Initial commit

yamllint/__init__.py

@@ -0,0 +1,80 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from yamllint import config
+from yamllint import parser
+
+
+APP_NAME = 'yamllint'
+APP_VERSION = '0.1.0'
+APP_DESCRIPTION = 'Lint YAML files.'
+
+__author__ = 'Adrien Vergé'
+__copyright__ = 'Copyright 2016, Adrien Vergé'
+__license__ = 'GPLv3'
+__version__ = APP_VERSION
+
+
+def _lint(buffer, conf):
+    rules = config.get_enabled_rules(conf)
+
+    # Split token rules from line rules
+    token_rules = [r for r in rules if r.TYPE == 'token']
+    line_rules = [r for r in rules if r.TYPE == 'line']
+
+    # If the document contains a syntax error, save it and yield it at the
+    # right line
+    syntax_error = parser.get_syntax_error(buffer)
+
+    for elem in parser.token_or_line_generator(buffer):
+        if syntax_error and syntax_error.line <= elem.line_no:
+            syntax_error.level = 'error'
+            yield syntax_error
+            syntax_error = None
+
+        if isinstance(elem, parser.Token):
+            for rule in token_rules:
+                rule_conf = conf[rule.ID]
+                for problem in rule.check(rule_conf,
+                                          elem.curr, elem.prev, elem.next):
+                    problem.rule = rule.ID
+                    problem.level = rule_conf['level']
+                    yield problem
+        elif isinstance(elem, parser.Line):
+            for rule in line_rules:
+                rule_conf = conf[rule.ID]
+                for problem in rule.check(rule_conf, elem):
+                    problem.rule = rule.ID
+                    problem.level = rule_conf['level']
+                    yield problem
+
+
+def lint(input, conf):
+    """Lints a YAML source.
+
+    Returns a generator of LintProblem objects.
+
+    :param input: buffer, string or stream to read from
+    :param conf: yamllint configuration object
+    """
+    if type(input) == str:
+        return _lint(input, conf)
+    elif hasattr(input, 'read'):  # Python 2's file or Python 3's io.IOBase
+        # We need to have everything in memory to parse correctly
+        content = input.read()
+        return _lint(content, conf)
+    else:
+        raise TypeError('input should be a string or a stream')

yamllint/conf/default.yml

@@ -0,0 +1,39 @@
+---
+
+rules:
+  #block-sequence-indentation:
+  #  present: yes
+  colons:
+    max-spaces-before: 0
+    max-spaces-after: 1
+  #comma:
+  #  max-spaces-before: 0
+  #  max-spaces-after: 1
+  #comment:
+  #  min-spaces-after: 1
+  #  min-spaces-before: 2
+  document-end: disable
+  document-start:
+    level: warning
+    present: yes
+  empty-lines:
+    max: 2
+    max-start: 0
+    max-end: 0
+  hyphens:
+    max-spaces-after: 1
+  indentation:
+    spaces: 2
+    #comments: yes
+  line-length:
+    max: 80
+  new-line-at-end-of-file: {level: error}
+  new-lines:
+    type: unix
+  #spaces-in-brackets:  [ 1, 2 ]
+  #  min: 1
+  #  max: 1
+  #spaces-in-braces:  { df: d }
+  #  min: 1
+  #  max: 1
+  trailing-spaces: {}

yamllint/config.py

@@ -0,0 +1,103 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import os.path
+
+import yaml
+
+import yamllint.rules
+from yamllint.errors import YamlLintConfigError
+
+
+def get_extended_conf(name):
+    # Is it a standard conf shipped with yamllint...
+    if '/' not in name:
+        std_conf = os.path.join(os.path.dirname(os.path.realpath(__file__)),
+                                'conf', name + '.yml')
+
+        if os.path.isfile(std_conf):
+            return std_conf
+
+    # or a custom conf on filesystem?
+    return name
+
+
+def extend_config(content):
+    try:
+        conf = yaml.safe_load(content)
+
+        if 'rules' not in conf:
+            conf['rules'] = {}
+
+        # Does this conf override another conf that we need to load?
+        if 'extends' in conf:
+            base = parse_config_from_file(get_extended_conf(conf['extends']))
+
+            base.update(conf['rules'])
+            conf['rules'] = base
+
+        return conf
+    except Exception as e:
+        raise YamlLintConfigError('invalid config: %s' % e)
+
+
+def parse_config(content):
+    conf = extend_config(content)
+    rules = {}
+
+    for id in conf['rules']:
+        try:
+            rule = yamllint.rules.get(id)
+        except Exception as e:
+            raise YamlLintConfigError('invalid config: %s' % e)
+
+        if conf['rules'][id] == 'disable':
+            continue
+
+        rules[id] = {'level': 'error'}
+        if type(conf['rules'][id]) == dict:
+            if 'level' in conf['rules'][id]:
+                if conf['rules'][id]['level'] not in ('error', 'warning'):
+                    raise YamlLintConfigError(
+                        'invalid config: level should be "error" or "warning"')
+                rules[id]['level'] = conf['rules'][id]['level']
+
+            options = getattr(rule, 'CONF', {})
+            for optkey in conf['rules'][id]:
+                if optkey == 'level':
+                    continue
+                if optkey not in options:
+                    raise YamlLintConfigError(
+                        'invalid config: unknown option "%s" for rule "%s"' %
+                        (optkey, id))
+                if type(conf['rules'][id][optkey]) != options[optkey]:
+                    raise YamlLintConfigError(
+                        'invalid config: option "%s" of "%s" should be %s' %
+                        (optkey, id, options[optkey].__name__))
+                rules[id][optkey] = conf['rules'][id][optkey]
+        else:
+            raise YamlLintConfigError(('invalid config: rule "%s": should be '
+                                       'either "disable" or a dict') % id)
+    return rules
+
+
+def parse_config_from_file(path):
+    with open(path) as f:
+        return parse_config(f.read())
+
+
+def get_enabled_rules(conf):
+    return [yamllint.rules.get(r) for r in conf.keys() if conf[r] is not False]

