tweaked error message when wrapping an external exception

lib/Twig/Error.php

@@ -115,6 +115,12 @@ class Twig_Error extends Exception
     {
         $this->message = $this->rawMessage;
 
+        $dot = false;
+        if ('.' === substr($this->message, -1)) {
+            $this->message = substr($this->message, 0, -1);
+            $dot = true;
+        }
+
         if (null !== $this->filename) {
             $this->message .= sprintf(' in %s', json_encode($this->filename));
         }
@@ -122,6 +128,10 @@ class Twig_Error extends Exception
         if ($this->lineno >= 0) {
             $this->message .= sprintf(' at line %d', $this->lineno);
         }
+
+        if ($dot) {
+            $this->message .= '.';
+        }
     }
 
     protected function findTemplateInfo(Exception $e)

lib/Twig/Template.php

@@ -169,7 +169,7 @@ abstract class Twig_Template implements Twig_TemplateInterface
         } catch (Twig_Error $e) {
             throw $e;
         } catch (Exception $e) {
-            throw new Twig_Error_Runtime($e->getMessage(), -1, null, $e);
+            throw new Twig_Error_Runtime(sprintf('An exception has been thrown during the rendering of a template ("%s").', $e->getMessage()), -1, null, $e);
         }
     }
 

test/Twig/Tests/ErrorTest.php

@@ -43,7 +43,7 @@ class Twig_Tests_ErrorTest extends Twig_Tests_TestCase
 
             $this->fail();
         } catch (Twig_Error_Runtime $e) {
-            $this->assertEquals('Runtime error... in "index" at line 4', $e->getMessage());
+            $this->assertEquals('An exception has been thrown during the rendering of a template ("Runtime error...") in "index" at line 4.', $e->getMessage());
             $this->assertEquals(4, $e->getTemplateLine());
             $this->assertEquals('index', $e->getTemplateFile());
         }