[Minor] Lua_util: Rework and add tests for callback_from_string

1 files changed, 30 insertions, 0 deletions

diff --git a/test/lua/unit/lua_util.misc.lua b/test/lua/unit/lua_util.misc.lua
new file mode 100644
index 000000000..b19b4d6f1
--- /dev/null
+++ b/test/lua/unit/lua_util.misc.lua
@@ -0,0 +1,30 @@
+local util  = require 'lua_util'
+
+context("Lua util - callback_from_string", function()
+  local cases = {
+    {'return function', 'return function(a, b) return a + b end'},
+    {'function', 'function(a, b) return a + b end'},
+    {'plain ops', 'local c = select(1, ...)\nreturn c + select(2, ...)'},
+  }
+  local fail_cases = {
+    nil,
+    '',
+    'return function(a, b) ( end',
+    'function(a, b) ( end',
+    'return a + b'
+  }
+
+  for _,c in ipairs(cases) do
+    test('Success case: ' .. c[1], function()
+      local ret,f = util.callback_from_string(c[2])
+      assert_true(ret, f)
+      assert_equal(f(2, 2), 4)
+    end)
+  end
+  for i,c in ipairs(fail_cases) do
+    test('Failure case: ' .. tostring(i), function()
+      local ret,f = util.callback_from_string(c)
+      assert_false(ret)
+    end)
+  end
+end)
\ No newline at end of file