diff --git a/.travis.yml b/.travis.yml
index 8bf44f7..5d756b9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,12 +4,14 @@ cache:
   - pip
 
 install:
-  - sudo apt-get install graphviz debhelper python-all python-setuptools python3-all python3-setuptools python3-pip lintian
+  - sudo apt-get install graphviz debhelper python-all python-setuptools python3-all python3-setuptools python3-pip lintian fakeroot
 
+  
 script:
   - export PATH=/usr/bin:${PATH}
   - sudo -H python3 -m pip install --upgrade pip
-  - sudo -H python3 -m pip install -rrequirements.dev.txt --upgrade
+  - sudo -H python3 -m pip install --ignore-installed six urllib3
+  - sudo -H python3 -m pip install --ignore-installed -rrequirements.dev.txt --upgrade
   - python3 ./devtools/statuses.py --commit=${TRAVIS_COMMIT} --build-id=${TRAVIS_BUILD_ID} --token=${token} --pull-id=${TRAVIS_PULL_REQUEST}
   - ./devtools/coverage.sh python3
   - dpkg-buildpackage -uc -us
diff --git a/coverxygen/__init__.py b/coverxygen/__init__.py
index b74b212..c3f00e2 100644
--- a/coverxygen/__init__.py
+++ b/coverxygen/__init__.py
@@ -10,7 +10,7 @@
 
 __author__       = "Xavier MARCELET <xavier@marcelet.com>"
 __copyright__    = "Copyright (C) 2016 Xavier MARCELET"
-__version__      = "1.3.0"
+__version__      = "1.3.1"
 __description__  = "Generate doxygen's documentation coverage report"
 __url__          = "https://github.com/psycofdj/coverxygen"
 __download_url__ = "https://github.com/psycofdj/coverxygen/tarball/%s" % __version__
@@ -86,6 +86,7 @@ def extract_name(p_node):
     elif l_id is not None :
       return l_id
     Coverxygen.error("unable to deduce name from node %s", ET.tostring(p_node))
+    return None
 
   @staticmethod
   def extract_documented(p_node):
@@ -93,7 +94,7 @@ def extract_documented(p_node):
       l_node = p_node.find("./%s" % c_key)
       if l_node is not None:
         l_content = "".join(l_node.itertext()).strip()
-        if len(l_content):
+        if l_content:
           return True
     return False
 
@@ -145,7 +146,7 @@ def process_symbol(self, p_node, p_filePath):
   @staticmethod
   def merge_symbols(p_results, p_symbols):
     for c_symbol in p_symbols:
-      if not len(c_symbol):
+      if not c_symbol:
         continue
       l_file = c_symbol["file"]
       if not l_file in p_results:
@@ -223,7 +224,7 @@ def output_print_lcov(p_stream, p_results):
       for c_item in c_data:
         l_value = 1
         if not c_item["documented"]:
-          l_value = -1
+          l_value = 0
         p_stream.write("DA:%d,%d\n" % (c_item["line"], l_value))
       p_stream.write("end_of_record\n")
 
diff --git a/debian/changelog b/debian/changelog
index d9eb395..bfb1df9 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,15 @@
+coverxygen (1.3.1ppa1~xenial) xenial; urgency=medium
+
+  * fix generated value when item is undocumented
+
+ -- Xavier MARCELET <xavier@marcelet.com>  Mon, 02 Jul 2018 13:26:17 +0200
+
+coverxygen (1.3.1ppa1~trusty) xenial; urgency=medium
+
+  * fix generated value when item is undocumented
+
+ -- Xavier MARCELET <xavier@marcelet.com>  Mon, 02 Jul 2018 13:26:17 +0200
+
 coverxygen (1.3.0ppa1~xenial) xenial; urgency=medium
 
   * strengthen and sanitize code
diff --git a/devtools/statuses.py b/devtools/statuses.py
index a725c7c..e30a9af 100755
--- a/devtools/statuses.py
+++ b/devtools/statuses.py
@@ -212,7 +212,7 @@ def run_pylint(self):
     print("Running pylint     ")
     print("-------------------")
 
-    l_proc = subprocess.Popen(["python3", "./devtools/xtdlint.py", "--rcfile", ".pylintrc", "-j", "4", "coverxygen" ], stdout=subprocess.PIPE)
+    l_proc = subprocess.Popen(["python3", "./devtools/xtdlint.py", "--rcfile", ".pylintrc", "-j", "4", "coverxygen", "-r", "yes", "-s", "yes" ], stdout=subprocess.PIPE)
     l_proc.wait()
     try:
       l_lines      = l_proc.stdout.read().decode("utf-8")
diff --git a/devtools/xtdlint.py b/devtools/xtdlint.py
index e3adef9..93291f1 100755
--- a/devtools/xtdlint.py
+++ b/devtools/xtdlint.py
@@ -7,6 +7,8 @@
 
 #------------------------------------------------------------------#
 
+
+
 import os
 import sys
 import pylint
@@ -75,6 +77,10 @@ def _getStats(self):
 
 
   def _display(self, layout):
+    """Don't do nothing."""
+
+  def display_messages(self, layout):
+    self.m_linter._report_evaluation()
     print(json.dumps({
       "report"   : {
         "cloc" : {
@@ -103,7 +109,7 @@ def _display(self, layout):
         "errors" : self._getStats()
       },
       "errors" : self.m_data
-    }))
+    }), file=self.out)
 
 
 class XtdLint(PyLinter):