diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/csharp/CSharp.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/csharp/CSharp.test.stg
index 95e23c671..ca6182b47 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/csharp/CSharp.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/csharp/CSharp.test.stg
@@ -327,6 +327,19 @@ ParseTreeWalker walker = new ParseTreeWalker();
 walker.Walk(new LeafListener(), <s>);
 >>
 
+TreeNodeWithAltNumField(X) ::= <<
+@parser::members {
+public class MyRuleNode : ParserRuleContext {
+	public int altNum;
+	public MyRuleNode(ParserRuleContext parent, int invokingStateNumber): base(parent, invokingStateNumber)
+	{
+	}
+	public override int getAltNumber() { return altNum; }
+	public override void setAltNumber(int altNum) { this.altNum = altNum; }
+}
+}
+>>
+
 TokenGetterListener(X) ::= <<
 public class LeafListener : TBaseListener {
 	public override void ExitA(TParser.AContext ctx) {
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/java/Java.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/java/Java.test.stg
index 49a1ab461..45c6e1a63 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/java/Java.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/java/Java.test.stg
@@ -335,6 +335,19 @@ ParseTreeWalker walker = new ParseTreeWalker();
 walker.walk(new LeafListener(), <s>);
 >>
 
+TreeNodeWithAltNumField(X) ::= <<
+@parser::members {
+public static class MyRuleNode extends ParserRuleContext {
+	public int altNum;
+	public MyRuleNode(ParserRuleContext parent, int invokingStateNumber) {
+		super(parent, invokingStateNumber);
+	}
+	@Override public int getAltNumber() { return altNum; }
+	@Override public void setAltNumber(int altNum) { this.altNum = altNum; }
+}
+}
+>>
+
 TokenGetterListener(X) ::= <<
 public static class LeafListener extends TBaseListener {
 	public void exitA(TParser.AContext ctx) {
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/chrome/Chrome.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/chrome/Chrome.test.stg
index 56f70b081..649d3a127 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/chrome/Chrome.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/chrome/Chrome.test.stg
@@ -322,6 +322,20 @@ var walker = new antlr4.tree.ParseTreeWalker();
 walker.walk(new this.LeafListener(), <s>);
 >>
 
+TreeNodeWithAltNumField(X) ::= <<
+
+@parser::header {
+MyRuleNode = function(parent, invokingState) {
+	antlr4.ParserRuleContext.call(this, parent, invokingState);
+	this.altNum = 0;
+	return this;
+};
+
+MyRuleNode.prototype = Object.create(antlr4.ParserRuleContext.prototype);
+MyRuleNode.prototype.constructor = MyRuleNode;
+}
+>>
+
 TokenGetterListener(X) ::= <<
 this.LeafListener = function() {
     this.exitA = function(ctx) {
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/explorer/Explorer.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/explorer/Explorer.test.stg
index e85e5c8eb..7dba81947 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/explorer/Explorer.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/explorer/Explorer.test.stg
@@ -322,6 +322,20 @@ var walker = new antlr4.tree.ParseTreeWalker();
 walker.walk(new this.LeafListener(), <s>);
 >>
 
+TreeNodeWithAltNumField(X) ::= <<
+
+@parser::header {
+MyRuleNode = function(parent, invokingState) {
+	antlr4.ParserRuleContext.call(this, parent, invokingState);
+	this.altNum = 0;
+	return this;
+};
+
+MyRuleNode.prototype = Object.create(antlr4.ParserRuleContext.prototype);
+MyRuleNode.prototype.constructor = MyRuleNode;
+}
+>>
+
 TokenGetterListener(X) ::= <<
 this.LeafListener = function() {
     this.exitA = function(ctx) {
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/firefox/Firefox.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/firefox/Firefox.test.stg
index 892c2c924..f1a91fbea 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/firefox/Firefox.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/firefox/Firefox.test.stg
@@ -324,6 +324,20 @@ var walker = new antlr4.tree.ParseTreeWalker();
 walker.walk(new this.LeafListener(), <s>);
 >>
 
+TreeNodeWithAltNumField(X) ::= <<
+
+@parser::header {
+MyRuleNode = function(parent, invokingState) {
+	antlr4.ParserRuleContext.call(this, parent, invokingState);
+	this.altNum = 0;
+	return this;
+};
+
+MyRuleNode.prototype = Object.create(antlr4.ParserRuleContext.prototype);
+MyRuleNode.prototype.constructor = MyRuleNode;
+}
+>>
+
 TokenGetterListener(X) ::= <<
 this.LeafListener = function() {
     this.exitA = function(ctx) {
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/node/Node.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/node/Node.test.stg
index 2d37b028a..5bca3c134 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/node/Node.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/node/Node.test.stg
@@ -322,6 +322,24 @@ var walker = new antlr4.tree.ParseTreeWalker();
 walker.walk(new this.LeafListener(), <s>);
 >>
 
+TreeNodeWithAltNumField(X) ::= <<
+
+@parser::header {
+MyRuleNode = function(parent, invokingState) {
+	antlr4.ParserRuleContext.call(this, parent, invokingState);
+
+	this.altNum = 0;
+	return this;
+};
+
+MyRuleNode.prototype = Object.create(antlr4.ParserRuleContext.prototype);
+MyRuleNode.prototype.constructor = MyRuleNode;
+MyRuleNode.prototype.getAltNumber = function() { return this.altNum; }
+MyRuleNode.prototype.setAltNumber = function(altNumber) { this.altNum = altNumber; }
+
+}
+>>
+
 TokenGetterListener(X) ::= <<
 this.LeafListener = function() {
     this.exitA = function(ctx) {
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/safari/Safari.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/safari/Safari.test.stg
index a78e877aa..c05024066 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/safari/Safari.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/javascript/safari/Safari.test.stg
@@ -322,6 +322,21 @@ var walker = new antlr4.tree.ParseTreeWalker();
 walker.walk(new this.LeafListener(), <s>);
 >>
 
+TreeNodeWithAltNumField(X) ::= <<
+
+@parser::header {
+MyRuleNode = function(parent, invokingState) {
+	antlr4.ParserRuleContext.call(this, parent, invokingState);
+	this.altNum = 0;
+	return this;
+};
+
+MyRuleNode.prototype = Object.create(antlr4.ParserRuleContext.prototype);
+MyRuleNode.prototype.constructor = MyRuleNode;
+}
+>>
+
+
 TokenGetterListener(X) ::= <<
 this.LeafListener = function() {
     this.exitA = function(ctx) {
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/python2/Python2.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/python2/Python2.test.stg
index 401d28190..c86f4a646 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/python2/Python2.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/python2/Python2.test.stg
@@ -312,6 +312,19 @@ walker = ParseTreeWalker()
 walker.walk(TParser.LeafListener(), <s>)
 >>
 
+TreeNodeWithAltNumField(X) ::= <<
+@parser::members {
+class MyRuleNode(ParserRuleContext):
+    def __init__(self, parent = None, invokingStateNumber = None ):
+        super(<X>Parser.MyRuleNode, self).__init__(parent, invokingStateNumber)
+        self.altNum = 0;
+    def getAltNumber(self):
+        return self.altNum
+    def setAltNumber(self, altNum):
+        self.altNum = altNum
+}
+>>
+
 TokenGetterListener(X) ::= <<
 if __name__ is not None and "." in __name__:
     from .<X>Listener import <X>Listener
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/python3/Python3.test.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/python3/Python3.test.stg
index 21315805d..d57f6146e 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/python3/Python3.test.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/python3/Python3.test.stg
@@ -314,6 +314,19 @@ walker = ParseTreeWalker()
 walker.walk(TParser.LeafListener(), <s>)
 >>
 
