Unify C++, Dart, Go runtimes

Signed-off-by: Ivan Kochurkin <[email protected]>

runtime/Cpp/runtime/src/atn/ATNConfig.cpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
  * Use of this file is governed by the BSD 3-clause license that
  * can be found in the LICENSE.txt file in the project root.
  */
@@ -23,7 +23,7 @@ inline constexpr size_t SUPPRESS_PRECEDENCE_FILTER = 0x40000000;
 }
 
 ATNConfig::ATNConfig(ATNState *state, size_t alt, Ref<const PredictionContext> context)
-    : ATNConfig(state, alt, std::move(context), 0, SemanticContext::NONE) {}
+    : ATNConfig(state, alt, std::move(context), 0, SemanticContext::Predicate::NONE) {}
 
 ATNConfig::ATNConfig(ATNState *state, size_t alt, Ref<const PredictionContext> context, Ref<const SemanticContext> semanticContext)
     : ATNConfig(state, alt, std::move(context), 0, std::move(semanticContext)) {}
@@ -94,7 +94,7 @@ std::string ATNConfig::toString(bool showAlt) const {
   if (context) {
     ss << ",[" << context->toString() << "]";
   }
-  if (semanticContext != nullptr && semanticContext != SemanticContext::NONE) {
+  if (semanticContext != nullptr && semanticContext != SemanticContext::Predicate::NONE) {
     ss << ",[" << semanticContext->toString() << "]";
   }
   if (getOuterContextDepth() > 0) {

runtime/Cpp/runtime/src/atn/ATNConfigSet.cpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
  * Use of this file is governed by the BSD 3-clause license that
  * can be found in the LICENSE.txt file in the project root.
  */
@@ -43,7 +43,7 @@ bool ATNConfigSet::add(const Ref<ATNConfig> &config, PredictionContextMergeCache
   if (_readonly) {
     throw IllegalStateException("This set is readonly");
   }
-  if (config->semanticContext != SemanticContext::NONE) {
+  if (config->semanticContext != SemanticContext::Predicate::NONE) {
     hasSemanticContext = true;
   }
   if (config->getOuterContextDepth() > 0) {
@@ -114,7 +114,7 @@ std::vector<Ref<const SemanticContext>> ATNConfigSet::getPredicates() const {
   std::vector<Ref<const SemanticContext>> preds;
   preds.reserve(configs.size());
   for (const auto &c : configs) {
-    if (c->semanticContext != SemanticContext::NONE) {
+    if (c->semanticContext != SemanticContext::Predicate::NONE) {
       preds.push_back(c->semanticContext);
     }
   }

runtime/Cpp/runtime/src/atn/ParserATNSimulator.cpp

@@ -692,8 +692,8 @@ std::vector<Ref<const SemanticContext>> ParserATNSimulator::getPredsForAmbigAlts
   size_t nPredAlts = 0;
   for (size_t i = 1; i <= nalts; i++) {
     if (altToPred[i] == nullptr) {
-      altToPred[i] = SemanticContext::NONE;
-    } else if (altToPred[i] != SemanticContext::NONE) {
+      altToPred[i] = SemanticContext::Predicate::NONE;
+    } else if (altToPred[i] != SemanticContext::Predicate::NONE) {
       nPredAlts++;
     }
   }
@@ -712,7 +712,7 @@ std::vector<Ref<const SemanticContext>> ParserATNSimulator::getPredsForAmbigAlts
 std::vector<dfa::DFAState::PredPrediction> ParserATNSimulator::getPredicatePredictions(const antlrcpp::BitSet &ambigAlts,
                                                                                        const std::vector<Ref<const SemanticContext>> &altToPred) {
   bool containsPredicate = std::find_if(altToPred.begin(), altToPred.end(), [](const Ref<const SemanticContext> &context) {
-    return context != SemanticContext::NONE;
+    return context != SemanticContext::Predicate::NONE;
   }) != altToPred.end();
   std::vector<dfa::DFAState::PredPrediction> pairs;
   if (containsPredicate) {
@@ -767,7 +767,7 @@ std::pair<ATNConfigSet *, ATNConfigSet *> ParserATNSimulator::splitAccordingToSe
   ATNConfigSet *succeeded(new ATNConfigSet(configs->fullCtx));
   ATNConfigSet *failed(new ATNConfigSet(configs->fullCtx));
   for (const auto &c : configs->configs) {
-    if (c->semanticContext != SemanticContext::NONE) {
+    if (c->semanticContext != SemanticContext::Predicate::NONE) {
       bool predicateEvaluationResult = evalSemanticContext(c->semanticContext, outerContext, c->alt, configs->fullCtx);
       if (predicateEvaluationResult) {
         succeeded->add(c);
@@ -785,7 +785,7 @@ BitSet ParserATNSimulator::evalSemanticContext(const std::vector<dfa::DFAState::
                                                ParserRuleContext *outerContext, bool complete) {
   BitSet predictions;
   for (const auto &prediction : predPredictions) {
-    if (prediction.pred == SemanticContext::NONE) {
+    if (prediction.pred == SemanticContext::Predicate::NONE) {
       predictions.set(prediction.alt);
       if (!complete) {
         break;

