AP: fix erroneous warning with Monostable FlipFlip

Add a unit-test written by Huntely, and extend the AP configure code, so the
'time' config of monostables doesn't trigger an incorrect warning in the
console / logs.

Thanks to Huntley Palmer for pointing this out.

SF-ID: https://sourceforge.net/p/flightgear/codetickets/2812/

src/Autopilot/component.cxx

@@ -52,12 +52,12 @@ bool Component::configure( SGPropertyNode& prop_root,
     if(    !configure(*child, cname, prop_root)
         && cname != "params" ) // 'params' is usually used to specify parameters
                                // in PropertList files.
-      SG_LOG
-      (
-        SG_AUTOPILOT,
-        SG_INFO,
-        "Component::configure: unknown node: " << cname
-      );
+
+        // consider using the error reporting mechanism here, at level warning
+        SG_LOG(
+            SG_AUTOPILOT,
+            SG_DEV_WARN,
+            "Component::configure: unknown node: " << cname);
   }
 
   return true;

src/Autopilot/flipflop.cxx

@@ -269,6 +269,12 @@ protected:
                           SGPropertyNode& prop_root );
   InputValueList _time;
   double _t;
+
+  bool isConfigProperty(const std::string& cfg_name) const override
+  {
+    return cfg_name == "time";
+  }
+
 public:
   /**
    * @brief constructor for a MonoFlopImplementation
@@ -457,6 +463,12 @@ bool FlipFlop::configure( SGPropertyNode& cfg_node,
     return true;
   }
 
+  if (_implementation && _implementation->isConfigProperty(cfg_name)) {
+    // componentForge CreateAndConfigureFunctor<> already called configure with all the nodes
+    // on our implementation, but we need to ensure we don't return false here for such nodes
+    return true;
+  }
+
   return false; 
 }
 

src/Autopilot/flipflop.hxx

@@ -58,6 +58,8 @@ public:
   */
   bool configure( SGPropertyNode& prop_root,
                   SGPropertyNode& cfg );
+
+  virtual bool isConfigProperty(const std::string& cfg_name) const { return false; }
 };
 
 /**

test_suite/unit_tests/Autopilot/CMakeLists.txt

@@ -5,6 +5,7 @@ set(TESTSUITE_SOURCES
     ${CMAKE_CURRENT_SOURCE_DIR}/testPidController.cxx
     ${CMAKE_CURRENT_SOURCE_DIR}/testPidControllerData.cxx
     ${CMAKE_CURRENT_SOURCE_DIR}/testInputValue.cxx
+    ${CMAKE_CURRENT_SOURCE_DIR}/testMonostable.cxx
     PARENT_SCOPE
 )
 
@@ -14,5 +15,6 @@ set(TESTSUITE_HEADERS
     ${CMAKE_CURRENT_SOURCE_DIR}/testPidController.hxx
     ${CMAKE_CURRENT_SOURCE_DIR}/testPidControllerData.hxx
     ${CMAKE_CURRENT_SOURCE_DIR}/testInputValue.hxx
+    ${CMAKE_CURRENT_SOURCE_DIR}/testMonostable.hxx
     PARENT_SCOPE
 )

test_suite/unit_tests/Autopilot/TestSuite.cxx

@@ -18,10 +18,12 @@
  */
 
 #include "testDigitalFilter.hxx"
-#include "testPidController.hxx"
 #include "testInputValue.hxx"
+#include "testMonostable.hxx"
+#include "testPidController.hxx"
 
 // Set up the unit tests.
+CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(MonostableTests, "Unit tests");
 CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(DigitalFilterTests, "Unit tests");
 CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(PidControllerTests, "Unit tests");
 CPPUNIT_TEST_SUITE_NAMED_REGISTRATION(InputValueTests, "Unit tests");