+TreeNodeWithAltNumField(X) ::= <<
+@parser::members {
+class MyRuleNode(ParserRuleContext):
+    def __init__(self, parent:ParserRuleContext = None, invokingStateNumber:int = None ):
+        super(<X>Parser.MyRuleNode, self).__init__(parent, invokingStateNumber)
+        self.altNum = 0;
+    def getAltNumber(self):
+        return self.altNum
+    def setAltNumber(self, altNum):
+        self.altNum = altNum
+}
+>>
+
 TokenGetterListener(X) ::= <<
 class LeafListener(MockListener):
     def exitA(self, ctx):
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/templates/ParseTrees/AltNum.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/templates/ParseTrees/AltNum.stg
new file mode 100644
index 000000000..124112c1f
--- /dev/null
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/templates/ParseTrees/AltNum.stg
@@ -0,0 +1,40 @@
+TestType() ::= "Parser"
+
+Grammar ::= [
+	"T": {<grammar("T")>}
+]
+
+Input() ::= "xyz"
+
+Rule() ::= "s"
+
+Output() ::= <<
+(a:3 x (b:2 y) z)<\n>
+>>
+
+Errors() ::= ""
+
+grammar(grammarName) ::= <<
+grammar <grammarName>;
+
+options { contextSuperClass=MyRuleNode; }
+
+<TreeNodeWithAltNumField(X=grammarName)>
+
+
+s
+@init {
+<BuildParseTrees()>
+}
+@after {
+<ToStringTree("$r.ctx"):writeln()>
+}
+  : r=a ;
+
+a : 'f'
+  | 'g'
+  | 'x' b 'z'
+  ;
+b : 'e' {} | 'y'
+  ;
+>>
diff --git a/runtime-testsuite/resources/org/antlr/v4/test/runtime/templates/ParseTrees/Index.stg b/runtime-testsuite/resources/org/antlr/v4/test/runtime/templates/ParseTrees/Index.stg
index 5f71a146c..a8bc31d2d 100644
--- a/runtime-testsuite/resources/org/antlr/v4/test/runtime/templates/ParseTrees/Index.stg
+++ b/runtime-testsuite/resources/org/antlr/v4/test/runtime/templates/ParseTrees/Index.stg
@@ -6,5 +6,6 @@ TestTemplates ::= [
 	"RuleRef": [],
 	"ExtraToken": [],
 	"NoViableAlt": [],
-	"Sync": []
+	"Sync": [],
+	"AltNum": []
 ]
diff --git a/runtime-testsuite/test/org/antlr/v4/test/runtime/csharp/TestParseTrees.java b/runtime-testsuite/test/org/antlr/v4/test/runtime/csharp/TestParseTrees.java
index 4f6e1b322..3ff7bb4e1 100644
--- a/runtime-testsuite/test/org/antlr/v4/test/runtime/csharp/TestParseTrees.java
+++ b/runtime-testsuite/test/org/antlr/v4/test/runtime/csharp/TestParseTrees.java
@@ -2,7 +2,6 @@
 package org.antlr.v4.test.runtime.csharp;
 
 import org.junit.Test;
-import org.junit.Ignore;
 
 @SuppressWarnings("unused")
 public class TestParseTrees extends BaseTest {
@@ -52,6 +51,49 @@ public class TestParseTrees extends BaseTest {
 		assertEquals("(a y)\n", found);
 		assertNull(this.stderrDuringParse);
 
+	}
+	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
+	@Test
+	public void testAltNum() throws Exception {
+		mkdir(tmpdir);
+		StringBuilder grammarBuilder = new StringBuilder(547);
+		grammarBuilder.append("grammar T;\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("options { contextSuperClass=MyRuleNode; }\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("@parser::members {\n");
+		grammarBuilder.append("public class MyRuleNode : ParserRuleContext {\n");
+		grammarBuilder.append("	public int altNum;\n");
+		grammarBuilder.append("	public MyRuleNode(ParserRuleContext parent, int invokingStateNumber): base(parent, invokingStateNumber)\n");
+		grammarBuilder.append("	{\n");
+		grammarBuilder.append("	}\n");
+		grammarBuilder.append("	public override int getAltNumber() { return altNum; }\n");
+		grammarBuilder.append("	public override void setAltNumber(int altNum) { 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("this.BuildParseTree = true;\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("@after {\n");
+		grammarBuilder.append("Console.WriteLine($r.ctx.ToStringTree(this));\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("  : r=a ;\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("a : 'f'\n");
+		grammarBuilder.append("  | 'g'\n");
+		grammarBuilder.append("  | 'x' b 'z'\n");
+		grammarBuilder.append("  ;\n");
+		grammarBuilder.append("b : 'e' {} | 'y'\n");
+		grammarBuilder.append("  ;");
+		String grammar = grammarBuilder.toString();
+		String input ="xyz";
+		String found = execParser("T.g4", grammar, "TParser", "TLexer", "s", input, false);
+		assertEquals("(a:3 x (b:2 y) z)\n", found);
+		assertNull(this.stderrDuringParse);
+
 	}
 	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
 	@Test
diff --git a/runtime-testsuite/test/org/antlr/v4/test/runtime/java/TestParseTrees.java b/runtime-testsuite/test/org/antlr/v4/test/runtime/java/TestParseTrees.java
index 7067a2b53..7a0a944df 100644
--- a/runtime-testsuite/test/org/antlr/v4/test/runtime/java/TestParseTrees.java
+++ b/runtime-testsuite/test/org/antlr/v4/test/runtime/java/TestParseTrees.java
@@ -1,10 +1,10 @@
 /* This file is generated by TestGenerator, any edits will be overwritten by the next generation. */
 package org.antlr.v4.test.runtime.java;
 
-import org.junit.Ignore;
 import org.junit.Test;
 
