diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/cpp/Cpp.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/cpp/Cpp.test.stg
index 88cb9d4ac..224b504eb 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/cpp/Cpp.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/cpp/Cpp.test.stg
@@ -233,7 +233,7 @@ ImportListener(X) ::= ""
 
 GetExpectedTokenNames() ::= "getExpectedTokens().toString(_tokenNames)"
 
-RuleInvocationStack() ::= "str_list(getRuleInvocationStack())"
+RuleInvocationStack() ::= "Arrays::listToString(getRuleInvocationStack(), \", \")"
 
 LL_EXACT_AMBIG_DETECTION() ::= <<getInterpreter\<atn::ParserATNSimulator>()->setPredictionMode(atn::PredictionMode::LL_EXACT_AMBIG_DETECTION);>>
 
@@ -342,31 +342,28 @@ tree::ParseTreeWalker::DEFAULT->walk(std::make_shared\<LeafListener>(), <s>);
 
 TreeNodeWithAltNumField(X) ::= <<
 @parser::members {
-class MyRuleNode(ParserRuleContext):
-    def __init__(self, parent = None, invokingStateNumber = None ):
-        super(<X>Parser.MyRuleNode, self).__init__(parent, invokingStateNumber)
-        altNum = 0;
-    def getAltNumber(self):
-        return altNum
-    def setAltNumber(self, altNum):
-        this->altNum = altNum
+class MyRuleNode : public ParserRuleContext {
+public:
+  int altNum;
+	MyRuleNode(std::weak_ptr\<ParserRuleContext> parent, int invokingStateNumber)
+		: ParserRuleContext(parent, invokingStateNumber) {
+	}
+	virtual int getAltNumber() const override { return altNum; }
+	virtual void setAltNumber(int altNum) override { this->altNum = altNum; }
+};
 }
 >>
 
 TokenGetterListener(X) ::= <<
-if __name__ is not None and "." in __name__:
-    from .<X>Listener import <X>Listener
-else:
-    from <X>Listener import <X>Listener
-
-class LeafListener(TListener):
-    def exitA(self, ctx):
-        if (ctx.getChildCount()==2) {
-            std::cout \<\< ctx.INT(0).symbol.text \<\< " " \<\< ctx.INT(1).symbol.text \<\< " " \<\< str_list(ctx.INT());
-        } else {
-            std::cout \<\< str(ctx.ID().symbol);
+class LeafListener : TBaseListener {
+public:
+  void exitA(Ref\<TParser::AContext> ctx) {
+		if (ctx->getChildCount() == 2)
+			std::cout \<\< ctx->INT(0)->getSymbol()->getText() \<\< ctx->INT(1)->getSymbol()->getText() \<\< ctx->INT() \<\< std::endl;
+		else
+			std::cout \<\< ctx->ID()->getSymbol() \<\< std::endl;
 	}
-
+};
 >>
 
 RuleGetterListener(X) ::= <<
diff --git a/runtime-testsuite/test/org/antlr/v4/test/runtime/cpp/TestParseTrees.java b/runtime-testsuite/test/org/antlr/v4/test/runtime/cpp/TestParseTrees.java
index 0dcc8f422..1cc98cfe1 100644
--- a/runtime-testsuite/test/org/antlr/v4/test/runtime/cpp/TestParseTrees.java
+++ b/runtime-testsuite/test/org/antlr/v4/test/runtime/cpp/TestParseTrees.java
@@ -13,14 +13,14 @@ public class TestParseTrees extends BaseCppTest {
 	public void test2AltLoop() throws Exception {
 		mkdir(tmpdir);
 
-		StringBuilder grammarBuilder = new StringBuilder(146);
+		StringBuilder grammarBuilder = new StringBuilder(147);
 		grammarBuilder.append("grammar T;\n");
 		grammarBuilder.append("s\n");
 		grammarBuilder.append("@init {\n");
-		grammarBuilder.append("_buildParseTrees = true\n");
+		grammarBuilder.append("_buildParseTrees = true;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("@after {\n");
-		grammarBuilder.append("std::cout << $r.ctx.toStringTree(recog=self) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << $r.ctx->toStringTree(this) << std::endl;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("  : r=a ;\n");
 		grammarBuilder.append("a : ('x' | 'y')* 'z'\n");
@@ -41,14 +41,14 @@ public class TestParseTrees extends BaseCppTest {
 	public void test2Alts() throws Exception {
 		mkdir(tmpdir);
 
-		StringBuilder grammarBuilder = new StringBuilder(139);
+		StringBuilder grammarBuilder = new StringBuilder(140);
 		grammarBuilder.append("grammar T;\n");
 		grammarBuilder.append("s\n");
 		grammarBuilder.append("@init {\n");
-		grammarBuilder.append("_buildParseTrees = true\n");
+		grammarBuilder.append("_buildParseTrees = true;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("@after {\n");
-		grammarBuilder.append("std::cout << $r.ctx.toStringTree(recog=self) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << $r.ctx->toStringTree(this) << std::endl;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("  : r=a ;\n");
 		grammarBuilder.append("a : 'x' | 'y'\n");
@@ -69,29 +69,30 @@ public class TestParseTrees extends BaseCppTest {
 	public void testAltNum() throws Exception {
 		mkdir(tmpdir);
 
