Add missing setmetatable call in set_metatable_gc()

gateway/src/apicast/gc.lua

@@ -4,13 +4,15 @@
 
 local rawgetmetatable = debug.getmetatable
 local getmetatable = getmetatable
+local setmetatable = setmetatable
 local newproxy = newproxy
 local ipairs = ipairs
 local pairs = pairs
 local pcall = pcall
 local table = table
 local unpack = unpack
 local error = error
+local tostring = tostring
 
 local _M = {}
 
@@ -26,31 +28,21 @@ local function __gc(proxy)
 end
 
 local function __tostring(proxy)
-  local mt = getmetatable(proxy)
-
-  if mt and mt.__tostring then
-    return mt.__tostring()
-  end
+  return tostring(original_table(proxy))
 end
 
 local function __call(proxy, ...)
   local t = original_table(proxy)
 
-  local mt = getmetatable(proxy)
-
   -- Try to run __call() and if it's not possible, try to run it in a way that
   -- it returns a meaningful error.
-  if mt and mt.__call then
-    return mt.__call(t, ...)
+  local ret = { pcall(t, ...) }
+  local ok = table.remove(ret, 1)
+
+  if ok then
+    return unpack(ret)
   else
-    local ret = { pcall(t, t, ...) }
-    local ok = table.remove(ret, 1)
-
-    if ok then
-      return unpack(ret)
-    else
-      error(ret[1], 2)
-    end
+    error(ret[1], 2)
   end
 end
 
@@ -71,6 +63,8 @@ end
 -- @tparam table metatable A table that will be used as a metatable. It needs
 --  to define __gc.
 function _M.set_metatable_gc(t, metatable)
+  setmetatable(t, metatable)
+
   -- newproxy() returns a userdata instance
   local proxy = newproxy(true)
 

spec/gc_spec.lua

@@ -44,7 +44,7 @@ describe('GC', function()
       assert.same({ 1, 2, 3 }, res)
     end)
 
-    it('returns an object that respons to pairs', function()
+    it('returns an object that responds to pairs', function()
       local test_table = { 1, 2, 3, some_key = 'some_val' }
       local test_metatable = { __gc = function() end }
 
@@ -58,7 +58,7 @@ describe('GC', function()
       assert.same({ [1] = 1, [2] = 2, [3] = 3, some_key = 'some_val' }, res)
     end)
 
-    it('returns an object that respects the __call in the mt of the original table', function()
+    it('returns an object that respects the __call in the mt passed in the params', function()
       local test_table = { 1, 2, 3 }
       local test_metatable = {
         __gc = function() end,
@@ -78,7 +78,7 @@ describe('GC', function()
       assert.equals(3, table_with_gc(1, 2))
     end)
 
-    it('returns an object that respects the __tostring in the mt of the original table', function()
+    it('returns an object that respects the __tostring in the mt passed in the params', function()
       local test_table = { 1, 2, 3 }
       local test_metatable = {
         __gc = function() end,
@@ -112,5 +112,16 @@ describe('GC', function()
 
       assert.same(test_metatable, getmetatable(table_with_gc))
     end)
+
+    it('returns an object that respects the __index in the mt passed in the params', function()
+      local test_table = { 1, 2, 3 }
+      local test_metatable = {
+        __gc = function() end,
+        __index = { some_func = function() return 'abc' end }
+      }
+      local table_with_gc = GC.set_metatable_gc(test_table, test_metatable)
+
+      assert.equals('abc', table_with_gc:some_func())
+    end)
   end)
 end)