yamllint/errors.py

@@ -0,0 +1,50 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+class LintProblem(object):
+    def __init__(self, line, column, desc='<no description>', rule=None):
+        self.line = line
+        self.column = column
+        self.desc = desc
+        self.rule = rule
+        self.level = None
+
+    @property
+    def message(self):
+        if self.rule is not None:
+            return '%s (%s)' % (self.desc, self.rule)
+        return self.desc
+
+    def __eq__(self, other):
+        return (self.line == other.line and
+                self.column == other.column and
+                self.rule == other.rule)
+
+    def __lt__(self, other):
+        return (self.line < other.line or
+                (self.line == other.line and self.column < other.column))
+
+    def __repr__(self):
+        return '%d:%d: %s' % (self.line, self.column, self.message)
+
+
+class YamlLintError(Exception):
+    pass
+
+
+class YamlLintConfigError(YamlLintError):
+    pass

yamllint/output.py

@@ -0,0 +1,38 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+def parsable_format(problem, filename):
+    return ('%(file)s:%(line)s:%(column)s: [%(level)s] %(message)s' %
+            {'file': filename,
+             'line': problem.line,
+             'column': problem.column,
+             'level': problem.level,
+             'message': problem.message})
+
+
+def standard_format(problem, filename):
+    line = '  \033[2m%d:%d\033[0m' % (problem.line, problem.column)
+    line += max(20 - len(line), 0) * ' '
+    if problem.level == 'warning':
+        line += '\033[33m%s\033[0m' % problem.level
+    else:
+        line += '\033[31m%s\033[0m' % problem.level
+    line += max(38 - len(line), 0) * ' '
+    line += problem.desc
+    if problem.rule:
+        line += '  \033[2m(%s)\033[0m' % problem.rule
+    return line

yamllint/parser.py

@@ -0,0 +1,95 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import yaml
+
+from yamllint.errors import LintProblem
+
+
+class Line(object):
+    def __init__(self, line_no, buffer, start, end):
+        self.line_no = line_no
+        self.start = start
+        self.end = end
+        self.buffer = buffer
+
+    @property
+    def content(self):
+        return self.buffer[self.start:self.end]
+
+
+class Token(object):
+    def __init__(self, line_no, curr, prev, next):
+        self.line_no = line_no
+        self.curr = curr
+        self.prev = prev
+        self.next = next
+
+
+def line_generator(buffer):
+    line_no = 1
+    cur = 0
+    next = buffer.find('\n')
+    while next != -1:
+        yield Line(line_no, buffer, start=cur, end=next)
+        cur = next + 1
+        next = buffer.find('\n', cur)
+        line_no += 1
+
+    yield Line(line_no, buffer, start=cur, end=len(buffer))
+
+
+def token_generator(buffer):
+    yaml_loader = yaml.BaseLoader(buffer)
+
+    try:
+        prev = None
+        next = yaml_loader.peek_token()
+        while next is not None:
+            curr = yaml_loader.get_token()
+            next = yaml_loader.peek_token()
+
+            yield Token(curr.start_mark.line + 1, curr, prev, next)
+
+            prev = curr
+    except yaml.scanner.ScannerError:
+        pass
+
+
+def token_or_line_generator(buffer):
+    """Generator that mixes tokens and lines, ordering them by line number"""
+    token_gen = token_generator(buffer)
+    line_gen = line_generator(buffer)
+
+    token = next(token_gen, None)
+    line = next(line_gen, None)
+
+    while token is not None or line is not None:
+        if token is None or (line is not None and
+                             token.line_no > line.line_no):
+            yield line
+            line = next(line_gen, None)
+        else:
+            yield token
+            token = next(token_gen, None)
+
+
+def get_syntax_error(buffer):
+    try:
+        yaml.safe_load_all(buffer)
+    except yaml.error.MarkedYAMLError as e:
+        return LintProblem(e.problem_mark.line + 1, e.problem_mark.column + 1,
+                           'syntax error: ' + e.problem)