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
 
 public class TestParseTrees extends BaseTest {
 
@@ -62,6 +62,53 @@ public class TestParseTrees extends BaseTest {
 
 	}
 
+	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
+	@Test
+	public void testAltNum() throws Exception {
+		mkdir(tmpdir);
+
+		StringBuilder grammarBuilder = new StringBuilder(562);
+		grammarBuilder.append("grammar T;\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("options { contextSuperClass=MyRuleNode; }\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("@parser::members {\n");
+		grammarBuilder.append("public static class MyRuleNode extends ParserRuleContext {\n");
+		grammarBuilder.append("	public int altNum;\n");
+		grammarBuilder.append("	public MyRuleNode(ParserRuleContext parent, int invokingStateNumber) {\n");
+		grammarBuilder.append("		super(parent, invokingStateNumber);\n");
+		grammarBuilder.append("	}\n");
+		grammarBuilder.append("	@Override public int getAltNumber() { return altNum; }\n");
+		grammarBuilder.append("	@Override public void setAltNumber(int altNum) { 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("setBuildParseTree(true);\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("@after {\n");
+		grammarBuilder.append("System.out.println($r.ctx.toStringTree(this));\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("  : r=a ;\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("a : 'f'\n");
+		grammarBuilder.append("  | 'g'\n");
+		grammarBuilder.append("  | 'x' b 'z'\n");
+		grammarBuilder.append("  ;\n");
+		grammarBuilder.append("b : 'e' {} | 'y'\n");
+		grammarBuilder.append("  ;");
+		String grammar = grammarBuilder.toString();
+
+
+		String input ="xyz";
+		String found = execParser("T.g4", grammar, "TParser", "TLexer", "s", input, false);
+		assertEquals("(a:3 x (b:2 y) z)\n", found);
+		assertNull(this.stderrDuringParse);
+
+	}
+
 	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
 	@Test
 	public void testExtraToken() throws Exception {
diff --git a/runtime-testsuite/test/org/antlr/v4/test/runtime/javascript/node/TestParseTrees.java b/runtime-testsuite/test/org/antlr/v4/test/runtime/javascript/node/TestParseTrees.java
index c1f9afa92..2dd5b992d 100644
--- a/runtime-testsuite/test/org/antlr/v4/test/runtime/javascript/node/TestParseTrees.java
+++ b/runtime-testsuite/test/org/antlr/v4/test/runtime/javascript/node/TestParseTrees.java
@@ -1,10 +1,10 @@
 /* This file is generated by TestGenerator, any edits will be overwritten by the next generation. */
 package org.antlr.v4.test.runtime.javascript.node;
 
-import org.junit.Ignore;
 import org.junit.Test;
 
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
 
 @SuppressWarnings("unused")
 public class TestParseTrees extends BaseTest {
@@ -58,6 +58,55 @@ public class TestParseTrees extends BaseTest {
 		assertEquals("(a y)\n", found);
 		assertNull(this.stderrDuringParse);
 
+	}
+	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
+	@Test
+	public void testAltNum() throws Exception {
+		mkdir(tmpdir);
+		StringBuilder grammarBuilder = new StringBuilder(663);
+		grammarBuilder.append("grammar T;\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("options { contextSuperClass=MyRuleNode; }\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("@parser::header {\n");
+		grammarBuilder.append("MyRuleNode = function(parent, invokingState) {\n");
+		grammarBuilder.append("	antlr4.ParserRuleContext.call(this, parent, invokingState);\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("	this.altNum = 0;\n");
+		grammarBuilder.append("	return this;\n");
+		grammarBuilder.append("};\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("MyRuleNode.prototype = Object.create(antlr4.ParserRuleContext.prototype);\n");
+		grammarBuilder.append("MyRuleNode.prototype.constructor = MyRuleNode;\n");
+		grammarBuilder.append("MyRuleNode.prototype.getAltNumber = function() { return this.altNum; }\n");
+		grammarBuilder.append("MyRuleNode.prototype.setAltNumber = function(altNumber) { this.altNum = altNumber; }\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("s\n");
+		grammarBuilder.append("@init {\n");
+		grammarBuilder.append("this.buildParseTrees = true;\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("@after {\n");
+		grammarBuilder.append("console.log($r.ctx.toStringTree(null, this));\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("  : r=a ;\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("a : 'f'\n");
+		grammarBuilder.append("  | 'g'\n");
+		grammarBuilder.append("  | 'x' b 'z'\n");
+		grammarBuilder.append("  ;\n");
+		grammarBuilder.append("b : 'e' {} | 'y'\n");
+		grammarBuilder.append("  ;");
+		String grammar = grammarBuilder.toString();
+		String input ="xyz";
+		String found = execParser("T.g4", grammar, "TParser", "TLexer",
+		                          "TListener", "TVisitor",
+		                          "s", input, false);
+		assertEquals("(a:3 x (b:2 y) z)\n", found);
+		assertNull(this.stderrDuringParse);
+
 	}
 	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
 	@Test
diff --git a/runtime-testsuite/test/org/antlr/v4/test/runtime/python2/TestParseTrees.java b/runtime-testsuite/test/org/antlr/v4/test/runtime/python2/TestParseTrees.java
index b94a2959e..da8e26f07 100644
--- a/runtime-testsuite/test/org/antlr/v4/test/runtime/python2/TestParseTrees.java
+++ b/runtime-testsuite/test/org/antlr/v4/test/runtime/python2/TestParseTrees.java
@@ -1,9 +1,10 @@
 /* This file is generated by TestGenerator, any edits will be overwritten by the next generation. */
 package org.antlr.v4.test.runtime.python2;
 
-import org.junit.Ignore;
 import org.junit.Test;
-import static org.junit.Assert.*;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
 
 @SuppressWarnings("unused")
 public class TestParseTrees extends BasePython2Test {
@@ -64,6 +65,54 @@ public class TestParseTrees extends BasePython2Test {
 
 	}
 
+	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
+	@Test
+	public void testAltNum() throws Exception {
+		mkdir(tmpdir);
+
+		StringBuilder grammarBuilder = new StringBuilder(562);
+		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("        self.altNum = 0;\n");
+		grammarBuilder.append("    def getAltNumber(self):\n");
+		grammarBuilder.append("        return self.altNum\n");
+		grammarBuilder.append("    def setAltNumber(self, altNum):\n");
+		grammarBuilder.append("        self.altNum = altNum\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("s\n");
+		grammarBuilder.append("@init {\n");
+		grammarBuilder.append("self._buildParseTrees = True\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("@after {\n");
+		grammarBuilder.append("print($r.ctx.toStringTree(recog=self))\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("  : r=a ;\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("a : 'f'\n");
+		grammarBuilder.append("  | 'g'\n");
+		grammarBuilder.append("  | 'x' b 'z'\n");
+		grammarBuilder.append("  ;\n");
+		grammarBuilder.append("b : 'e' {} | 'y'\n");
+		grammarBuilder.append("  ;");
+		String grammar = grammarBuilder.toString();
+
+
+		String input ="xyz";
+		String found = execParser("T.g4", grammar, "TParser", "TLexer", "TListener", "TVisitor", "s", input, false);
+
+		assertEquals("(a:3 x (b:2 y) z)\n", found);
+		assertNull(this.stderrDuringParse);
+
+	}
+
 	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
 	@Test
 	public void testExtraToken() throws Exception {
diff --git a/runtime-testsuite/test/org/antlr/v4/test/runtime/python3/BasePython3Test.java b/runtime-testsuite/test/org/antlr/v4/test/runtime/python3/BasePython3Test.java
index 8afe1c6da..8f55dabd3 100644
--- a/runtime-testsuite/test/org/antlr/v4/test/runtime/python3/BasePython3Test.java
+++ b/runtime-testsuite/test/org/antlr/v4/test/runtime/python3/BasePython3Test.java
@@ -41,7 +41,7 @@ public abstract class BasePython3Test extends BasePythonTest {
 
 	@Override
 	protected String getPythonExecutable() {
-		return "python3.5";
+		return "python3";
 	}
 
 	@Override
diff --git a/runtime-testsuite/test/org/antlr/v4/test/runtime/python3/TestParseTrees.java b/runtime-testsuite/test/org/antlr/v4/test/runtime/python3/TestParseTrees.java
index cb4d137e6..5d1b0da2d 100644
--- a/runtime-testsuite/test/org/antlr/v4/test/runtime/python3/TestParseTrees.java
+++ b/runtime-testsuite/test/org/antlr/v4/test/runtime/python3/TestParseTrees.java
@@ -1,9 +1,10 @@
 /* This file is generated by TestGenerator, any edits will be overwritten by the next generation. */
 package org.antlr.v4.test.runtime.python3;
 
