tests/basics: Add tests for if-expressions.

tests/basics/ifexpr.py

@@ -0,0 +1,9 @@
+# test if-expressions
+
+print(1 if 0 else 2)
+print(3 if 1 else 4)
+
+def f(x):
+    print('a' if x else 'b')
+f([])
+f([1])