diff --git a/internal/ceres/parameter_block_test.cc b/internal/ceres/parameter_block_test.cc
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+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2010, 2011, 2012 Google Inc. All rights reserved.
+// http://code.google.com/p/ceres-solver/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright notice,
+//   this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright notice,
+//   this list of conditions and the following disclaimer in the documentation
+//   and/or other materials provided with the distribution.
+// * Neither the name of Google Inc. nor the names of its contributors may be
+//   used to endorse or promote products derived from this software without
+//   specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+// Author: keir@google.com (Keir Mierle)
+
+#include "ceres/parameter_block.h"
+
+#include "gtest/gtest.h"
+#include "ceres/internal/eigen.h"
+
+namespace ceres {
+namespace internal {
+
+TEST(ParameterBlock, SetLocalParameterization) {
+  double x[3] = { 1.0, 2.0, 3.0 };
+  ParameterBlock parameter_block(x, 3);
+
+  // The indices to set constant within the parameter block (used later).
+  vector<int> indices;
+  indices.push_back(1);
+
+  // Can't set the parameterization if the sizes don't match.
+  SubsetParameterization subset_wrong_size(4, indices);
+  ASSERT_DEATH(parameter_block.SetParameterization(&subset_wrong_size),
+               "global");
+
+  // Can't set parameterization to NULL from NULL.
+  ASSERT_DEATH(parameter_block.SetParameterization(NULL), "NULL");
+
+  // Now set the parameterization.
+  SubsetParameterization subset(3, indices);
+  parameter_block.SetParameterization(&subset);
+
+  // Re-setting the parameterization to the same value is supported.
+  parameter_block.SetParameterization(&subset);
+
+  // Can't set parameterization to NULL from another parameterization.
+  ASSERT_DEATH(parameter_block.SetParameterization(NULL), "NULL");
+
+  // Can't set the parameterization more than once.
+  SubsetParameterization subset_different(3, indices);
+  ASSERT_DEATH(parameter_block.SetParameterization(&subset_different),
+               "re-set");
+
+  // Ensure the local parameterization jacobian result is correctly computed.
+  ConstMatrixRef local_parameterization_jacobian(
+      parameter_block.LocalParameterizationJacobian(),
+      3,
+      2);
+  ASSERT_EQ(1.0, local_parameterization_jacobian(0, 0));
+  ASSERT_EQ(0.0, local_parameterization_jacobian(0, 1));
+  ASSERT_EQ(0.0, local_parameterization_jacobian(1, 0));
+  ASSERT_EQ(0.0, local_parameterization_jacobian(1, 1));
+  ASSERT_EQ(0.0, local_parameterization_jacobian(2, 0));
+  ASSERT_EQ(1.0, local_parameterization_jacobian(2, 1));
+
+  // Check that updating works as expected.
+  double x_plus_delta[3];
+  double delta[2] = { 0.5, 0.3 };
+  parameter_block.Plus(x, delta, x_plus_delta);
+  ASSERT_EQ(1.5, x_plus_delta[0]);
+  ASSERT_EQ(2.0, x_plus_delta[1]);
+  ASSERT_EQ(3.3, x_plus_delta[2]);
+}
+
+struct TestParameterization : public LocalParameterization {
+ public:
+  virtual ~TestParameterization() {}
+  virtual bool Plus(const double* x,
+                    const double* delta,
+                    double* x_plus_delta) const {
+    LOG(FATAL) << "Shouldn't get called.";
+    return true;
+  }
+  virtual bool ComputeJacobian(const double* x,
+                               double* jacobian) const {
+    jacobian[0] = *x * 2;
+    return true;
+  }
+
+  virtual int GlobalSize() const { return 1; }
+  virtual int LocalSize() const { return 1; }
+};
+
+TEST(ParameterBlock, SetStateUpdatesLocalParameterizationJacobian) {
+  TestParameterization test_parameterization;
+  double x[1] = { 1.0 };
+  ParameterBlock parameter_block(x, 1, &test_parameterization);
+
+  EXPECT_EQ(2.0, *parameter_block.LocalParameterizationJacobian());
+
+  x[0] = 5.5;
+  parameter_block.SetState(x);
+  EXPECT_EQ(11.0, *parameter_block.LocalParameterizationJacobian());
+}
+
+TEST(ParameterBlock, PlusWithNoLocalParameterization) {
+  double x[2] = { 1.0, 2.0 };
+  ParameterBlock parameter_block(x, 2);
+
+  double delta[2] = { 0.2, 0.3 };
+  double x_plus_delta[2];
+  parameter_block.Plus(x, delta, x_plus_delta);
+  EXPECT_EQ(1.2, x_plus_delta[0]);
+  EXPECT_EQ(2.3, x_plus_delta[1]);
+}
+
+// Stops computing the jacobian after the first time.
+class BadLocalParameterization : public LocalParameterization {
+ public:
+  BadLocalParameterization()
+      : calls_(0) {
+  }
+
+  virtual ~BadLocalParameterization() {}
+  virtual bool Plus(const double* x,
+                    const double* delta,
+                    double* x_plus_delta) const {
+    *x_plus_delta = *x + *delta;
+    return true;
+  }
+
+  virtual bool ComputeJacobian(const double* x, double* jacobian) const {
+    if (calls_ == 0) {
+      jacobian[0] = 0;
+    }
+    ++calls_;
+    return true;
+  }
+
+  virtual int GlobalSize() const { return 1;}
+  virtual int LocalSize()  const { return 1;}
+
+ private:
+  mutable int calls_;
+};
+
+TEST(ParameterBlock, DetectBadLocalParameterization) {
+  double x = 1;
+  BadLocalParameterization bad_parameterization;
+  ParameterBlock parameter_block(&x, 1, &bad_parameterization);
+  double y = 2;
+  EXPECT_FALSE(parameter_block.SetState(&y));
+}
+
+}  // namespace internal
+}  // namespace ceres