-import org.junit.Ignore;
 import org.junit.Test;
-import static org.junit.Assert.*;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
 
 @SuppressWarnings("unused")
 public class TestParseTrees extends BasePython3Test {
@@ -64,6 +65,54 @@ public class TestParseTrees extends BasePython3Test {
 
 	}
 
+	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
+	@Test
+	public void testAltNum() throws Exception {
+		mkdir(tmpdir);
+
+		StringBuilder grammarBuilder = new StringBuilder(584);
+		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:ParserRuleContext = None, invokingStateNumber:int = None ):\n");
+		grammarBuilder.append("        super(TParser.MyRuleNode, self).__init__(parent, invokingStateNumber)\n");
+		grammarBuilder.append("        self.altNum = 0;\n");
+		grammarBuilder.append("    def getAltNumber(self):\n");
+		grammarBuilder.append("        return self.altNum\n");
+		grammarBuilder.append("    def setAltNumber(self, altNum):\n");
+		grammarBuilder.append("        self.altNum = altNum\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("s\n");
+		grammarBuilder.append("@init {\n");
+		grammarBuilder.append("self._buildParseTrees = True\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("@after {\n");
+		grammarBuilder.append("print($r.ctx.toStringTree(recog=self))\n");
+		grammarBuilder.append("}\n");
+		grammarBuilder.append("  : r=a ;\n");
+		grammarBuilder.append("\n");
+		grammarBuilder.append("a : 'f'\n");
+		grammarBuilder.append("  | 'g'\n");
+		grammarBuilder.append("  | 'x' b 'z'\n");
+		grammarBuilder.append("  ;\n");
+		grammarBuilder.append("b : 'e' {} | 'y'\n");
+		grammarBuilder.append("  ;");
+		String grammar = grammarBuilder.toString();
+
+
+		String input ="xyz";
+		String found = execParser("T.g4", grammar, "TParser", "TLexer", "TListener", "TVisitor", "s", input, false);
+
+		assertEquals("(a:3 x (b:2 y) z)\n", found);
+		assertNull(this.stderrDuringParse);
+
+	}
+
 	/* This file and method are generated by TestGenerator, any edits will be overwritten by the next generation. */
 	@Test
 	public void testExtraToken() throws Exception {
diff --git a/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/Parser.cs b/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/Parser.cs
index 8d13cf52f..9df0b4270 100644
--- a/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/Parser.cs
+++ b/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/Parser.cs
@@ -352,7 +352,7 @@ namespace Antlr4.Runtime
         /// for a newly constructed parser.
         /// </remarks>
         /// <returns>
-        /// 
+        ///
         /// <see langword="true"/>
         /// if a complete parse tree will be constructed while
         /// parsing, otherwise
@@ -378,14 +378,14 @@ namespace Antlr4.Runtime
         /// by default for a newly constructed parser.
         /// </remarks>
         /// <value>
-        /// 
+        ///
         /// <see langword="true"/>
         /// to trim the capacity of the
         /// <see cref="ParserRuleContext.children"/>
         /// list to its size after a rule is parsed.
         /// </value>
         /// <returns>
-        /// 
+        ///
         /// <see langword="true"/>
         /// if the
         /// <see cref="ParserRuleContext.children"/>
@@ -649,9 +649,9 @@ namespace Antlr4.Runtime
             }
         }
 
-        public override IIntStream InputStream 
+        public override IIntStream InputStream
 		{
-			get 
+			get
 			{
 				return _input;
 			}
@@ -659,11 +659,11 @@ namespace Antlr4.Runtime
 
 		public ITokenStream TokenStream
 		{
-			get 
+			get
 			{
 				return _input;
 			}
-			set 
+			set
 			{
 				this._input = null;
 				Reset ();
@@ -842,6 +842,7 @@ namespace Antlr4.Runtime
 
         public virtual void EnterOuterAlt(ParserRuleContext localctx, int altNum)
         {
+        	localctx.setAltNumber(altNum);
             // if we have new localctx, make sure we replace existing ctx
             // that is previous child of parse tree
             if (_buildParseTrees && _ctx != localctx)
@@ -1004,7 +1005,7 @@ namespace Antlr4.Runtime
         /// </summary>
         /// <param name="symbol">the symbol type to check</param>
         /// <returns>
-        /// 
+        ///
         /// <see langword="true"/>
         /// if
         /// <paramref name="symbol"/>
diff --git a/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/RuleContext.cs b/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/RuleContext.cs
index 6cb5fe96d..54a968ffa 100644
--- a/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/RuleContext.cs
+++ b/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/RuleContext.cs
@@ -30,6 +30,7 @@
 using System.Collections.Generic;
 using System.Text;
 using Antlr4.Runtime;
+using Antlr4.Runtime.Atn;
 using Antlr4.Runtime.Misc;
 using Antlr4.Runtime.Sharpen;
 using Antlr4.Runtime.Tree;
@@ -139,7 +140,7 @@ namespace Antlr4.Runtime
             {
                 return _parent;
             }
-			set 
+			set
 			{
 				_parent = value;
 			}
@@ -216,6 +217,23 @@ namespace Antlr4.Runtime
             }
         }
 
+	/* For rule associated with this parse tree internal node, return
+	 * the outer alternative number used to match the input. Default
+	 * implementation does not compute nor store this alt num. Create
+	 * a subclass of ParserRuleContext with backing field and set
+	 * option contextSuperClass.
+	 * to set it.
+	 */
+	public virtual int getAltNumber() { return Atn.ATN.InvalidAltNumber; }
+
+	/* Set the outer alternative number for this context node. Default
+	 * implementation does nothing to avoid backing field overhead for
+	 * trees that don't need it.  Create
+     * a subclass of ParserRuleContext with backing field and set
+     * option contextSuperClass.
+	 */
+	public virtual void setAltNumber(int altNumber) { }
+
         public virtual IParseTree GetChild(int i)
         {
             return null;
diff --git a/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/Tree/Trees.cs b/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/Tree/Trees.cs
index bb70f7329..c77866920 100644
--- a/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/Tree/Trees.cs
+++ b/runtime/CSharp/runtime/CSharp/Antlr4.Runtime/Tree/Trees.cs
@@ -30,6 +30,7 @@
 using System.Collections.Generic;
 using System.Text;
 using Antlr4.Runtime;
+using Antlr4.Runtime.Atn;
 using Antlr4.Runtime.Misc;
 using Antlr4.Runtime.Sharpen;
 using Antlr4.Runtime.Tree;
@@ -111,10 +112,14 @@ namespace Antlr4.Runtime.Tree
         {
             if (ruleNames != null)
             {
-                if (t is IRuleNode)
+                if (t is RuleContext)
                 {
-                    int ruleIndex = ((IRuleNode)t).RuleContext.RuleIndex;
+                    int ruleIndex = ((RuleContext)t).RuleIndex;
                     string ruleName = ruleNames[ruleIndex];
+					int altNumber = ((RuleContext)t).getAltNumber();
+					if ( altNumber!=Atn.ATN.InvalidAltNumber ) {
+						return ruleName+":"+altNumber;
+					}
                     return ruleName;
                 }
                 else
diff --git a/runtime/Java/src/org/antlr/v4/runtime/RuleContextWithAltNum.java b/runtime/Java/src/org/antlr/v4/runtime/RuleContextWithAltNum.java
new file mode 100644
index 000000000..0cd5b11a6
--- /dev/null
+++ b/runtime/Java/src/org/antlr/v4/runtime/RuleContextWithAltNum.java
@@ -0,0 +1,20 @@
+package org.antlr.v4.runtime;
+
+/** A handy class for use with
+ *
+ *  options {contextSuperClass=org.antlr.v4.runtime.RuleContextWithAltNum;}
+ *
+ *  that provides a backing field / impl for the outer alternative number
+ *  matched for an internal parse tree node.
+ *
+ *  I'm only putting into Java runtime as I'm certain I'm the only one that
+ *  will really every use this.
+ */
+public class RuleContextWithAltNum extends ParserRuleContext {
+	public int altNum;
+	public RuleContextWithAltNum(ParserRuleContext parent, int invokingStateNumber) {
+		super(parent, invokingStateNumber);
+	}
+	@Override public int getAltNumber() { return altNum; }
+	@Override public void setAltNumber(int altNum) { this.altNum = altNum; }
+}
diff --git a/runtime/Java/src/org/antlr/v4/runtime/tree/Trees.java b/runtime/Java/src/org/antlr/v4/runtime/tree/Trees.java
index c58ee3dbe..3cb86683b 100644
--- a/runtime/Java/src/org/antlr/v4/runtime/tree/Trees.java
+++ b/runtime/Java/src/org/antlr/v4/runtime/tree/Trees.java
@@ -33,7 +33,9 @@ package org.antlr.v4.runtime.tree;
 import org.antlr.v4.runtime.CommonToken;
 import org.antlr.v4.runtime.Parser;
 import org.antlr.v4.runtime.ParserRuleContext;
+import org.antlr.v4.runtime.RuleContext;
 import org.antlr.v4.runtime.Token;
+import org.antlr.v4.runtime.atn.ATN;
 import org.antlr.v4.runtime.misc.Interval;
 import org.antlr.v4.runtime.misc.Predicate;
 import org.antlr.v4.runtime.misc.Utils;
@@ -91,9 +93,13 @@ public class Trees {
 
