From 2bcef2b9ff8bdb28b36a1394698a1d691e8205c4 Mon Sep 17 00:00:00 2001
From: kikito <kikito@gmail.com>
Date: Sat, 2 Jul 2016 06:00:03 +0200
Subject: [PATCH] simplifies isInstanceOf & isSubclassOf. Fixes #39

---
 middleclass.lua               | 12 ++-----
 spec/default_methods_spec.lua | 60 +++++++----------------------------
 2 files changed, 13 insertions(+), 59 deletions(-)

diff --git a/middleclass.lua b/middleclass.lua
index 90fda19..3c15537 100644
--- a/middleclass.lua
+++ b/middleclass.lua
@@ -111,12 +111,7 @@ local DefaultMixin = {
   initialize   = function(self, ...) end,
 
   isInstanceOf = function(self, aClass)
-    return type(self)       == 'table' and
-           type(self.class) == 'table' and
-           type(aClass)     == 'table' and
-           ( aClass == self.class or
-             type(aClass.isSubclassOf) == 'function' and
-             self.class:isSubclassOf(aClass) )
+    return type(aClass) == 'table' and (aClass == self.class or self.class:isSubclassOf(aClass))
   end,
 
   static = {
@@ -153,11 +148,8 @@ local DefaultMixin = {
 
     isSubclassOf = function(self, other)
       return type(other)      == 'table' and
-             type(self)       == 'table' and
              type(self.super) == 'table' and
-             ( self.super == other or
-               type(self.super.isSubclassOf) == 'function' and
-               self.super:isSubclassOf(other) )
+             ( self.super == other or self.super:isSubclassOf(other) )
     end,
 
     include = function(self, ...)
diff --git a/spec/default_methods_spec.lua b/spec/default_methods_spec.lua
index 81602f0..d9a27c6 100644
--- a/spec/default_methods_spec.lua
+++ b/spec/default_methods_spec.lua
@@ -121,36 +121,16 @@ describe('Default methods', function()
 
     describe('isInstanceOf', function()
 
-      describe('nils, integers, strings, tables, and functions', function()
+      describe('primitives', function()
         local o = Object:new()
-        local primitives = {nil, 1, 'hello', {}, function() end}
+        local primitives = {nil, 1, 'hello', {}, function() end, Object:new()}
 
         for _,primitive in pairs(primitives) do
           local theType = type(primitive)
           describe('A ' .. theType, function()
-
-            local f1 = function() return Object.isInstanceOf(primitive, Object) end
-            local f2 = function() return Object.isInstanceOf(primitive, o) end
-            local f3 = function() return Object.isInstanceOf(primitive, primitive) end
-
-            describe('does not throw errors', function()
-              it('instanceOf(Object, '.. theType ..')', function()
-                assert.not_error(f1)
-              end)
-              it('instanceOf(' .. theType .. ', Object:new())', function()
-                assert.not_error(f2)
-              end)
-              it('instanceOf(' .. theType .. ',' .. theType ..')', function()
-                assert.not_error(f3)
-              end)
+            it('object:isInstanceOf(, '.. theType ..') returns false', function()
+              assert.is_false(o:isInstanceOf(primitive))
             end)
-
-            it('makes instanceOf return false', function()
-              assert.is_false(f1())
-              assert.is_false(f2())
-              assert.is_false(f3())
-            end)
-
           end)
         end
 
@@ -196,35 +176,17 @@ describe('Default methods', function()
 
   describe('isSubclassOf', function()
 
-    describe('nils, integers, etc', function()
+    it('returns false for instances', function()
+      assert.is_false(Object:isSubclassOf(Object:new()))
+    end)
+
+    describe('on primitives', function()
       local primitives = {nil, 1, 'hello', {}, function() end}
 
       for _,primitive in pairs(primitives) do
         local theType = type(primitive)
-        describe('A ' .. theType, function()
-
-          local f1 = function() return Object.isSubclassOf(Object, primitive) end
-          local f2 = function() return Object.isSubclassOf(primitive, Object:new()) end
-          local f3 = function() return Object.isSubclassOf(primitive, primitive) end
-
-          describe('does not throw errors', function()
-            it('isSubclassOf(Object, '.. theType ..')', function()
-              assert.not_error(f1)
-            end)
-            it('isSubclassOf(' .. theType .. ', Object:new())', function()
-              assert.not_error(f2)
-            end)
-            it('isSubclassOf(' .. theType .. ',' .. theType ..')', function()
-              assert.not_error(f3)
-            end)
-          end)
-
-          it('makes isSubclassOf return false', function()
-            assert.is_false(f1())
-            assert.is_false(f2())
-            assert.is_false(f3())
-          end)
-
+        it('returns false for ' .. theType, function()
+          assert.is_false(Object:isSubclassOf(primitive))
         end)
       end