Remove INHIBIT & CONDITIONAL flavor format

The current approach is not optimal due to being a special case
with the abuse of the MEF attributes mechanism.
INHIBIT gate must be implemented properly with dynamic analysis.
The changes are backward compatible
since these flavors had no effect on the analysis.

Issue #28
Issue #29

doc/fault_tree_analysis.rst

@@ -44,7 +44,6 @@ Supported Gate Types
 - NAND
 - XOR
 - NULL
-- INHIBIT
 - ATLEAST
 
 
@@ -56,7 +55,6 @@ Supported Event Types
 - Basic
 - House
 - Undeveloped
-- Conditional
 
 .. note:: Top and intermediate events are gates of an acyclic "fault-tree" graph ([PDAG]_).
 
@@ -67,34 +65,18 @@ Supported Event Types
     since the "fault-tree" is properly treated as a graph/container.
 
 
-Representation of INHIBIT, Undeveloped, and Conditional
-=======================================================
+Representation of Undeveloped
+=============================
 
-These gate and event types are not directly supported
-by the input format based on the Open-PSA [MEF]_.
-Indeed, these types are treated just like AND gate and Basic event respectively;
-therefore, the description of these types
-can be given through the Open-PSA MEF "attribute" element for gates and events.
-The attribute name "flavor" is used to indicate
-the different representation of an event as shown in the description bellow.
-
-
-INHIBIT
--------
-
-Add this XML line to AND gate description:
-:literal:`<attributes> <attribute name="flavor" value="inhibit"/> </attributes>`
+SCRAM currently "abuses" the Open-PSA [MEF]_ attributes mechanism
+to add inessential (for analysis) meta-information.
+This approach still ensures that the input file is portable across tools.
+Attribute "flavor" is used to indicate
+different representations of an event as shown in the description bellow.
 
 
 Undeveloped
 -----------
 
 Add this XML line to basic event description:
 :literal:`<attributes> <attribute name="flavor" value="undeveloped"/> </attributes>`
-
-
-Conditional
------------
-
-Add this XML line to basic event description:
-:literal:`<attributes> <attribute name="flavor" value="conditional"/> </attributes>`

src/event.cc

@@ -44,35 +44,6 @@ void BasicEvent::Validate() const {
   EnsureProbability(expression_, Event::name());
 }
 
-void Gate::Validate() const {
-  assert(formula_ && "The gate formula is missing.");
-  // Detect inhibit flavor.
-  if (formula_->connective() != kAnd || !Element::HasAttribute("flavor") ||
-      Element::GetAttribute("flavor").value != "inhibit") {
-    return;
-  }
-  if (formula_->args().size() != 2) {
-    SCRAM_THROW(ValidityError(Element::name() +
-                              "INHIBIT gate must have only 2 arguments"));
-  }
-  int num_conditional =
-      boost::count_if(formula_->args(), [](const Formula::Arg& arg) {
-        if (arg.complement)
-          return false;
-
-        if (BasicEvent* const* basic_event =
-                std::get_if<BasicEvent*>(&arg.event)) {
-          return (*basic_event)->HasAttribute("flavor") &&
-                 (*basic_event)->GetAttribute("flavor").value == "conditional";
-        }
-
-        return false;
-      });
-  if (num_conditional != 1)
-    SCRAM_THROW(ValidityError(Element::name() + " : INHIBIT gate must have" +
-                              " exactly one conditional event."));
-}
-
 void Formula::ArgSet::Add(ArgEvent event, bool complement) {
   Event* base = ext::as<Event*>(event);
   if (ext::any_of(args_, [&base](const Arg& arg) {

src/event.h

@@ -190,13 +190,6 @@ class Gate : public Event, public NodeMark {
     return formula;
   }
 
-  /// Checks if a gate is initialized correctly.
-  ///
-  /// @pre The gate formula is set.
-  ///
-  /// @throws ValidityError  Errors in the gate's logic or setup.
-  void Validate() const;
-
  private:
   FormulaPtr formula_;  ///< Boolean formula of this gate.
 };

src/initializer.cc

@@ -429,12 +429,6 @@ void Initializer::Define(const xml::Element& gate_node, Gate* gate) {
   assert(!formulas.empty() && ++formulas.begin() == formulas.end());
   assert(!gate->HasFormula() && "Resetting gate formula");
   gate->formula(GetFormula(*formulas.begin(), gate->base_path()));
-  try {
-    gate->Validate();
-  } catch (ValidityError& err) {
-    err << boost::errinfo_at_line(gate_node.line());
-    throw;
-  }
 }
 
 template <>

tests/event_tests.cc

@@ -285,25 +285,6 @@ TEST_CASE("FormulaTest.Validate", "[mef::event]") {
   }
 }
 
-TEST_CASE("MEFGateTest.Inhibit", "[mef::event]") {
-  BasicEvent arg_one("a");
-  BasicEvent arg_two("b");
-  BasicEvent arg_three("c");
-  // INHIBIT Gate tests.
-  Gate top("top");
-  top.AddAttribute({"flavor", "inhibit"});
-  top.formula(FormulaPtr(new Formula(kAnd, {&arg_one, &arg_two})));
-  CHECK_THROWS_AS(top.Validate(), ValidityError);
-  arg_one.AddAttribute({"flavor", "conditional"});
-  CHECK_NOTHROW(top.Validate());
-  arg_two.AddAttribute({"flavor", "conditional"});
-  CHECK_THROWS_AS(top.Validate(), ValidityError);
-  arg_two.RemoveAttribute("flavor");
-  CHECK_NOTHROW(top.Validate());
-  top.formula(FormulaPtr(new Formula(kAnd, {&arg_one, &arg_two, &arg_three})));
-  CHECK_THROWS_AS(top.Validate(), ValidityError);
-}
-
 TEST_CASE("PrimaryEventTest.HouseProbability", "[mef::event]") {
   // House primary event.
   HouseEvent primary("valve");