+    let pair = Pair::new(ab, Obj::new(Pair::with_car(cd)));
+    let disp = format!("{}", pair);
+    assert_eq!(disp, "(ab cd)");
+}
+
+#[test]
+fn three_element_list_with_full_second_pair() {
+    let ab = Obj::new(Sym::with_str("ab"));
+    let cd = Obj::new(Sym::with_str("cd"));
+    let ef = Obj::new(Sym::with_str("ef"));
+    let pair = Pair::new(ab, Obj::new(Pair::new(cd, ef)));
+    let disp = format!("{}", pair);
+    assert_eq!(disp, "(ab cd . ef)");
+}
+
+#[test]
+fn syms_display_as_strings() {
+    let sym = Sym::with_str("abc");
+    let disp = format!("{}", sym);
+    assert_eq!(disp, "abc");
+}
+