runtime/Cpp/runtime/src/atn/PredictionMode.cpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
  * Use of this file is governed by the BSD 3-clause license that
  * can be found in the LICENSE.txt file in the project root.
  */
@@ -62,7 +62,7 @@ bool PredictionModeClass::hasSLLConflictTerminatingPrediction(PredictionMode mod
     // dup configs, tossing out semantic predicates
     ATNConfigSet dup(true);
     for (auto &config : configs->configs) {
-      Ref<ATNConfig> c = std::make_shared<ATNConfig>(*config, SemanticContext::NONE);
+      Ref<ATNConfig> c = std::make_shared<ATNConfig>(*config, SemanticContext::Predicate::NONE);
       dup.add(c);
     }
     std::vector<antlrcpp::BitSet> altsets = getConflictingAltSubsets(&dup);

runtime/Cpp/runtime/src/atn/SemanticContext.cpp

@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
  * Use of this file is governed by the BSD 3-clause license that
  * can be found in the LICENSE.txt file in the project root.
  */
@@ -137,7 +137,7 @@ bool SemanticContext::PrecedencePredicate::eval(Recognizer *parser, RuleContext
 Ref<const SemanticContext> SemanticContext::PrecedencePredicate::evalPrecedence(Recognizer *parser,
   RuleContext *parserCallStack) const {
   if (parser->precpred(parserCallStack, precedence)) {
-    return SemanticContext::NONE;
+    return SemanticContext::Predicate::NONE;
   }
   return nullptr;
 }
@@ -237,7 +237,7 @@ Ref<const SemanticContext> SemanticContext::AND::evalPrecedence(Recognizer *pars
       // The AND context is false if any element is false.
       return nullptr;
     }
-    if (evaluated != NONE) {
+    if (evaluated != Predicate::NONE) {
       // Reduce the result by skipping true elements.
       operands.push_back(std::move(evaluated));
     }
@@ -249,7 +249,7 @@ Ref<const SemanticContext> SemanticContext::AND::evalPrecedence(Recognizer *pars
 
   if (operands.empty()) {
     // All elements were true, so the AND context is true.
-    return NONE;
+    return Predicate::NONE;
   }
 
   Ref<const SemanticContext> result = std::move(operands[0]);
@@ -337,9 +337,9 @@ Ref<const SemanticContext> SemanticContext::OR::evalPrecedence(Recognizer *parse
   for (const auto &context : getOperands()) {
     auto evaluated = context->evalPrecedence(parser, parserCallStack);
     differs |= (evaluated != context);
-    if (evaluated == NONE) {
+    if (evaluated == Predicate::NONE) {
       // The OR context is true if any element is true.
-      return NONE;
+      return Predicate::NONE;
     }
     if (evaluated != nullptr) {
       // Reduce the result by skipping false elements.
@@ -374,18 +374,18 @@ std::string SemanticContext::OR::toString() const {
 
 //------------------ SemanticContext -----------------------------------------------------------------------------------
 
-const Ref<const SemanticContext> SemanticContext::NONE = std::make_shared<Predicate>(INVALID_INDEX, INVALID_INDEX, false);
+const Ref<const SemanticContext> SemanticContext::Predicate::NONE = std::make_shared<Predicate>(INVALID_INDEX, INVALID_INDEX, false);
 
