Fix incorrect assumption in IDMap and SmallMap tests.

base/containers/small_map_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/containers/small_map.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <functional>
@@ skipping 120 matching lines @@
     EXPECT_EQ(m[1234], 90);
     EXPECT_EQ(m[   8], 23);
     EXPECT_EQ(m[  -5],  6);
     EXPECT_EQ(m.size(), 5u);
     EXPECT_FALSE(m.empty());
     EXPECT_TRUE(m.UsingFullMap());
   }
 }
 
 template<class inner>
-static void SmallMapToMap(SmallMap<inner> const& src, inner* dest) {
+static bool SmallMapIsSubset(SmallMap<inner> const& a,
+                             SmallMap<inner> const& b) {
   typename SmallMap<inner>::const_iterator it;
-  for (it = src.begin(); it != src.end(); ++it) {
-    dest->insert(std::make_pair(it->first, it->second));
+  for (it = a.begin(); it != a.end(); ++it) {
+    typename SmallMap<inner>::const_iterator it_in_b = b.find(it->first);
+    if (it_in_b == b.end() || it_in_b->second != it->second)
+      return false;
   }
+  return true;
 }
 
 template<class inner>
 static bool SmallMapEqual(SmallMap<inner> const& a,
                           SmallMap<inner> const& b) {
-  inner ia, ib;
-  SmallMapToMap(a, &ia);
-  SmallMapToMap(b, &ib);
-
-  // On most systems we can use operator== here, but under some lesser STL
-  // implementations it doesn't seem to work. So we manually compare.
-  if (ia.size() != ib.size())
-    return false;
-  for (typename inner::iterator ia_it = ia.begin(), ib_it = ib.begin();
-       ia_it != ia.end(); ++ia_it, ++ib_it) {
-    if (*ia_it != *ib_it)
-      return false;
-  }
-  return true;
+  return SmallMapIsSubset(a, b) && SmallMapIsSubset(b, a);
 }
 
 TEST(SmallMap, AssignmentOperator) {
   SmallMap<hash_map<int, int> > src_small;
   SmallMap<hash_map<int, int> > src_large;
 
   src_small[1] = 20;
   src_small[2] = 21;
   src_small[3] = 22;
   EXPECT_FALSE(src_small.UsingFullMap());
@@ skipping 308 matching lines @@
   EXPECT_EQ(4u, m.size());
   EXPECT_EQ(0u, m.count(-1));
 
   m[5] = 5;
   EXPECT_EQ(6u, m.size());
   // Our functor adds an extra item when we convert to a map.
   EXPECT_EQ(1u, m.count(-1));
 }
 
 }  // namespace base