add information when a property is missing with file and line number

webserver/http-templating-dev/src/main/java/org/webpieces/templating/impl/source/ScriptWriter.java

@@ -99,12 +99,14 @@ public void printScript() {
 
 	public void printExpression(TokenImpl token, ScriptOutputImpl sourceCode) {
 		String expr = token.getValue().trim();
+		sourceCode.println(         "enterExpression('"+token.getSourceLocation(false)+"');"); //purely so we can add info to missing properties
 		if(expr.startsWith("_"))
 			sourceCode.print("      __out.print("+expr+");");
 		else
 			sourceCode.print("      __out.print(useFormatter("+expr+"));");
         sourceCode.appendTokenComment(token);
         sourceCode.println();
+		sourceCode.println(         "exitExpression();");
 	}
 
 	public void printMessage() {

webserver/http-templating-dev/src/main/java/org/webpieces/templating/impl/source/TokenImpl.java

@@ -1,6 +1,7 @@
 package org.webpieces.templating.impl.source;
 
 import org.webpieces.templating.api.Token;
+import org.webpieces.templating.impl.GroovyTemplateSuperclass;
 
 public class TokenImpl implements Token {
 
@@ -51,7 +52,7 @@ public String getSourceLocation(boolean dueToError) {
 		if(!dueToError)
 			return loc;
 
-		return "\n\t"+loc+"\n";
+		return GroovyTemplateSuperclass.modifySourceLocation2(loc);
 	}
 
 	@Override

webserver/http-templating/src/main/java/org/webpieces/templating/impl/GroovyTemplateSuperclass.java

@@ -25,6 +25,7 @@ public abstract class GroovyTemplateSuperclass extends Script {
 	private Map<Object, Object> setTagProperties;
 	private String superTemplateFilePath;
 	private ReverseUrlLookup urlLookup;
+	private ThreadLocal<String> sourceLocal = new ThreadLocal<>();
 
     public void initialize(EscapeCharactersFormatter f, HtmlTagLookup tagLookup, 
     		Map<Object, Object> templateProps, ReverseUrlLookup urlLookup) {
@@ -47,13 +48,13 @@ public String useFormatter(Object val) {
     }
 
     protected void runTag(String tagName, Map<Object, Object> args, Closure<?> closure, String srcLocation) {
-    	srcLocation = "\n\t"+srcLocation+"\n";
+    	srcLocation = modifySourceLocation2(srcLocation);
     	HtmlTag tag = tagLookup.lookup(tagName);
     	PrintWriter writer = (PrintWriter) getProperty(OUT_PROPERTY_NAME);
     	try {
     		tag.runTag(args, closure, writer, this, srcLocation);
     	} catch(Exception e) {
-			throw new RuntimeException("Error running tag "+tagName+"("+e.getMessage()+").  "+srcLocation, e);
+			throw new RuntimeException("Error running tag #{"+tagName+"}#.  See exception cause below."+srcLocation, e);
     	}
     }
 
@@ -78,7 +79,7 @@ public Map<Object, Object> getSetTagProperties() {
 	}
 
 	public String fetchUrl(String routeId, Map<?, ?> args, String srcLocation) {
-		srcLocation = "\n\t"+srcLocation+"\n";
+    	srcLocation = modifySourceLocation2(srcLocation);
 		try {
 			Map<String, String> urlParams = new HashMap<>();
 			for(Map.Entry<?, ?> entry : args.entrySet()) {
@@ -98,13 +99,28 @@ public String fetchUrl(String routeId, Map<?, ?> args, String srcLocation) {
 
     @Override
     public Object getProperty(String property) {
+    	String srcLocation = sourceLocal.get();
+    	srcLocation = modifySourceLocation2(srcLocation);
         try {
             return super.getProperty(property);
         } catch (MissingPropertyException e) {
-        	throw new IllegalArgumentException("No such property '"+property+"' but perhaps you forgot quotes around it or you forgot to pass it in from the controller's return value(with the RouteId) OR lastly, if this is inside a custom tag, perhaps the tag did not pass in the correct arguments", e);
+        	throw new IllegalArgumentException("No such property '"+property+"' but perhaps you forgot quotes "
+        			+ "around it or you forgot to pass it in from the controller's return value(with the RouteId) OR "
+        			+ "lastly, if this is inside a custom tag, perhaps the tag did not pass in the correct arguments."+srcLocation, e);
         }
     }
 
+	public static String modifySourceLocation2(String srcLocation) {
+		return "\n\n\t"+srcLocation+"\n";
+	}
+
+    public void enterExpression(String srcLocation) {
+    	sourceLocal.set(srcLocation);
+    }
+
+    public void exitExpression() {
+    	sourceLocal.set(null);
+    }
 	public ReverseUrlLookup getUrlLookup() {
 		return urlLookup;
 	}