 	public static String getNodeText(Tree t, List<String> ruleNames) {
 		if ( ruleNames!=null ) {
-			if ( t instanceof RuleNode ) {
-				int ruleIndex = ((RuleNode)t).getRuleContext().getRuleIndex();
+			if ( t instanceof RuleContext ) {
+				int ruleIndex = ((RuleContext)t).getRuleContext().getRuleIndex();
 				String ruleName = ruleNames.get(ruleIndex);
+				int altNumber = ((RuleContext) t).getAltNumber();
+				if ( altNumber!=ATN.INVALID_ALT_NUMBER ) {
+					return ruleName+":"+altNumber;
+				}
 				return ruleName;
 			}
 			else if ( t instanceof ErrorNode) {
diff --git a/runtime/JavaScript/src/antlr4/Parser.js b/runtime/JavaScript/src/antlr4/Parser.js
index 38e66dc74..1ec5cc014 100644
--- a/runtime/JavaScript/src/antlr4/Parser.js
+++ b/runtime/JavaScript/src/antlr4/Parser.js
@@ -451,6 +451,7 @@ Parser.prototype.exitRule = function() {
 };
 
 Parser.prototype.enterOuterAlt = function(localctx, altNum) {
+   	localctx.setAltNumber(altNum);
 	// if we have new localctx, make sure we replace existing ctx
 	// that is previous child of parse tree
 	if (this.buildParseTrees && this._ctx !== localctx) {
diff --git a/runtime/JavaScript/src/antlr4/RuleContext.js b/runtime/JavaScript/src/antlr4/RuleContext.js
index 7299357b9..c3631bab6 100644
--- a/runtime/JavaScript/src/antlr4/RuleContext.js
+++ b/runtime/JavaScript/src/antlr4/RuleContext.js
@@ -51,6 +51,7 @@
 
 var RuleNode = require('./tree/Tree').RuleNode;
 var INVALID_INTERVAL = require('./tree/Tree').INVALID_INTERVAL;
+var INVALID_ALT_NUMBER = require('./atn/ATN').INVALID_ALT_NUMBER;
 
 function RuleContext(parent, invokingState) {
 	RuleNode.call(this);
@@ -113,6 +114,21 @@ RuleContext.prototype.getText = function() {
 	}
 };
 
+// For rule associated with this parse tree internal node, return
+// the outer alternative number used to match the input. Default
+// implementation does not compute nor store this alt num. Create
+// a subclass of ParserRuleContext with backing field and set
+// option contextSuperClass.
+// to set it.
+RuleContext.prototype.getAltNumber = function() { return INVALID_ALT_NUMBER; }
+
+// Set the outer alternative number for this context node. Default
+// implementation does nothing to avoid backing field overhead for
+// trees that don't need it.  Create
+// a subclass of ParserRuleContext with backing field and set
+// option contextSuperClass.
+RuleContext.prototype.setAltNumber = function(altNumber) { }
+
 RuleContext.prototype.getChild = function(i) {
 	return null;
 };
diff --git a/runtime/JavaScript/src/antlr4/tree/Trees.js b/runtime/JavaScript/src/antlr4/tree/Trees.js
index 38a039b2e..d20258e73 100644
--- a/runtime/JavaScript/src/antlr4/tree/Trees.js
+++ b/runtime/JavaScript/src/antlr4/tree/Trees.js
@@ -34,6 +34,8 @@ var RuleNode = require('./Tree').RuleNode;
 var ErrorNode = require('./Tree').ErrorNode;
 var TerminalNode = require('./Tree').TerminalNode;
 var ParserRuleContext = require('./../ParserRuleContext').ParserRuleContext;
+var RuleContext = require('./../RuleContext').RuleContext;
+var INVALID_ALT_NUMBER = require('./../atn/ATN').INVALID_ALT_NUMBER;
 
 
 /** A set of utility routines useful for all kinds of ANTLR trees. */
@@ -75,8 +77,12 @@ Trees.getNodeText = function(t, ruleNames, recog) {
         ruleNames = recog.ruleNames;
     }
     if(ruleNames!==null) {
-       if (t instanceof RuleNode) {
-           return ruleNames[t.getRuleContext().ruleIndex];
+       if (t instanceof RuleContext) {
+           var altNumber = t.getAltNumber();
+           if ( altNumber!=INVALID_ALT_NUMBER ) {
+               return ruleNames[t.ruleIndex]+":"+altNumber;
+           }
+           return ruleNames[t.ruleIndex];
        } else if ( t instanceof ErrorNode) {
            return t.toString();
        } else if(t instanceof TerminalNode) {
@@ -115,7 +121,7 @@ Trees.getAncestors = function(t) {
     }
     return ancestors;
 };
-   
+
 Trees.findAllTokenNodes = function(t, ttype) {
     return Trees.findAllNodes(t, ttype, true);
 };
diff --git a/runtime/Python2/setup.py b/runtime/Python2/setup.py
index 42dbc86b5..b4815753e 100644
--- a/runtime/Python2/setup.py
+++ b/runtime/Python2/setup.py
@@ -2,12 +2,12 @@ from distutils.core import setup
 
 setup(
     name='antlr4-python2-runtime',
-    version='4.5.2.1',
+    version='4.5.3',
     packages=['antlr4', 'antlr4.atn', 'antlr4.dfa', 'antlr4.tree', 'antlr4.error', 'antlr4.xpath'],
     package_dir={'': 'src'},
     url='http://www.antlr.org',
     license='BSD',
     author='Eric Vergnaud, Terence Parr, Sam Harwell',
     author_email='eric.vergnaud@wanadoo.fr',
-    description='ANTLR 4.5.2.1 runtime for Python 2.7.6'
+    description='ANTLR 4.5.3 runtime for Python 2.7.6'
 )
diff --git a/runtime/Python2/src/antlr4/Parser.py b/runtime/Python2/src/antlr4/Parser.py
index 47e58d073..0439df2c4 100644
--- a/runtime/Python2/src/antlr4/Parser.py
+++ b/runtime/Python2/src/antlr4/Parser.py
@@ -38,7 +38,7 @@ from antlr4.tree.ParseTreePatternMatcher import ParseTreePatternMatcher
 from antlr4.tree.Tree import ParseTreeListener
 
 class TraceListener(ParseTreeListener):
-    
+
     def __init__(self, parser):
         self._parser = parser
 
