diff --git a/integration_tests/run_tests.py b/integration_tests/run_tests.py
index e563d92434..8f3eb215f6 100755
--- a/integration_tests/run_tests.py
+++ b/integration_tests/run_tests.py
@@ -12,6 +12,7 @@
     "expr_04.py",
     "expr_05.py",
     "test_str_01.py",
+    "test_str_02.py",
     "modules_01.py",
     #"modules_02.py",
     "test_math.py",
diff --git a/integration_tests/test_str_02.py b/integration_tests/test_str_02.py
new file mode 100644
index 0000000000..596ca1ac9f
--- /dev/null
+++ b/integration_tests/test_str_02.py
@@ -0,0 +1,20 @@
+def f():
+    x: str
+    x = "abcdefghijkl"
+    x = x + "123"
+    assert x == "abcdefghijkl123"
+    g(x)
+    y: str
+    y = h(x)
+    print(y)
+    assert y == "abcdefghijkl123|x"
+
+def g(x: str):
+    print(x)
+    assert x == "abcdefghijkl123"
+
+def h(x: str) -> str:
+    return x + "|x"
+
+
+f()