-		StringBuilder grammarBuilder = new StringBuilder(563);
+		StringBuilder grammarBuilder = new StringBuilder(587);
 		grammarBuilder.append("grammar T;\n");
 		grammarBuilder.append("\n");
 		grammarBuilder.append("options { contextSuperClass=MyRuleNode; }\n");
 		grammarBuilder.append("\n");
 		grammarBuilder.append("@parser::members {\n");
-		grammarBuilder.append("class MyRuleNode(ParserRuleContext):\n");
-		grammarBuilder.append("    def __init__(self, parent = None, invokingStateNumber = None ):\n");
-		grammarBuilder.append("        super(TParser.MyRuleNode, self).__init__(parent, invokingStateNumber)\n");
-		grammarBuilder.append("        altNum = 0;\n");
-		grammarBuilder.append("    def getAltNumber(self):\n");
-		grammarBuilder.append("        return altNum\n");
-		grammarBuilder.append("    def setAltNumber(self, altNum):\n");
-		grammarBuilder.append("        this->altNum = altNum\n");
+		grammarBuilder.append("class MyRuleNode : public ParserRuleContext {\n");
+		grammarBuilder.append("public:\n");
+		grammarBuilder.append("  int altNum;\n");
+		grammarBuilder.append("	MyRuleNode(std::weak_ptr<ParserRuleContext> parent, int invokingStateNumber)\n");
+		grammarBuilder.append("		: ParserRuleContext(parent, invokingStateNumber) {\n");
+		grammarBuilder.append("	}\n");
+		grammarBuilder.append("	virtual int getAltNumber() const override { return altNum; }\n");
+		grammarBuilder.append("	virtual void setAltNumber(int altNum) override { this->altNum = altNum; }\n");
+		grammarBuilder.append("};\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("\n");
 		grammarBuilder.append("\n");
 		grammarBuilder.append("s\n");
 		grammarBuilder.append("@init {\n");
-		grammarBuilder.append("_buildParseTrees = true\n");
+		grammarBuilder.append("_buildParseTrees = true;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("@after {\n");
-		grammarBuilder.append("std::cout << $r.ctx.toStringTree(recog=self) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << $r.ctx->toStringTree(this) << std::endl;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("  : r=a ;\n");
 		grammarBuilder.append("\n");
@@ -117,14 +118,14 @@ public class TestParseTrees extends BaseCppTest {
 	public void testExtraToken() throws Exception {
 		mkdir(tmpdir);
 
-		StringBuilder grammarBuilder = new StringBuilder(152);
+		StringBuilder grammarBuilder = new StringBuilder(153);
 		grammarBuilder.append("grammar T;\n");
 		grammarBuilder.append("s\n");
 		grammarBuilder.append("@init {\n");
-		grammarBuilder.append("_buildParseTrees = true\n");
+		grammarBuilder.append("_buildParseTrees = true;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("@after {\n");
-		grammarBuilder.append("std::cout << $r.ctx.toStringTree(recog=self) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << $r.ctx->toStringTree(this) << std::endl;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("  : r=a ;\n");
 		grammarBuilder.append("a : 'x' 'y'\n");
@@ -149,14 +150,14 @@ public class TestParseTrees extends BaseCppTest {
 	public void testNoViableAlt() throws Exception {
 		mkdir(tmpdir);
 
-		StringBuilder grammarBuilder = new StringBuilder(154);
+		StringBuilder grammarBuilder = new StringBuilder(155);
 		grammarBuilder.append("grammar T;\n");
 		grammarBuilder.append("s\n");
 		grammarBuilder.append("@init {\n");
-		grammarBuilder.append("_buildParseTrees = true\n");
+		grammarBuilder.append("_buildParseTrees = true;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("@after {\n");
-		grammarBuilder.append("std::cout << $r.ctx.toStringTree(recog=self) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << $r.ctx->toStringTree(this) << std::endl;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("  : r=a ;\n");
 		grammarBuilder.append("a : 'x' | 'y'\n");
@@ -181,14 +182,14 @@ public class TestParseTrees extends BaseCppTest {
 	public void testRuleRef() throws Exception {
 		mkdir(tmpdir);
 
-		StringBuilder grammarBuilder = new StringBuilder(148);
+		StringBuilder grammarBuilder = new StringBuilder(149);
 		grammarBuilder.append("grammar T;\n");
 		grammarBuilder.append("s\n");
 		grammarBuilder.append("@init {\n");
-		grammarBuilder.append("_buildParseTrees = true\n");
+		grammarBuilder.append("_buildParseTrees = true;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("@after {\n");
-		grammarBuilder.append("std::cout << $r.ctx.toStringTree(recog=self) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << $r.ctx->toStringTree(this) << std::endl;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("  : r=a ;\n");
 		grammarBuilder.append("a : b 'x'\n");
@@ -211,14 +212,14 @@ public class TestParseTrees extends BaseCppTest {
 	public void testSync() throws Exception {
 		mkdir(tmpdir);
 