test_suite/unit_tests/Autopilot/testMonostable.cxx

@@ -0,0 +1,122 @@
+/*
+ * SPDX-FileName: testMonostable.cxx
+ * SPDX-FileComment: Unit tests for monostable autopilot element
+ * SPDX-FileCopyrightText: Copyright (C) 2023 Huntley Palmer
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "testMonostable.hxx"
+
+#include <strstream>
+
+#include "test_suite/FGTestApi/testGlobals.hxx"
+
+
+#include <Autopilot/autopilot.hxx>
+#include <Autopilot/digitalfilter.hxx>
+#include <Main/fg_props.hxx>
+#include <Main/globals.hxx>
+
+
+#include <simgear/math/sg_random.hxx>
+#include <simgear/props/props_io.hxx>
+
+// Set up function for each test.
+void MonostableTests::setUp()
+{
+    FGTestApi::setUp::initTestGlobals("ap-monostable");
+}
+
+
+// Clean up after each test.
+void MonostableTests::tearDown()
+{
+    FGTestApi::tearDown::shutdownTestGlobals();
+}
+
+
+SGPropertyNode_ptr MonostableTests::configFromString(const std::string& s)
+{
+    SGPropertyNode_ptr config = new SGPropertyNode;
+
+    std::istringstream iss(s);
+    readProperties(iss, config);
+    return config;
+}
+
+void MonostableTests::testMonostable()
+{
+    sg_srandom(999);
+    //
+    // Simple monostable            from wiki:
+    //   monostable stable state is false,  true when Set, until timeout
+    //   ( S == False, test/S == 0  ) :  O/P  = 0
+    //   ( S == True , test/S == 1  ) :  O/P  = 1
+    //   ( S == False, test/S == 0  ) :  Timer running,  O/P = 1
+    //   ( S == False, test/S == 0  ) :  Timed out    ,  O/P = 0
+    //
+    //
+    auto config = configFromString(R"(<?xml version="1.0" encoding="UTF-8"?>
+                                    <PropertyList>
+                                    <flipflop>
+                                        <type>monostable</type>
+                                        <S> 
+                                          <property>/test/S</property>
+                                        </S>
+                                        <time>
+                                            <value>0.50</value>
+                                        </time>
+                                        <output>/test/Q</output>
+                                    </flipflop>
+                                    </PropertyList>
+                                    )");
+
+    auto ap = new FGXMLAutopilot::Autopilot(globals->get_props(), config);
+
+    globals->get_subsystem_mgr()->add("ap", ap);
+    ap->bind();
+    ap->init();
+
+    // Initially        test/S is 0  O/P s.b    stable state == 0
+    fgSetBool("/test/S", false);
+    ap->update(0.01);
+    CPPUNIT_ASSERT_EQUAL(false, fgGetBool("/test/Q"));
+
+    // steady input            test/S  = 0  s.b. no change
+    ap->update(0.24);
+    CPPUNIT_ASSERT_EQUAL(false, fgGetBool("/test/Q"));
+
+    // steady           test/S  = 0  s.b. no change during timer
+    ap->update(0.25);
+    CPPUNIT_ASSERT_EQUAL(false, fgGetBool("/test/Q"));
+
+    // steady           test/S  = 0  s.b. no change after timeout
+    ap->update(0.25);
+    CPPUNIT_ASSERT_EQUAL(false, fgGetBool("/test/Q"));
+
+    // Set S input true == 1   O/P should immediately = 1, true
+    fgSetBool("/test/S", true);
+    ap->update(0.01);
+    CPPUNIT_ASSERT_EQUAL(true, fgGetBool("/test/Q"));
+
+    // steady           test/S  = 1  s.b. no change during timer
+    ap->update(0.24);
+    CPPUNIT_ASSERT_EQUAL(true, fgGetBool("/test/Q"));
+
+    // steady           test/S  = 1  s.b. no change after timeout
+    ap->update(0.25);
+    CPPUNIT_ASSERT_EQUAL(true, fgGetBool("/test/Q"));
+
+    // Reset Input               test/S  = 0  s.b. no change
+    fgSetBool("/test/S", false);
+    ap->update(0.01);
+    CPPUNIT_ASSERT_EQUAL(true, fgGetBool("/test/Q"));
+
+    // steady           test/S  = 0  s.b. no change during timer
+    ap->update(0.24);
+    CPPUNIT_ASSERT_EQUAL(true, fgGetBool("/test/Q"));
+
+    // steady           test/S  = 0  O/P resets = 0 after timeout
+    ap->update(0.25);
+    CPPUNIT_ASSERT_EQUAL(false, fgGetBool("/test/Q"));
+}

test_suite/unit_tests/Autopilot/testMonostable.hxx

@@ -0,0 +1,37 @@
+/*
+ * SPDX-FileName: testMonostable.hxx
+ * SPDX-FileComment: Unit tests for monostable autopilot element
+ * SPDX-FileCopyrightText: Copyright (C) 2023 Huntley Palmer
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#pragma once
+
+
+#include <cppunit/TestFixture.h>
+#include <cppunit/extensions/HelperMacros.h>
+
+#include <simgear/props/props.hxx>
+
+
+// The system tests.
+class MonostableTests : public CppUnit::TestFixture
+{
+    // Set up the test suite.
+    CPPUNIT_TEST_SUITE(MonostableTests);
+    CPPUNIT_TEST(testMonostable);
+    CPPUNIT_TEST_SUITE_END();
+
+    SGPropertyNode_ptr configFromString(const std::string& s);
+
+public:
+    // Set up function for each test.
+    void setUp();
+
+    // Clean up after each test.
+    void tearDown();
+
+
+    // The tests.
+    void testMonostable();
+};