@@ -152,7 +152,7 @@ class Parser (Recognizer):
     # @throws RecognitionException if the current input symbol did not match
     # a wildcard and the error strategy could not recover from the mismatched
     # symbol
-    
+
     def matchWildcard(self):
         t = self.getCurrentToken()
         if t.type > 0:
@@ -382,6 +382,7 @@ class Parser (Recognizer):
         self._ctx = self._ctx.parentCtx
 
     def enterOuterAlt(self, localctx, altNum):
+        localctx.setAltNumber(altNum)
         # if we have new localctx, make sure we replace existing ctx
         # that is previous child of parse tree
         if self.buildParseTrees and self._ctx != localctx:
diff --git a/runtime/Python2/src/antlr4/RuleContext.py b/runtime/Python2/src/antlr4/RuleContext.py
index 26e7c90c3..517f873d6 100644
--- a/runtime/Python2/src/antlr4/RuleContext.py
+++ b/runtime/Python2/src/antlr4/RuleContext.py
@@ -52,6 +52,7 @@
 from io import StringIO
 from antlr4.tree.Tree import RuleNode, INVALID_INTERVAL
 from antlr4.tree.Trees import Trees
+from antlr4.atn.ATN import ATN
 
 class RuleContext(RuleNode):
 
@@ -109,6 +110,23 @@ class RuleContext(RuleNode):
     def getRuleIndex(self):
         return -1
 
+	# For rule associated with this parse tree internal node, return
+	# the outer alternative number used to match the input. Default
+	# implementation does not compute nor store this alt num. Create
+	# a subclass of ParserRuleContext with backing field and set
+	# option contextSuperClass.
+	# to set it.
+    def getAltNumber(self):
+        return ATN.INVALID_ALT_NUMBER
+
+	# Set the outer alternative number for this context node. Default
+	# implementation does nothing to avoid backing field overhead for
+	# trees that don't need it.  Create
+	# a subclass of ParserRuleContext with backing field and set
+	# option contextSuperClass.
+    def setAltNumber(self, altNumber):
+        pass
+
     def getChild(self, i):
         return None
 
diff --git a/runtime/Python2/src/antlr4/tree/Trees.py b/runtime/Python2/src/antlr4/tree/Trees.py
index 61722faa9..d48f4a904 100644
--- a/runtime/Python2/src/antlr4/tree/Trees.py
+++ b/runtime/Python2/src/antlr4/tree/Trees.py
@@ -32,6 +32,8 @@
 
 # A set of utility routines useful for all kinds of ANTLR trees.#
 from io import StringIO
+import antlr4
+from antlr4.atn.ATN import ATN
 from antlr4.Token import Token
 from antlr4.Utils import escapeWhitespace
 from antlr4.tree.Tree import RuleNode, ErrorNode, TerminalNode
@@ -65,7 +67,9 @@ class Trees(object):
             ruleNames = recog.ruleNames
         if ruleNames is not None:
             if isinstance(t, RuleNode):
-                return ruleNames[t.getRuleContext().getRuleIndex()]
+                if t.getAltNumber()!=ATN.INVALID_ALT_NUMBER:
+                    return ruleNames[t.getRuleIndex()]+":"+str(t.getAltNumber())
+                return ruleNames[t.getRuleIndex()]
             elif isinstance( t, ErrorNode):
                 return unicode(t)
             elif isinstance(t, TerminalNode):
diff --git a/runtime/Python3/setup.py b/runtime/Python3/setup.py
index 65cdd8d27..2de08f223 100644
--- a/runtime/Python3/setup.py
+++ b/runtime/Python3/setup.py
@@ -2,12 +2,12 @@ from distutils.core import setup
 
 setup(
     name='antlr4-python3-runtime',
-    version='4.5.2.1',
+    version='4.5.3',
     packages=['antlr4', 'antlr4.atn', 'antlr4.dfa', 'antlr4.tree', 'antlr4.error', 'antlr4.xpath'],
     package_dir={'': 'src'},
     url='http://www.antlr.org',
     license='BSD',
     author='Eric Vergnaud, Terence Parr, Sam Harwell',
     author_email='eric.vergnaud@wanadoo.fr',
-    description='ANTLR 4.5.2.1 runtime for Python 3.4.0'
+    description='ANTLR 4.5.3 runtime for Python 3.4.0'
 )
diff --git a/runtime/Python3/src/antlr4/Parser.py b/runtime/Python3/src/antlr4/Parser.py
index 224cd4024..0d6824b20 100644
--- a/runtime/Python3/src/antlr4/Parser.py
+++ b/runtime/Python3/src/antlr4/Parser.py
@@ -159,7 +159,7 @@ class Parser (Recognizer):
     # @throws RecognitionException if the current input symbol did not match
     # a wildcard and the error strategy could not recover from the mismatched
     # symbol
-    
+
     def matchWildcard(self):
         t = self.getCurrentToken()
         if t.type > 0:
@@ -389,6 +389,7 @@ class Parser (Recognizer):
         self._ctx = self._ctx.parentCtx
 
     def enterOuterAlt(self, localctx:ParserRuleContext, altNum:int):
+        localctx.setAltNumber(altNum)
         # if we have new localctx, make sure we replace existing ctx
         # that is previous child of parse tree
         if self.buildParseTrees and self._ctx != localctx:
diff --git a/runtime/Python3/src/antlr4/RuleContext.py b/runtime/Python3/src/antlr4/RuleContext.py
index 496235715..c8f5ae053 100644
--- a/runtime/Python3/src/antlr4/RuleContext.py
+++ b/runtime/Python3/src/antlr4/RuleContext.py
@@ -113,6 +113,23 @@ class RuleContext(RuleNode):
     def getRuleIndex(self):
         return -1
 
