Tests: initial test in initializing lib and loading a backend

- The default backend test will generally fail because
   the backend isn't installed
 - Test known backends if they are built, by passing full path

CMakeLists.txt

@@ -108,3 +108,6 @@ set_target_properties( kpmcore
 message(STATUS "kpmcore ${VERSION} will be built for install into ${CMAKE_INSTALL_PREFIX}")
 
 feature_summary(WHAT ALL INCLUDE_QUIET_PACKAGES FATAL_ON_MISSING_REQUIRED_PACKAGES)
+
+enable_testing()
+add_subdirectory(test)

test/CMakeLists.txt

@@ -0,0 +1,35 @@
+# Tests for KPMcore
+#
+# These are not so much "tests" as "small example programs". They illustrate
+# how to use the library, how to perform common tasks.
+
+set(CMAKE_SKIP_BUILD_RPATH  FALSE)
+SET(CMAKE_BUILD_WITH_INSTALL_RPATH FALSE)
+set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
+
+include_directories(${CMAKE_SOURCE_DIR}/src)  # To get at KPMcore headers
+add_compile_options(-fPIC)
+
+###
+#
+# Helper macro to link to the helper (for initialization of kpmcore)
+# and to add a test with the given name.
+#
+add_library(testhelpers OBJECT helpers.cpp)
+
+macro (kpm_test name)
+    add_executable(${name} ${ARGN} $<TARGET_OBJECTS:testhelpers>)
+    target_link_libraries(${name} kpmcore)
+    add_test(${name} ${name})
+endmacro()
+
+###
+#
+# Tests of initialization: try explicitly loading some backends
+kpm_test(testinit testinit.cpp)  # Default backend
+if(TARGET pmdummybackendplugin)
+    add_test(NAME testinit-dummy COMMAND testinit $<TARGET_FILE:pmdummybackendplugin>)
+endif()
+if(TARGET pmlibpartedbackendplugin)
+    add_test(NAME testinit-parted COMMAND testinit $<TARGET_FILE:pmlibpartedbackendplugin>)
+endif()

test/helpers.cpp

@@ -0,0 +1,47 @@
+#include "helpers.h"
+
+#include "backend/corebackendmanager.h"
+
+#include <QDebug>
+#include <QString>
+
+static bool s_KPMcoreInited = false;
+
+KPMCoreInitializer::KPMCoreInitializer() :
+    m_isValid( s_KPMcoreInited )
+{
+    if ( !s_KPMcoreInited )
+    {
+        QByteArray env = qgetenv( "KPMCORE_BACKEND" );
+        auto backendName = env.isEmpty() ? CoreBackendManager::defaultBackendName() : QString::fromLatin1(env);
+
+        if ( !CoreBackendManager::self()->load( backendName ) )
+        {
+            qWarning() << "Failed to load backend plugin" << backendName;
+        }
+        else
+        {
+            m_isValid = s_KPMcoreInited = true;
+        }
+    }
+}
+
+KPMCoreInitializer::KPMCoreInitializer(const QString& backendName) :
+    m_isValid( s_KPMcoreInited )
+{
+    if (!s_KPMcoreInited)
+    {
+        if ( !CoreBackendManager::self()->load( backendName ) )
+        {
+            qWarning() << "Failed to load backend plugin" << backendName;
+        }
+        else
+        {
+            m_isValid = s_KPMcoreInited = true;
+        }
+    }
+}
+
+KPMCoreInitializer::KPMCoreInitializer(const char *backend) : KPMCoreInitializer( QString::fromLatin1(backend) )
+{
+}

test/helpers.h

@@ -0,0 +1,18 @@
+#ifndef TEST_KPMHELPERS_H
+#define TEST_KPMHELPERS_H
+
+class QString;
+
+class KPMCoreInitializer
+{
+public:
+    KPMCoreInitializer();
+    KPMCoreInitializer(const QString& backend);
+    KPMCoreInitializer(const char *backend);
+
+    bool isValid() const { return m_isValid; }
+private:
+    bool m_isValid;
+} ;
+
+#endif

test/testinit.cpp

@@ -0,0 +1,16 @@
+#include "helpers.h"
+
+int main(int argc, char **argv)
+{
+    if (argc != 2)
+    {
+        KPMCoreInitializer i;
+        return i.isValid() ? 0 : 1;
+    }
+    else
+    {
+        KPMCoreInitializer i(argv[1]);
+        return i.isValid() ? 0 : 1;
+    }
+}
+