 Ref<const SemanticContext> SemanticContext::evalPrecedence(Recognizer * /*parser*/, RuleContext * /*parserCallStack*/) const {
   return shared_from_this();
 }
 
 Ref<const SemanticContext> SemanticContext::And(Ref<const SemanticContext> a, Ref<const SemanticContext> b) {
-  if (!a || a == NONE) {
+  if (!a || a == Predicate::NONE) {
     return b;
   }
 
-  if (!b || b == NONE) {
+  if (!b || b == Predicate::NONE) {
     return a;
   }
 
@@ -405,8 +405,8 @@ Ref<const SemanticContext> SemanticContext::Or(Ref<const SemanticContext> a, Ref
     return a;
   }
 
-  if (a == NONE || b == NONE) {
-    return NONE;
+  if (a == Predicate::NONE || b == Predicate::NONE) {
+    return Predicate::NONE;
   }
 
   Ref<OR> result = std::make_shared<OR>(std::move(a), std::move(b));

runtime/Cpp/runtime/src/atn/SemanticContext.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
  * Use of this file is governed by the BSD 3-clause license that
  * can be found in the LICENSE.txt file in the project root.
  */
@@ -20,12 +20,6 @@ namespace atn {
   ///  SemanticContext within the scope of this outer class.
   class ANTLR4CPP_PUBLIC SemanticContext : public std::enable_shared_from_this<SemanticContext> {
   public:
-    /**
-     * The default {@link SemanticContext}, which is semantically equivalent to
-     * a predicate of the form {@code {true}?}.
-     */
-    static const Ref<const SemanticContext> NONE;
-
     virtual ~SemanticContext() = default;
 
     SemanticContextType getContextType() const { return _contextType; }
@@ -99,6 +93,12 @@ namespace atn {
 
   class ANTLR4CPP_PUBLIC SemanticContext::Predicate final : public SemanticContext {
   public:
+    /**
+     * The default {@link SemanticContext}, which is semantically equivalent to
+     * a predicate of the form {@code {true}?}.
+     */
+    static const Ref<const SemanticContext> NONE;
+
     static bool is(const SemanticContext &semanticContext) { return semanticContext.getContextType() == SemanticContextType::PREDICATE; }
 
     static bool is(const SemanticContext *semanticContext) { return semanticContext != nullptr && is(*semanticContext); }

runtime/Dart/lib/src/atn/src/atn_config.dart

@@ -89,7 +89,7 @@ class ATNConfig {
     this.state,
     this.alt,
     this.context, [
-    this.semanticContext = SemanticContext.NONE,
+    this.semanticContext = Predicate.NONE,
   ]) : reachesIntoOuterContext = 0;
 
   ATNConfig.dup(
@@ -169,7 +169,7 @@ class ATNConfig {
       buf.write(context.toString());
       buf.write(']');
     }
-    if (semanticContext != SemanticContext.NONE) {
+    if (semanticContext != Predicate.NONE) {
       buf.write(',');
       buf.write(semanticContext);
     }
@@ -194,7 +194,7 @@ class LexerATNConfig extends ATNConfig {
     int alt,
     PredictionContext context, [
     this.lexerActionExecutor,
-  ]) : super(state, alt, context, SemanticContext.NONE) {
+  ]) : super(state, alt, context, Predicate.NONE) {
     passedThroughNonGreedyDecision = false;
   }
 

runtime/Dart/lib/src/atn/src/atn_config_set.dart

@@ -109,7 +109,7 @@ class ATNConfigSet extends Iterable<ATNConfig> {
         mergeCache,
   ]) {
     if (readOnly) throw StateError('This set is readonly');
-    if (config.semanticContext != SemanticContext.NONE) {
+    if (config.semanticContext != Predicate.NONE) {
       hasSemanticContext = true;
     }
     if (config.outerContextDepth > 0) {
@@ -176,7 +176,7 @@ class ATNConfigSet extends Iterable<ATNConfig> {
   List<SemanticContext?> get predicates {
     final preds = <SemanticContext?>[];
     for (var c in configs) {
-      if (c.semanticContext != SemanticContext.NONE) {
+      if (c.semanticContext != Predicate.NONE) {
         preds.add(c.semanticContext);
       }
     }

