Ensure file paths passed to STGroup[File] are absolute

- gracefully handle grammars without source fileNames

pom.xml

@@ -11,7 +11,7 @@
 		<artifactId>oss-parent</artifactId>
 		<version>9</version>
 	</parent>
-	<groupId>org.antlr</groupId>
+	<groupId>solussd</groupId>
 	<artifactId>antlr4-master</artifactId>
 	<version>4.7.2-SNAPSHOT</version>
 	<packaging>pom</packaging>

runtime/Java/pom.xml

@@ -7,7 +7,7 @@
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 	<parent>
-		<groupId>org.antlr</groupId>
+		<groupId>solussd</groupId>
 		<artifactId>antlr4-master</artifactId>
 		<version>4.7.2-SNAPSHOT</version>
 		<relativePath>../../pom.xml</relativePath>

tool/pom.xml

@@ -7,7 +7,7 @@
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 	<parent>
-		<groupId>org.antlr</groupId>
+		<groupId>solussd</groupId>
 		<artifactId>antlr4-master</artifactId>
 		<version>4.7.2-SNAPSHOT</version>
 	</parent>
@@ -29,7 +29,7 @@
 		<dependency>
 			<groupId>org.antlr</groupId>
 			<artifactId>ST4</artifactId>
-			<version>4.0.8</version>
+			<version>4.0.9-SNAPSHOT</version>
 		</dependency>
 		<dependency>
 			<groupId>org.abego.treelayout</groupId>

tool/src/org/antlr/v4/Tool.java

@@ -838,7 +838,7 @@ public class Tool {
 		// or just or the relative path recorded for the parent grammar. This means
 		// that when we write the tokens files, or the .java files for imported grammars
 		// taht we will write them in the correct place.
-		if (fileNameWithPath.lastIndexOf(File.separatorChar) == -1) {
+		if ((fileNameWithPath == null) || (fileNameWithPath.lastIndexOf(File.separatorChar) == -1)) {
 			// No path is included in the file name, so make the file
 			// directory the same as the parent grammar (which might sitll be just ""
 			// but when it is not, we will write the file in the correct place.

tool/src/org/antlr/v4/codegen/Target.java

@@ -26,6 +26,8 @@ import org.stringtemplate.v4.STGroupFile;
 import org.stringtemplate.v4.StringRenderer;
 import org.stringtemplate.v4.misc.STMessage;
 
+import java.net.URL;
+
 /** */
 public abstract class Target {
 	/** For pure strings of Java 16-bit Unicode char, how can we display
@@ -504,9 +506,10 @@ public abstract class Target {
 
 	public boolean templatesExist() {
 		String groupFileName = CodeGenerator.TEMPLATE_ROOT + "/" + getLanguage() + "/" + getLanguage() + STGroup.GROUP_FILE_EXTENSION;
+		URL url = Thread.currentThread().getContextClassLoader().getResource(groupFileName);
 		STGroup result = null;
 		try {
-			result = new STGroupFile(groupFileName);
+			result = new STGroupFile(url.getPath());
 		}
 		catch (IllegalArgumentException iae) {
 			result = null;
@@ -517,9 +520,11 @@ public abstract class Target {
 
 	protected STGroup loadTemplates() {
 		String groupFileName = CodeGenerator.TEMPLATE_ROOT + "/" + getLanguage() + "/" + getLanguage() + STGroup.GROUP_FILE_EXTENSION;
+		URL url = Thread.currentThread().getContextClassLoader().getResource(groupFileName);
+
 		STGroup result = null;
 		try {
-			result = new STGroupFile(groupFileName);
+			result = new STGroupFile(url.getPath());
 		}
 		catch (IllegalArgumentException iae) {
 			gen.tool.errMgr.toolError(ErrorType.MISSING_CODE_GEN_TEMPLATES,

tool/src/org/antlr/v4/tool/ErrorManager.java

@@ -231,8 +231,7 @@ public class ErrorManager {
             setFormat("antlr"); // recurse on this rule, trying the default message format
             return;
         }
-
-        format = new STGroupFile(fileName, "UTF-8");
+        format = new STGroupFile(url, "UTF-8", '<', '>');
         format.load();
 
         if ( !initSTListener.errors.isEmpty() ) {