Add a checker for the documentation

This patchset add some unit tests on the documentation:
Checking wrapping
Checking trailing spaces
Checking no_cr

Change-Id: I3fa56d3e7dd3218dcd398e6750bdd2fb3a8e75b4

watcher/tests/test_doc_formatting.py

@@ -0,0 +1,79 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+import os
+import re
+import testtools
+
+
+class TestDocFormatting(testtools.TestCase):
+    def _check_lines_wrapping(self, tpl, raw):
+        code_block = False
+        for i, line in enumerate(raw.split("\n"), start=1):
+            # NOTE(ndipanov): Allow code block lines to be longer than 79 ch
+            if code_block:
+                if not line or line.startswith(" "):
+                    continue
+                else:
+                    code_block = False
+            if "::" in line:
+                code_block = True
+            if "http://" in line or "https://" in line:
+                continue
+            # Allow lines which do not contain any whitespace
+            if re.match("\s*[^\s]+$", line):
+                continue
+            if code_block is False:
+                self.assertTrue(
+                    len(line) < 80,
+                    msg="%s:%d: Line limited to a maximum of 79 characters." %
+                        (tpl, i))
+
+    def _check_no_cr(self, tpl, raw):
+        cr = '\r'
+        matches = re.findall(cr, raw)
+        self.assertEqual(
+            len(matches), 0,
+            "Found %s literal carriage returns in file %s" %
+            (len(matches), tpl))
+
+    def _check_trailing_spaces(self, tpl, raw):
+        for i, line in enumerate(raw.split("\n"), start=1):
+            trailing_spaces = re.findall(" +$", line)
+            self.assertEqual(len(trailing_spaces), 0,
+                             "Found trailing spaces on line %s of %s" % (
+                                 i, tpl))
+
+    def _check_tab(self, tpl, raw):
+        tab = '\t'
+        matches = re.findall(tab, raw)
+        self.assertEqual(
+            len(matches), 0,
+            "Found %s tab in file %s" %
+            (len(matches), tpl))
+
+    def test_template(self):
+        doc_path = os.path.join("doc", 'source')
+        for root, dirs, files in os.walk(top=doc_path):
+            for file in files:
+                absolute_path_file = os.path.join(root, file)
+
+                if not os.path.isdir(absolute_path_file):
+                    if not absolute_path_file.endswith(".rst"):
+                        continue
+
+                    with open(absolute_path_file) as f:
+                        data = f.read()
+
+                    self._check_tab(absolute_path_file, data)
+                    self._check_lines_wrapping(absolute_path_file, data)
+                    self._check_no_cr(absolute_path_file, data)
+                    self._check_trailing_spaces(absolute_path_file, data)