fix: handle metamethod for __eq

Fixes #814.

spec/lang/code_gen/macroexp_spec.lua

@@ -144,5 +144,55 @@ describe("macroexp code generation", function()
          print("yes")
       end
    ]]))
+
+   it("can resolve __eq metamethod (regression test for #814)", util.gen([[
+      local type R = record
+         x: number
+         y: number
+
+         metamethod __lt: function(a: R, b: R) = macroexp(a: R, b: R)
+            return a.x < b.x
+         end
+
+         metamethod __eq: function(a: R, b: R) = macroexp(a: R, b: R)
+            return a.x == b.x
+         end
+      end
+
+      local r: R = { x = 10, y = 20 }
+      local s: R = { x = 10, y = 0 }
+
+      if r > s then
+         print("yes")
+      end
+
+      if r == s then
+         print("the 'x' fields are equal")
+      end
+   ]], [[
+
+
+
+
+
+
+
+
+
+
+
+
+
+      local r = { x = 10, y = 20 }
+      local s = { x = 10, y = 0 }
+
+      if s.x < r.x then
+         print("yes")
+      end
+
+      if r.x == s.x then
+         print("the 'x' fields are equal")
+      end
+   ]]))
 end)
 

tl.lua

@@ -12399,9 +12399,9 @@ self:expand_type(node, values, elements) })
             end
 
             if node.op.op == "==" or node.op.op == "~=" then
-
-
-
+               if is_lua_table_type(ra) and is_lua_table_type(rb) then
+                  self:check_metamethod(node, binop_to_metamethod[node.op.op], ra, rb, ua, ub)
+               end
 
                if ra.typename == "enum" and rb.typename == "string" then
                   if not (rb.literal and ra.enumset[rb.literal]) then

tl.tl

@@ -12399,9 +12399,9 @@ do
             end
 
             if node.op.op == "==" or node.op.op == "~=" then
---               if is_lua_table_type(ra) and is_lua_table_type(rb) then
---                  self:check_metamethod(node, binop_to_metamethod[node.op.op], ra, rb)
---               end
+               if is_lua_table_type(ra) and is_lua_table_type(rb) then
+                  self:check_metamethod(node, binop_to_metamethod[node.op.op], ra, rb, ua, ub)
+               end
 
                if ra is EnumType and rb is StringType then
                   if not (rb.literal and ra.enumset[rb.literal]) then