Merge branch 'feature/add-test-fifo' into 'master'

Test the FIFO implementation

This merge requests adds a simple unit test for UG's FIFO implementation.

See merge request !18

low/CMakeLists.txt

+add_subdirectory(test)
+
 # normal headers
 set(lowinclude_HEADERS  heaps.h ugenv.h ugstruct.h misc.h debug.h ugtypes.h
   general.h dimension.h boxtree.h ugtimer.h scan.h

low/test/CMakeLists.txt

+dune_add_test(SOURCES test-fifo.cc)
+target_link_libraries(test-fifo ugL2)

low/test/test-fifo.cc

+#include "config.h"
+
+#include <memory>
+
+#include <dune/common/test/testsuite.hh>
+
+#include "../fifo.h"
+
+using namespace Dune;
+
+TestSuite test_fifo()
+{
+  TestSuite test;
+
+  using namespace UG;
+
+  FIFO fifo;
+  const INT size = 32;
+  int items[size];
+  for (int i = 0; i < size; ++i)
+    items[i] = i;
+
+  auto buffer = std::make_unique<void*[]>(size);
+  {
+    const auto result = fifo_init(&fifo, buffer.get(), size * sizeof(void*));
+    test.require(result, "require that fifo_init() suceeds");
+  }
+
+  test.check(fifo_empty(&fifo), "New FIFO must be empty");
+  test.check(!fifo_full(&fifo), "New FIFO must not be full");
+  test.check(fifo_out(&fifo) == nullptr, "New FIFO must not return an element");
+
+  {
+    const auto result = fifo_in(&fifo, &items[0]);
+    test.check(!result, "Inserting an element must succeed");
+  }
+
+  test.check(!fifo_empty(&fifo), "FIFO must not be empty after inserting an element");
+  test.check(!fifo_full(&fifo), "FIFO must not be full after inserting an element");
+
+  {
+    const auto v = static_cast<int*>(fifo_out(&fifo));
+    test.check(v == &items[0], "FIFO must return the item inserted before");
+  }
+
+  test.check(fifo_empty(&fifo), "FIFO must be empty after removing the element again");
+  test.check(!fifo_full(&fifo), "FIFO must not be full after removing the element again");
+
+  for (auto& item : items) {
+    bool result = fifo_in(&fifo, &item);
+    test.check(!result, "Inserting elemens must succeed");
+  }
+
+  test.check(!fifo_empty(&fifo), "FIFO must not be empty after filling it");
+  test.check(fifo_full(&fifo), "FIFO must be full after filling it");
+
+  {
+    bool result = fifo_in(&fifo, &items[0]);
+    test.check(result, "Inserting into a full FIFO must fail");
+  }
+
+  for (auto& item : items) {
+    const auto v = static_cast<int*>(fifo_out(&fifo));
+    test.check(v == &item, "FIFO must return correct item");
+  }
+
+  test.check(fifo_empty(&fifo), "FIFO must be empty after removing all elements");
+  test.check(!fifo_full(&fifo), "FIFO must not be full after removing all elements");
+  test.check(fifo_out(&fifo) == nullptr, "fifo_out() must return nullptr after removing all elements");
+
+  fifo_clear(&fifo);
+
+  return test;
+}
+
+int main()
+{
+  TestSuite test;
+
+  test.subTest(test_fifo());
+
+  return test.exit();
+}