+    # For rule associated with this parse tree internal node, return
+    # the outer alternative number used to match the input. Default
+    # implementation does not compute nor store this alt num. Create
+    # a subclass of ParserRuleContext with backing field and set
+    # option contextSuperClass.
+    # to set it.
+    def getAltNumber(self):
+        return 0 # should use ATN.INVALID_ALT_NUMBER but won't compile
+
+    # Set the outer alternative number for this context node. Default
+    # implementation does nothing to avoid backing field overhead for
+    # trees that don't need it.  Create
+    # a subclass of ParserRuleContext with backing field and set
+    # option contextSuperClass.
+    def setAltNumber(self, altNumber:int):
+        pass
+
     def getChild(self, i:int):
         return None
 
diff --git a/runtime/Python3/src/antlr4/tree/Trees.py b/runtime/Python3/src/antlr4/tree/Trees.py
index 234034586..101df6d9a 100644
--- a/runtime/Python3/src/antlr4/tree/Trees.py
+++ b/runtime/Python3/src/antlr4/tree/Trees.py
@@ -68,7 +68,9 @@ class Trees(object):
             ruleNames = recog.ruleNames
         if ruleNames is not None:
             if isinstance(t, RuleNode):
-                return ruleNames[t.getRuleContext().getRuleIndex()]
+                if t.getAltNumber()!=0: # should use ATN.INVALID_ALT_NUMBER but won't compile
+                    return ruleNames[t.getRuleIndex()]+":"+str(t.getAltNumber())
+                return ruleNames[t.getRuleIndex()]
             elif isinstance( t, ErrorNode):
                 return str(t)
             elif isinstance(t, TerminalNode):
diff --git a/tool-testsuite/test/org/antlr/v4/test/tool/InterpreterTreeTextProvider.java b/tool-testsuite/test/org/antlr/v4/test/tool/InterpreterTreeTextProvider.java
index 1a555c4ed..bff84ae17 100644
--- a/tool-testsuite/test/org/antlr/v4/test/tool/InterpreterTreeTextProvider.java
+++ b/tool-testsuite/test/org/antlr/v4/test/tool/InterpreterTreeTextProvider.java
@@ -1,10 +1,9 @@
 package org.antlr.v4.test.tool;
 
+import org.antlr.v4.gui.TreeTextProvider;
 import org.antlr.v4.runtime.tree.ErrorNode;
 import org.antlr.v4.runtime.tree.Tree;
 import org.antlr.v4.runtime.tree.Trees;
-import org.antlr.v4.gui.TreeTextProvider;
-import org.antlr.v4.tool.GrammarInterpreterRuleContext;
 
 import java.util.Arrays;
 import java.util.List;
@@ -17,10 +16,6 @@ public class InterpreterTreeTextProvider implements TreeTextProvider {
 	public String getText(Tree node) {
 		if ( node==null ) return "null";
 		String nodeText = Trees.getNodeText(node, ruleNames);
-		if ( node instanceof GrammarInterpreterRuleContext) {
-			GrammarInterpreterRuleContext ctx = (GrammarInterpreterRuleContext) node;
-			return nodeText+":"+ctx.getOuterAltNum();
-		}
 		if ( node instanceof ErrorNode) {
 			return "<error "+nodeText+">";
 		}
diff --git a/tool/resources/org/antlr/v4/tool/templates/codegen/CSharp/CSharp.stg b/tool/resources/org/antlr/v4/tool/templates/codegen/CSharp/CSharp.stg
index 0617385b1..6d5710922 100644
--- a/tool/resources/org/antlr/v4/tool/templates/codegen/CSharp/CSharp.stg
+++ b/tool/resources/org/antlr/v4/tool/templates/codegen/CSharp/CSharp.stg
@@ -30,7 +30,7 @@
 
 // args must be <object-model-object>, <fields-resulting-in-STs>
 
-ParserFile(file, parser, namedActions) ::= <<
+ParserFile(file, parser, namedActions, contextSuperClass) ::= <<
 <fileHeader(file.grammarFileName, file.ANTLRVersion)>
 <if(file.genPackage)>
 namespace <file.genPackage> {
@@ -839,7 +839,7 @@ CaptureNextTokenType(d) ::= "<d.varName> = TokenStream.La(1);"
 
 StructDecl(struct,ctorAttrs,attrs,getters,dispatchMethods,interfaces,extensionMembers,
            superClass={ParserRuleContext}) ::= <<
-public partial class <struct.name> : <superClass><if(interfaces)>, <interfaces; separator=", "><endif> {
+public partial class <struct.name> : <if(contextSuperClass)><contextSuperClass><else>ParserRuleContext<endif><if(interfaces)>, <interfaces; separator=", "><endif> {
 	<attrs:{a | public <a>;}; separator="\n">
 	<getters:{g | <g>}; separator="\n">
 	<if(ctorAttrs)>public <struct.name>(ParserRuleContext parent, int invokingState) : base(parent, invokingState) { }<endif>
diff --git a/tool/resources/org/antlr/v4/tool/templates/codegen/Java/Java.stg b/tool/resources/org/antlr/v4/tool/templates/codegen/Java/Java.stg
index ea3dba1de..af925be25 100644
--- a/tool/resources/org/antlr/v4/tool/templates/codegen/Java/Java.stg
+++ b/tool/resources/org/antlr/v4/tool/templates/codegen/Java/Java.stg
@@ -42,7 +42,7 @@ javaTypeInitMap ::= [
 
 // args must be <object-model-object>, <fields-resulting-in-STs>
 
-ParserFile(file, parser, namedActions) ::= <<
+ParserFile(file, parser, namedActions, contextSuperClass) ::= <<
 <fileHeader(file.grammarFileName, file.ANTLRVersion)>
 <if(file.genPackage)>
 package <file.genPackage>;
@@ -765,8 +765,9 @@ ListLabelName(label)		  ::= "<label>"
 CaptureNextToken(d) ::= "<d.varName> = _input.LT(1);"
 CaptureNextTokenType(d) ::= "<d.varName> = _input.LA(1);"
 
-StructDecl(struct,ctorAttrs,attrs,getters,dispatchMethods,interfaces,extensionMembers) ::= <<
-public static class <struct.name> extends ParserRuleContext <if(interfaces)> implements <interfaces; separator=", "><endif> {
+StructDecl(struct,ctorAttrs,attrs,getters,dispatchMethods,interfaces,extensionMembers)
+	::= <<
+public static class <struct.name> extends <if(contextSuperClass)><contextSuperClass><else>ParserRuleContext<endif><if(interfaces)> implements <interfaces; separator=", "><endif> {
 	<attrs:{a | public <a>;}; separator="\n">
 	<getters:{g | <g>}; separator="\n">
 	<if(ctorAttrs)>public <struct.name>(ParserRuleContext parent, int invokingState) { super(parent, invokingState); }<endif>
diff --git a/tool/resources/org/antlr/v4/tool/templates/codegen/JavaScript/JavaScript.stg b/tool/resources/org/antlr/v4/tool/templates/codegen/JavaScript/JavaScript.stg
index b015c0b5b..f8101b2da 100644
--- a/tool/resources/org/antlr/v4/tool/templates/codegen/JavaScript/JavaScript.stg
+++ b/tool/resources/org/antlr/v4/tool/templates/codegen/JavaScript/JavaScript.stg
@@ -46,7 +46,7 @@ pythonTypeInitMap ::= [
 
 // args must be <object-model-object>, <fields-resulting-in-STs>
 
-ParserFile(file, parser, namedActions) ::= <<
+ParserFile(file, parser, namedActions, contextSuperClass) ::= <<
 <fileHeader(file.grammarFileName, file.ANTLRVersion)>
 var antlr4 = require('antlr4/index');
 <if(file.genListener)>
@@ -671,8 +671,7 @@ ListLabelName(label)		  ::= "<label>"
 CaptureNextToken(d) ::= "<d.varName> = self._input.LT(1)"
 CaptureNextTokenType(d) ::= "<d.varName> = this._input.LA(1);"
 
