refs skygragon#6: use default testase if not provided

Signed-off-by: Eric Wang <skygragon@gmail.com>

Author: skygragon

lib/commands/test.js

@@ -51,15 +51,17 @@ cmd.handler = function(argv) {
     testcase = h.readStdin();
   }
 
-  if (!testcase || testcase === '')
-    return console.log('ERROR: missing testcase?');
-
   var keyword = h.getFilename(argv.filename);
   core.getProblem(keyword, function(e, problem) {
     if (e) return console.log('ERROR:', e);
 
+    if (testcase !== undefined)
+      problem.testcase = testcase.replace(/\\n/g, '\n');
+
+    if (!problem.testcase)
+      return console.log('ERROR: missing testcase?');
+
     problem.file = argv.filename;
-    problem.testcase = testcase.replace(/\\n/g, '\n');
 
     console.log('\nInput data:');
     console.log(problem.testcase);