Callback API Change: Allow Bind() to take a Callback<> and bind all its free parameters.

base/bind_unittest.cc

 // Copyright (c) 2011 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/bind.h"
 
 #include "base/callback.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 135 matching lines @@
 }
 
 int ArrayGet(const int array[], int n) {
   return array[n];
 }
 
 int Sum(int a, int b, int c, int d, int e, int f) {
   return a + b + c + d + e + f;
 }
 
+void OutputSum(int* output, int a, int b, int c, int d, int e) {
+  *output = a + b + c + d + e;
+}
+
 const char* CStringIdentity(const char* s) {
   return s;
 }
 
 int GetCopies(const CopyCounter& counter) {
   return counter.copies();
 }
 
 int UnwrapNoRefParent(NoRefParent p) {
   return p.value;
@@ skipping 70 matching lines @@
   Callback<int(int,int,int,int)> c4 = Bind(&Sum, 32, 16);
   EXPECT_EQ(94, c4.Run(13, 12, 11, 10));
 
   Callback<int(int,int,int,int,int)> c5 = Bind(&Sum, 32);
   EXPECT_EQ(87, c5.Run(13, 12, 11, 10, 9));
 
   Callback<int(int,int,int,int,int,int)> c6 = Bind(&Sum);
   EXPECT_EQ(69, c6.Run(13, 12, 11, 10, 9, 14));
 }
 
+// Bind should be able to take existing Callbacks and convert to a Closure.
+TEST_F(BindTest, CallbackBindMore) {
+  int output = 0;
+  Closure c;
+
+  Callback<void(int)> c1 = Bind(&OutputSum, &output, 16, 8, 4, 2);
+  c = Bind(c1, 10);
+  c.Run();
+  EXPECT_EQ(40, output);
+
+  Callback<void(int,int)> c2 = Bind(&OutputSum, &output, 16, 8, 4);
+  c = Bind(c2, 10, 9);
+  c.Run();
+  EXPECT_EQ(47, output);
+
+  Callback<void(int,int,int)> c3 = Bind(&OutputSum, &output, 16, 8);
+  c = Bind(c3, 10, 9, 8);
+  c.Run();
+  EXPECT_EQ(51, output);
+
+  Callback<void(int,int,int,int)> c4 = Bind(&OutputSum, &output, 16);
+  c = Bind(c4, 10, 9, 8, 7);
+  c.Run();
+  EXPECT_EQ(50, output);
+
+  Callback<void(int,int,int,int,int)> c5 = Bind(&OutputSum, &output);
+  c = Bind(c5, 10, 9, 8, 7, 6);
+  c.Run();
+  EXPECT_EQ(40, output);
+}
+
 // Function type support.
 //   - Normal function.
 //   - Normal function bound with non-refcounted first argument.
 //   - Method bound to non-const object.
 //   - Const method bound to non-const object.
 //   - Const method bound to const object.
 //   - Derived classes can be used with pointers to non-virtual base functions.
 //   - Derived classes can be used with pointers to virtual base functions (and
 //     preserve virtual dispatch).
 TEST_F(BindTest, FunctionTypeSupport) {
@@ skipping 348 matching lines @@
   Callback<int(void)> fastcall_cb = Bind(&FastCallFunc, 1);
   EXPECT_EQ(1, fastcall_cb.Run());
 
   Callback<int(void)> stdcall_cb = Bind(&StdCallFunc, 2);
   EXPECT_EQ(2, stdcall_cb.Run());
 }
 #endif
 
 }  // namespace
 }  // namespace base