Add tests for a few fixed issues

src/libsyntax/ext/base.rs

@@ -557,7 +557,7 @@ impl<'a> ExtCtxt<'a> {
         self.recursion_count += 1;
         if self.recursion_count > self.ecfg.recursion_limit {
             self.span_fatal(ei.call_site,
-                            format!("Recursion limit reached while expanding the macro `{}`",
+                            format!("recursion limit reached while expanding the macro `{}`",
                                     ei.callee.name).as_slice());
         }