LazyConstructor

libuavcan/test/lazy_constructor.cpp

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2014 Pavel Kirienko <pavel.kirienko@gmail.com>
+ */
+
+#include <gtest/gtest.h>
+#include <uavcan/internal/lazy_constructor.hpp>
+
+
+TEST(LazyConstructor, Basic)
+{
+    using ::uavcan::LazyConstructor;
+
+    LazyConstructor<std::string> a;
+    LazyConstructor<std::string> b;
+
+    ASSERT_FALSE(a);
+    ASSERT_FALSE(b.isConstructed());
+
+    /*
+     * Construction
+     */
+    a.destroy(); // no-op
+    a.construct();
+    b.construct("Hello world");
+
+    ASSERT_TRUE(a);
+    ASSERT_TRUE(b.isConstructed());
+
+    ASSERT_NE(*a, *b);
+    ASSERT_STRNE(a->c_str(), b->c_str());
+
+    ASSERT_EQ(*a, "");
+    ASSERT_EQ(*b, "Hello world");
+
+    /*
+     * Copying
+     */
+    a = b;            // Assignment operator performs destruction and immediate copy construction
+    ASSERT_EQ(*a, *b);
+    ASSERT_EQ(*a, "Hello world");
+
+    LazyConstructor<std::string> c(a); // Copy constructor call is forwarded to std::string
+
+    ASSERT_EQ(*c, *a);
+
+    *a = "123";
+    ASSERT_NE(*c, *a);
+    ASSERT_EQ(*c, *b);
+
+    *c = "456";
+    ASSERT_NE(*a, *c);
+    ASSERT_NE(*b, *a);
+    ASSERT_NE(*c, *b);
+
+    /*
+     * Destruction
+     */
+    ASSERT_TRUE(c);
+    c.destroy();
+    ASSERT_FALSE(c);
+}