runtime/Dart/lib/src/atn/src/atn_simulator.dart

@@ -77,7 +77,7 @@ class PredictionContextCache {
   ///  return that one instead and do not add a new context to the cache.
   ///  Protect shared cache from unsafe thread access.
   PredictionContext add(PredictionContext ctx) {
-    if (ctx == PredictionContext.EMPTY) return PredictionContext.EMPTY;
+    if (ctx == EmptyPredictionContext.Instance) return EmptyPredictionContext.Instance;
     final existing = cache[ctx];
     if (existing != null) {
 //			System.out.println(name+" reuses "+existing);

runtime/Dart/lib/src/atn/src/lexer_atn_simulator.dart

@@ -401,7 +401,7 @@ class LexerATNSimulator extends ATNSimulator {
   }
 
   ATNConfigSet computeStartState(CharStream input, ATNState p) {
-    PredictionContext initialContext = PredictionContext.EMPTY;
+    PredictionContext initialContext = EmptyPredictionContext.Instance;
     ATNConfigSet configs = OrderedATNConfigSet();
     for (var i = 0; i < p.numberOfTransitions; i++) {
       final target = p.transition(i).target;
@@ -445,7 +445,7 @@ class LexerATNSimulator extends ATNSimulator {
           configs.add(LexerATNConfig.dup(
             config,
             config.state,
-            context: PredictionContext.EMPTY,
+            context: EmptyPredictionContext.Instance,
           ));
           currentAltReachedAcceptState = true;
         }

runtime/Dart/lib/src/atn/src/parser_atn_simulator.dart

@@ -1234,8 +1234,8 @@ class ParserATNSimulator extends ATNSimulator {
     var nPredAlts = 0;
     for (var i = 1; i <= nalts; i++) {
       if (altToPred[i] == null) {
-        altToPred[i] = SemanticContext.NONE;
-      } else if (altToPred[i] != SemanticContext.NONE) {
+        altToPred[i] = Predicate.NONE;
+      } else if (altToPred[i] != Predicate.NONE) {
         nPredAlts++;
       }
     }
@@ -1266,7 +1266,7 @@ class ParserATNSimulator extends ATNSimulator {
       if (ambigAlts != null && ambigAlts[i]) {
         pairs.add(PredPrediction(pred!, i));
       }
-      if (pred != SemanticContext.NONE) containsPredicate = true;
+      if (pred != Predicate.NONE) containsPredicate = true;
     }
 
     if (!containsPredicate) {
@@ -1370,7 +1370,7 @@ class ParserATNSimulator extends ATNSimulator {
     final succeeded = ATNConfigSet(configs.fullCtx);
     final failed = ATNConfigSet(configs.fullCtx);
     for (var c in configs) {
-      if (c.semanticContext != SemanticContext.NONE) {
+      if (c.semanticContext != Predicate.NONE) {
         final predicateEvaluationResult = evalSemanticContextOne(
           c.semanticContext,
           outerContext,
@@ -1401,7 +1401,7 @@ class ParserATNSimulator extends ATNSimulator {
   ) {
     final predictions = BitSet();
     for (var pair in predPredictions) {
-      if (pair.pred == SemanticContext.NONE) {
+      if (pair.pred == Predicate.NONE) {
         predictions.set(pair.alt);
         if (!complete) {
           break;
@@ -1511,7 +1511,7 @@ class ParserATNSimulator extends ATNSimulator {
                   ATNConfig.dup(
                     config,
                     state: config.state,
-                    context: PredictionContext.EMPTY,
+                    context: EmptyPredictionContext.Instance,
                   ),
                   mergeCache);
               continue;
@@ -2431,7 +2431,7 @@ extension PredictionModeExtension on PredictionMode {
 // dup configs, tossing out semantic predicates
         final dup = ATNConfigSet();
         for (var c in configs) {
-          c = ATNConfig.dup(c, semanticContext: SemanticContext.NONE);
+          c = ATNConfig.dup(c, semanticContext: Predicate.NONE);
           dup.add(c);
         }
         configs = dup;