-StructDecl(struct,ctorAttrs,attrs,getters,dispatchMethods,interfaces,extensionMembers,
-           superClass={antlr4.ParserRuleContext}) ::= <<
+StructDecl(struct,ctorAttrs,attrs,getters,dispatchMethods,interfaces,extensionMembers) ::= <<
 function <struct.name>(parser, parent, invokingState<struct.ctorAttrs:{a | , <a.name>}>) {
 	if(parent===undefined) {
 	    parent = null;
@@ -680,7 +679,7 @@ function <struct.name>(parser, parent, invokingState<struct.ctorAttrs:{a | , <a.
 	if(invokingState===undefined || invokingState===null) {
 		invokingState = -1;
 	}
-	<superClass>.call(this, parent, invokingState);
+	<if(contextSuperClass)><contextSuperClass><else>antlr4.ParserRuleContext<endif>.call(this, parent, invokingState);
     this.parser = parser;
     this.ruleIndex = <parser.name>.RULE_<struct.derivedFromName>;
     <attrs:{a | <a>}; separator="\n">
@@ -688,14 +687,14 @@ function <struct.name>(parser, parent, invokingState<struct.ctorAttrs:{a | , <a.
     return this;
 }
 
-<struct.name>.prototype = Object.create(<superClass>.prototype);
+<struct.name>.prototype = Object.create(<if(contextSuperClass)><contextSuperClass><else>antlr4.ParserRuleContext<endif>.prototype);
 <struct.name>.prototype.constructor = <struct.name>;
 
 <getters:{g | <struct.name>.prototype.<g>}; separator="\n\n">
 
 <if(struct.provideCopyFrom)> <! don't need copy unless we have subclasses !>
 <struct.name>.prototype.copyFrom = function(ctx) {
-    <superClass>.prototype.copyFrom.call(this, ctx);
+    <if(contextSuperClass)><contextSuperClass><else>antlr4.ParserRuleContext<endif>.prototype.copyFrom.call(this, ctx);
     <struct.attrs:{a | this.<a.name> = ctx.<a.name>;}; separator="\n">
 };
 <endif>
diff --git a/tool/resources/org/antlr/v4/tool/templates/codegen/Python2/Python2.stg b/tool/resources/org/antlr/v4/tool/templates/codegen/Python2/Python2.stg
index 66d84e6a0..c4ab7cccd 100644
--- a/tool/resources/org/antlr/v4/tool/templates/codegen/Python2/Python2.stg
+++ b/tool/resources/org/antlr/v4/tool/templates/codegen/Python2/Python2.stg
@@ -46,7 +46,7 @@ pythonTypeInitMap ::= [
 
 // args must be <object-model-object>, <fields-resulting-in-STs>
 
-ParserFile(file, parser, namedActions) ::= <<
+ParserFile(file, parser, namedActions, contextSuperClass) ::= <<
 <fileHeader(file.grammarFileName, file.ANTLRVersion)>
 # encoding: utf-8
 from __future__ import print_function
@@ -630,9 +630,8 @@ ListLabelName(label)		  ::= "<label>"
 CaptureNextToken(d) ::= "<d.varName> = self._input.LT(1)"
 CaptureNextTokenType(d) ::= "<d.varName> = self._input.LA(1)"
 
-StructDecl(struct,ctorAttrs,attrs,getters,dispatchMethods,interfaces,extensionMembers,
-           superClass={ParserRuleContext}) ::= <<
-class <struct.name>(<superClass>):
+StructDecl(struct,ctorAttrs,attrs,getters,dispatchMethods,interfaces,extensionMembers) ::= <<
+class <struct.name>(<if(contextSuperClass)><contextSuperClass><else>ParserRuleContext<endif>):
 
     def __init__(self, parser, parent=None, invokingState=-1<struct.ctorAttrs:{a | , <a.name>=None}>):
         super(<parser.name>.<struct.name>, self).__init__(parent, invokingState)
diff --git a/tool/resources/org/antlr/v4/tool/templates/codegen/Python3/Python3.stg b/tool/resources/org/antlr/v4/tool/templates/codegen/Python3/Python3.stg
index 515cf65f2..c3410795b 100644
--- a/tool/resources/org/antlr/v4/tool/templates/codegen/Python3/Python3.stg
+++ b/tool/resources/org/antlr/v4/tool/templates/codegen/Python3/Python3.stg
@@ -46,7 +46,7 @@ pythonTypeInitMap ::= [
 
 // args must be <object-model-object>, <fields-resulting-in-STs>
 
-ParserFile(file, parser, namedActions) ::= <<
+ParserFile(file, parser, namedActions, contextSuperClass) ::= <<
 <fileHeader(file.grammarFileName, file.ANTLRVersion)>
 # encoding: utf-8
 from antlr4 import *
@@ -638,9 +638,8 @@ ListLabelName(label)		  ::= "<label>"
 CaptureNextToken(d) ::= "<d.varName> = self._input.LT(1)"
 CaptureNextTokenType(d) ::= "<d.varName> = self._input.LA(1)"
 
-StructDecl(struct,ctorAttrs,attrs,getters,dispatchMethods,interfaces,extensionMembers,
-           superClass={ParserRuleContext}) ::= <<
-class <struct.name>(<superClass>):
+StructDecl(struct,ctorAttrs,attrs,getters,dispatchMethods,interfaces,extensionMembers) ::= <<
+class <struct.name>(<if(contextSuperClass)><contextSuperClass><else>ParserRuleContext<endif>):
 
     def __init__(self, parser, parent:ParserRuleContext=None, invokingState:int=-1<struct.ctorAttrs:{a | , <a.name><if(a.type)>:<a.type><endif>=None}>):
         super().__init__(parent, invokingState)
diff --git a/tool/src/org/antlr/v4/codegen/model/ParserFile.java b/tool/src/org/antlr/v4/codegen/model/ParserFile.java
index e2ce0525e..808d4f92b 100644
--- a/tool/src/org/antlr/v4/codegen/model/ParserFile.java
+++ b/tool/src/org/antlr/v4/codegen/model/ParserFile.java
@@ -63,8 +63,8 @@ public class ParserFile extends OutputFile {
 		genVisitor = g.tool.gen_visitor;
 		grammarName = g.name;
 
-		if (g.getOptionString("superClass") != null) {
-			contextSuperClass = new ActionText(null, g.getOptionString("superClass"));
+		if (g.getOptionString("contextSuperClass") != null) {
+			contextSuperClass = new ActionText(null, g.getOptionString("contextSuperClass"));
 		}
 	}
 }
diff --git a/tool/src/org/antlr/v4/tool/GrammarInterpreterRuleContext.java b/tool/src/org/antlr/v4/tool/GrammarInterpreterRuleContext.java
index 8457a6afb..936b8dca2 100644
--- a/tool/src/org/antlr/v4/tool/GrammarInterpreterRuleContext.java
+++ b/tool/src/org/antlr/v4/tool/GrammarInterpreterRuleContext.java
@@ -54,4 +54,15 @@ public class GrammarInterpreterRuleContext extends InterpreterRuleContext {
 	public void setOuterAltNum(int outerAltNum) {
 		this.outerAltNum = outerAltNum;
 	}
+
+	@Override
+	public int getAltNumber() {
+		// override here and called old functionality; makes it backward compatible vs changing names
+		return getOuterAltNum();
+	}
+
+	@Override
+	public void setAltNumber(int altNumber) {
+		setOuterAltNum(altNumber);
+	}
 }