-		StringBuilder grammarBuilder = new StringBuilder(155);
+		StringBuilder grammarBuilder = new StringBuilder(156);
 		grammarBuilder.append("grammar T;\n");
 		grammarBuilder.append("s\n");
 		grammarBuilder.append("@init {\n");
-		grammarBuilder.append("_buildParseTrees = true\n");
+		grammarBuilder.append("_buildParseTrees = true;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("@after {\n");
-		grammarBuilder.append("std::cout << $r.ctx.toStringTree(recog=self) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << $r.ctx->toStringTree(this) << std::endl;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("  : r=a ;\n");
 		grammarBuilder.append("a : 'x' 'y'* '!'\n");
@@ -242,14 +243,14 @@ public class TestParseTrees extends BaseCppTest {
 	public void testToken2() throws Exception {
 		mkdir(tmpdir);
 
-		StringBuilder grammarBuilder = new StringBuilder(137);
+		StringBuilder grammarBuilder = new StringBuilder(138);
 		grammarBuilder.append("grammar T;\n");
 		grammarBuilder.append("s\n");
 		grammarBuilder.append("@init {\n");
-		grammarBuilder.append("_buildParseTrees = true\n");
+		grammarBuilder.append("_buildParseTrees = true;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("@after {\n");
-		grammarBuilder.append("std::cout << $r.ctx.toStringTree(recog=self) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << $r.ctx->toStringTree(this) << std::endl;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("  : r=a ;\n");
 		grammarBuilder.append("a : 'x' 'y'\n");
@@ -270,18 +271,18 @@ public class TestParseTrees extends BaseCppTest {
 	public void testTokenAndRuleContextString() throws Exception {
 		mkdir(tmpdir);
 
-		StringBuilder grammarBuilder = new StringBuilder(193);
+		StringBuilder grammarBuilder = new StringBuilder(217);
 		grammarBuilder.append("grammar T;\n");
 		grammarBuilder.append("s\n");
 		grammarBuilder.append("@init {\n");
-		grammarBuilder.append("_buildParseTrees = true\n");
+		grammarBuilder.append("_buildParseTrees = true;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("@after {\n");
-		grammarBuilder.append("std::cout << $r.ctx.toStringTree(recog=self) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << $r.ctx->toStringTree(this) << std::endl;\n");
 		grammarBuilder.append("}\n");
 		grammarBuilder.append("  : r=a ;\n");
 		grammarBuilder.append("a : 'x' { \n");
-		grammarBuilder.append("std::cout << str_list(getRuleInvocationStack()) << \"\\n\";\n");
+		grammarBuilder.append("std::cout << Arrays::listToString(getRuleInvocationStack(), \", \") << std::endl;\n");
 		grammarBuilder.append("} ;");
 		String grammar = grammarBuilder.toString();
 
diff --git a/runtime/Cpp/runtime/src/atn/ParserATNSimulator.cpp b/runtime/Cpp/runtime/src/atn/ParserATNSimulator.cpp
index 48f23f1e6..6d27fc763 100755
--- a/runtime/Cpp/runtime/src/atn/ParserATNSimulator.cpp
+++ b/runtime/Cpp/runtime/src/atn/ParserATNSimulator.cpp
@@ -1037,7 +1037,7 @@ Ref<ATNConfig> ParserATNSimulator::precedenceTransition(Ref<ATNConfig> config, P
   if (debug) {
     std::cout << "PRED (collectPredicates=" << collectPredicates << ") " << pt->precedence << ">=_p" << ", ctx dependent=true" << std::endl;
     if (parser != nullptr) {
-      std::cout << "context surrounding pred is " << Arrays::listToString( parser->getRuleInvocationStack(), ", ") << std::endl;
+      std::cout << "context surrounding pred is " << Arrays::listToString(parser->getRuleInvocationStack(), ", ") << std::endl;
     }
   }
 
diff --git a/runtime/Cpp/runtime/src/support/Arrays.cpp b/runtime/Cpp/runtime/src/support/Arrays.cpp
index 49e51f3f5..2cd49e737 100644
--- a/runtime/Cpp/runtime/src/support/Arrays.cpp
+++ b/runtime/Cpp/runtime/src/support/Arrays.cpp
@@ -37,14 +37,17 @@ std::string Arrays::listToString(const std::vector<std::string> &list, const std
 {
   std::stringstream ss;
   bool firstEntry = true;
-  
+
+  ss << '[';
   for (auto &entry : list) {
     ss << entry;
-    if (!firstEntry)
+    if (firstEntry) {
       ss << separator;
-    firstEntry = false;
+      firstEntry = false;
+    }
   }
 
+  ss << ']';
   return ss.str();
 }