1 files changed, 43 insertions, 0 deletions
diff --git a/yaksh/compare_stdio.py b/yaksh/compare_stdio.py
new file mode 100644
index 0000000..ba258c3
--- /dev/null
+++ b/yaksh/compare_stdio.py
@@ -0,0 +1,43 @@
+try:
+    from itertools import zip_longest
+except ImportError:
+    from itertools import izip_longest as zip_longest
+
+class CompareOutputs(object):
+	
+	def _incorrect_user_lines(self, exp_lines, user_lines):
+	    err_line_no = []
+	    for i, (expected_line, user_line) in enumerate(zip_longest(exp_lines, user_lines)):
+	        if not user_line or not expected_line:
+	            err_line_no.append(i)
+	        else:
+	            if user_line.strip() != expected_line.strip():
+	                err_line_no.append(i)
+	    return err_line_no
+	
+	def compare_outputs(self, expected_output, user_output,given_input=None):
+	    given_lines = user_output.splitlines()
+	    exp_lines = expected_output.splitlines()
+	    # if given_input:
+	    #     given_input =  given_input.splitlines()
+	    msg = {"given_input":given_input,
+	           "expected_output": exp_lines,
+	           "user_output":given_lines
+	            }
+	    ng = len(given_lines)
+	    ne = len(exp_lines)
+	    if ng != ne:
+	        err_line_no = self._incorrect_user_lines(exp_lines, given_lines)
+	        msg["error_no"] = err_line_no
+	        msg["error"] = "We had expected {0} number of lines. We got {1} number of lines.".format(ne, ng)
+	        return False, msg
+	    else:
+	        err_line_no = self._incorrect_user_lines(exp_lines, given_lines)
+	        if err_line_no:
+	            msg["error_no"] = err_line_no
+	            msg["error"] = "Line number(s) {0} did not match."\
+	                            .format(", ".join(map(str,[x+1 for x in err_line_no])))
+	            return False, msg
+	        else:
+	            msg["error"] = "Correct answer"
+	            return True, msg