String formatting function tests (#403)

Author: chrisrink10

tests/basilisp/core_macros_test.lpy

@@ -330,6 +330,21 @@
              (:a x)
              (inc x)))))
 
+(deftest with-in-str-test
+  (is (= "Hi I'm a string" (with-in-str "\"Hi I'm a string\"" (read)))))
+
+(deftest with-out-str-test
+  (is (= "Hello, Chris!"
+         (with-out-str
+           (printf "Hello, %s!" "Chris"))))
+  (is (= "Hello, Chris and Rich!"
+         (with-out-str
+           (printf "Hello, %s and %s!" "Chris" "Rich"))))
+  (is (= "Hello, Chris and Rich!"
+         (with-out-str
+           (printf "Hello, %(first)s and %(second)s!"
+                   {"first" "Chris" "second" "Rich"})))))
+
 (deftest fn-sequential-destructuring
   (testing "destructuring first"
     (let [v [:a :b :c :d]

tests/basilisp/core_test.py

@@ -1279,6 +1279,16 @@ def test_shuffle(self, coll):
         assert set(coll) == set(core.shuffle(coll))
 
 
+def test_string_format():
+    assert "Hello, Chris!" == core.format_("Hello, %s!", "Chris")
+    assert "Hello, Chris and Rich!" == core.format_(
+        "Hello, %s and %s!", "Chris", "Rich"
+    )
+    assert "Hello, Chris and Rich!" == core.format_(
+        "Hello, %(first)s and %(second)s!", {"first": "Chris", "second": "Rich"}
+    )
+
+
 def test_merge():
     assert None is core.merge()
     assert lmap.Map.empty() == core.merge(lmap.Map.empty())