Make compiled templates more debuggable.

Former-commit-id: aba1aa3efcea6695632aae0eb61148aa3174debd

lodash.js

@@ -3421,7 +3421,11 @@
       text += '\n//@ sourceURL=/lodash/template/source[' + (templateCounter++) + ']';
     }
 
-    result = Function('_', 'return ' + text)(lodash);
+    try {
+      result = Function('_', 'return ' + text)(lodash);
+    } catch(e) {
+      result = function() { throw e; };
+    }
 
     if (data) {
       return result(data);

test/test.js

@@ -734,6 +734,15 @@
       deepEqual(options, {});
     });
 
+    test('should be debuggable if compiled with errors', function() {
+      var source = _.template('<% if x %>').source;
+      ok(source.indexOf('__p') > -1);
+    });
+
+    test('should raise an error if a template, compiled with errors, is executed', function() {
+      raises(_.template('<% if x %>'));
+    });
+
     test('should work with complex "interpolate" delimiters', function() {
       _.each({
         '<%= a + b %>': '3',