Add unit test for option parsing

src/option_types.cc

@@ -0,0 +1,24 @@
+#include "option_types.hh"
+#include "unit_tests.hh"
+
+namespace Kakoune
+{
+
+UnitTest test_option_parsing{[]{
+    auto check = [](auto&& value, StringView str)
+    {
+        auto repr = option_to_string(value);
+        kak_assert(repr == str);
+        std::decay_t<decltype(value)> parsed;
+        option_from_string(str, parsed);
+        kak_assert(parsed == value);
+    };
+
+    check(123, "123");
+    check(true, "true");
+    check(Vector<String>{"foo", "bar:", "baz"}, "foo:bar\\::baz");
+    check(HashMap<String, int>{{"foo", 10}, {"b=r", 20}, {"b:z", 30}}, "foo=10:b\\=r=20:b\\:z=30");
+    check(DebugFlags::Keys | DebugFlags::Hooks, "hooks|keys");
+}};
+
+}