Allow the code buffer to automatically grow when aligning.

Change-Id: I7ce93373ddc193fa73a600dcc13fc92e704a4743
diff --git a/test/test-code-buffer.cc b/test/test-code-buffer.cc
new file mode 100644
index 0000000..06c3c83
--- /dev/null
+++ b/test/test-code-buffer.cc
@@ -0,0 +1,53 @@
+// Copyright 2016, VIXL authors
+// All rights reserved.
+//
+// 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 ARM Limited 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 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.
+
+
+#include "code-buffer-vixl.h"
+#include "test-runner.h"
+
+namespace vixl {
+
+#define TEST(name)  TEST_(CODE_BUFFER_##name)
+
+TEST(align_grow) {
+  CodeBuffer code_buffer(2);
+  VIXL_CHECK(code_buffer.GetCapacity() == 2);
+  VIXL_CHECK(code_buffer.GetRemainingBytes() == 2);
+
+  code_buffer.Emit16(0);
+  VIXL_CHECK(code_buffer.GetCapacity() == 2);
+  VIXL_CHECK(code_buffer.GetRemainingBytes() == 0);
+
+  // Check that the buffer can automatically grow when aligning the cursor.
+  VIXL_CHECK(IsAligned<2>(code_buffer.GetCursorOffset()));
+  code_buffer.Align();
+  VIXL_CHECK(IsWordAligned(code_buffer.GetCursorOffset()));
+  VIXL_CHECK(code_buffer.GetCapacity() > 2);
+
+  code_buffer.SetClean();
+}
+
+}  // namespace vixl