diff --git a/test_suite/FGTestApi/testGlobals.cxx b/test_suite/FGTestApi/testGlobals.cxx
index a867827e8..8c9587fd0 100644
--- a/test_suite/FGTestApi/testGlobals.cxx
+++ b/test_suite/FGTestApi/testGlobals.cxx
@@ -1,3 +1,8 @@
+/* 
+SPDX-Copyright: James Turner
+SPDX-License-Identifier: GPL-2.0-or-later 
+*/
+
 #include "config.h"
 
 #include "test_suite/dataStore.hxx"
@@ -445,7 +450,15 @@ bool executeNasal(const std::string& code)
 
     return ok;
 }
-    
+
+SGPropertyNode_ptr propsFromString(const std::string& s)
+{
+    SGPropertyNode_ptr m = new SGPropertyNode;
+    std::istringstream iss(s);
+    readProperties(iss, m);
+    return m;
+}
+
 namespace tearDown {
 
 void shutdownTestGlobals()
diff --git a/test_suite/FGTestApi/testGlobals.hxx b/test_suite/FGTestApi/testGlobals.hxx
index 9e69dfd42..f8bd4e371 100644
--- a/test_suite/FGTestApi/testGlobals.hxx
+++ b/test_suite/FGTestApi/testGlobals.hxx
@@ -1,11 +1,16 @@
-#ifndef FG_TEST_GLOBALS_HELPERS_HXX
-#define FG_TEST_GLOBALS_HELPERS_HXX
+/* 
+SPDX-Copyright: James Turner
+SPDX-License-Identifier: GPL-2.0-or-later 
+*/
+
+#pragma once
 
 #include <string>
 #include <functional>
 #include <vector>
 
 #include <simgear/math/SGGeod.hxx>
+#include <simgear/props/propsfwd.hxx>
 #include <simgear/structure/SGSharedPtr.hxx>
 
 namespace flightgear
@@ -42,6 +47,8 @@ void populateFPWithNasal(flightgear::FlightPlanRef f,
 
 // helpers during tests
 
+SGPropertyNode_ptr propsFromString(const std::string& s);
+
 const SGGeod getPosition();    
 void setPosition(const SGGeod& g);
 void setPositionAndStabilise(const SGGeod& g);
@@ -71,5 +78,3 @@ void shutdownTestGlobals();
 }  // End of namespace tearDown.
 
 }  // End of namespace FGTestApi.
-
-#endif // of FG_TEST_GLOBALS_HELPERS_HXX
diff --git a/test_suite/simgear_tests/props/CMakeLists.txt b/test_suite/simgear_tests/props/CMakeLists.txt
index 7484f438b..9dcb3e6bd 100644
--- a/test_suite/simgear_tests/props/CMakeLists.txt
+++ b/test_suite/simgear_tests/props/CMakeLists.txt
@@ -2,11 +2,13 @@ set(TESTSUITE_SOURCES
     ${TESTSUITE_SOURCES}
     ${CMAKE_CURRENT_SOURCE_DIR}/TestSuite.cxx
     ${CMAKE_CURRENT_SOURCE_DIR}/test_props.cxx
+    ${CMAKE_CURRENT_SOURCE_DIR}/test_condition.cxx
     PARENT_SCOPE
 )
 
 set(TESTSUITE_HEADERS
     ${TESTSUITE_HEADERS}
     ${CMAKE_CURRENT_SOURCE_DIR}/test_props.hxx
+    ${CMAKE_CURRENT_SOURCE_DIR}/test_condition.hxx
     PARENT_SCOPE
 )
diff --git a/test_suite/simgear_tests/props/TestSuite.cxx b/test_suite/simgear_tests/props/TestSuite.cxx
index 355416abc..bd8d26e91 100644
--- a/test_suite/simgear_tests/props/TestSuite.cxx
+++ b/test_suite/simgear_tests/props/TestSuite.cxx
@@ -17,8 +17,9 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include "test_condition.hxx"
 #include "test_props.hxx"
 
-
 // Set up the tests.
 CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(SimgearPropsTests, "Simgear unit tests");
+CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(SimgearConditionTests, "Simgear unit tests");
diff --git a/test_suite/simgear_tests/props/test_condition.cxx b/test_suite/simgear_tests/props/test_condition.cxx
new file mode 100644
index 000000000..4a1c5714b
--- /dev/null
+++ b/test_suite/simgear_tests/props/test_condition.cxx
@@ -0,0 +1,50 @@
+/* 
+SPDX-Copyright: James Turner
+SPDX-License-Identifier: GPL-2.0-or-later 
+*/
+
+
+#include "test_condition.hxx"
+
+#include <simgear/props/condition.hxx>
+#include <simgear/props/props.hxx>
+#include <simgear/structure/exception.hxx>
+
+#include <simgear/debug/logstream.hxx>
+
+#include "test_suite/FGTestApi/testGlobals.hxx"
+
+// Set up function for each test.
+void SimgearConditionTests::setUp()
+{
+    // Create a property tree.
+    tree = new SGPropertyNode;
+}
+
+
+// Clean up SimgearConditionTests each test.
+void SimgearConditionTests::tearDown()
+{
+}
+
+
+// Test property aliasing, to catch possible memory leaks.
+void SimgearConditionTests::testEmptyCondition()
+{
+    auto config = FGTestApi::propsFromString(R"(<?xml version="1.0" encoding="UTF-8"?>
+                                    <PropertyList>
+                                       <enabled>/foo/bar</enabled>
+                                    </PropertyList>
+                                    )");
+
+    sglog().setDeveloperMode(true);
+
+    CPPUNIT_ASSERT_THROW(sgReadCondition(tree, config->getChild("enabled")), sg_exception);
+
+    // repeat in non-developer mode; test the legacy behaviour
+    sglog().setDeveloperMode(false);
+
+    auto n2 = sgReadCondition(tree, config->getChild("enabled"));
+    CPPUNIT_ASSERT(n2);
+    CPPUNIT_ASSERT(n2->test());
+}
\ No newline at end of file
diff --git a/test_suite/simgear_tests/props/test_condition.hxx b/test_suite/simgear_tests/props/test_condition.hxx
new file mode 100644
index 000000000..d52ed455d
--- /dev/null
+++ b/test_suite/simgear_tests/props/test_condition.hxx
@@ -0,0 +1,36 @@
+/* 
+SPDX-Copyright: James Turner
+SPDX-License-Identifier: GPL-2.0-or-later 
+*/
+
+#pragma once
+
+
+#include <cppunit/TestFixture.h>
+#include <cppunit/extensions/HelperMacros.h>
+
+#include <simgear/props/condition.hxx>
+#include <simgear/props/propsfwd.hxx>
+
+// The unit tests of the simgear property tree.
+class SimgearConditionTests : public CppUnit::TestFixture
+{
+    // Set up the test suite.
+    CPPUNIT_TEST_SUITE(SimgearConditionTests);
+    CPPUNIT_TEST(testEmptyCondition);
+    CPPUNIT_TEST_SUITE_END();
+
+public:
+    // Set up function for each test.
+    void setUp();
+
+    // Clean up after each test.
+    void tearDown();
+
+    // The tests.
+    void testEmptyCondition();
+
+private:
+    // A property tree.
+    SGPropertyNode_ptr tree;
+};