yamllint/rules/__init__.py

@@ -0,0 +1,48 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from yamllint.rules import (
+    colons,
+    document_end,
+    document_start,
+    empty_lines,
+    hyphens,
+    indentation,
+    line_length,
+    new_line_at_end_of_file,
+    new_lines,
+    trailing_spaces,
+)
+
+_RULES = {
+    colons.ID: colons,
+    document_end.ID: document_end,
+    document_start.ID: document_start,
+    empty_lines.ID: empty_lines,
+    hyphens.ID: hyphens,
+    indentation.ID: indentation,
+    line_length.ID: line_length,
+    new_line_at_end_of_file.ID: new_line_at_end_of_file,
+    new_lines.ID: new_lines,
+    trailing_spaces.ID: trailing_spaces,
+}
+
+
+def get(id):
+    if id not in _RULES:
+        raise ValueError('no such rule: "%s"' % id)
+
+    return _RULES[id]

yamllint/rules/colons.py

@@ -0,0 +1,46 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import yaml
+
+from yamllint.errors import LintProblem
+
+
+ID = 'colons'
+TYPE = 'token'
+CONF = {'max-spaces-before': int,
+        'max-spaces-after': int}
+
+
+def check(conf, token, prev, next):
+    if isinstance(token, yaml.ValueToken):
+        if (prev is not None and
+                prev.end_mark.line == token.start_mark.line and
+                conf['max-spaces-before'] != - 1 and
+                (prev.end_mark.pointer + conf['max-spaces-before'] <
+                 token.start_mark.pointer)):
+            yield LintProblem(token.start_mark.line + 1,
+                              token.start_mark.column,
+                              'too many spaces before colon')
+
+        if (next is not None and
+                token.end_mark.line == next.start_mark.line and
+                conf['max-spaces-after'] != - 1 and
+                (next.start_mark.pointer - token.end_mark.pointer >
+                 conf['max-spaces-after'])):
+            yield LintProblem(token.start_mark.line + 1,
+                              next.start_mark.column,
+                              'too many spaces after colon')

yamllint/rules/document_end.py

@@ -0,0 +1,44 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import yaml
+
+from yamllint.errors import LintProblem
+
+
+ID = 'document-end'
+TYPE = 'token'
+CONF = {'present': bool}
+
+
+def check(conf, token, prev, next):
+    if conf['present']:
+        if (isinstance(token, yaml.StreamEndToken) and
+                not (isinstance(prev, yaml.DocumentEndToken) or
+                     isinstance(prev, yaml.StreamStartToken))):
+            yield LintProblem(token.start_mark.line, 1,
+                              'missing document end "..."')
+        elif (isinstance(token, yaml.DocumentStartToken) and
+                not (isinstance(prev, yaml.DocumentEndToken) or
+                     isinstance(prev, yaml.StreamStartToken))):
+            yield LintProblem(token.start_mark.line + 1, 1,
+                              'missing document end "..."')
+
+    else:
+        if isinstance(token, yaml.DocumentEndToken):
+            yield LintProblem(token.start_mark.line + 1,
+                              token.start_mark.column + 1,
+                              'found forbidden document end "..."')

yamllint/rules/document_start.py

@@ -0,0 +1,43 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import yaml
+
+from yamllint.errors import LintProblem
+
+
+ID = 'document-start'
+TYPE = 'token'
+CONF = {'present': bool}
+
+
+# TODO: Don't fail if document contains directives such as
+# %YAML 1.2
+
+def check(conf, token, prev, next):
+    if conf['present']:
+        if ((isinstance(prev, yaml.StreamStartToken) or
+             isinstance(prev, yaml.DocumentEndToken)) and
+            not (isinstance(token, yaml.DocumentStartToken) or
+                 isinstance(token, yaml.StreamEndToken))):
+            yield LintProblem(token.start_mark.line + 1, 1,
+                              'missing document start "---"')
+
+    else:
+        if isinstance(token, yaml.DocumentStartToken):
+            yield LintProblem(token.start_mark.line + 1,
+                              token.start_mark.column + 1,
+                              'found forbidden document start "---"')

yamllint/rules/empty_lines.py

@@ -0,0 +1,59 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from yamllint.errors import LintProblem
+
+
+ID = 'empty-lines'
+TYPE = 'line'
+CONF = {'max': int,
+        'max-start': int,
+        'max-end': int}
+
+
+def check(conf, line):
+    if line.start == line.end and line.end < len(line.buffer):
+        # Only alert on the last blank line of a serie
+        if (line.end < len(line.buffer) - 1 and
+                line.buffer[line.end + 1] == '\n'):
+            return
+
+        blank_lines = 0
+
+        while (line.start > blank_lines and
+               line.buffer[line.start - blank_lines - 1] == '\n'):
+            blank_lines += 1
+
+        max = conf['max']
+
+        # Special case: start of document
+        if line.start - blank_lines == 0:
+            blank_lines += 1  # first line doesn't have a preceding \n
+            max = conf['max-start']
+
+        # Special case: end of document
+        # NOTE: The last line of a file is always supposed to end with a new
+        # line. See POSIX definition of a line at:
+        if line.end == len(line.buffer) - 1 and line.buffer[line.end] == '\n':
+            # Allow the exception of the one-byte file containing '\n'
+            if line.end == 0:
+                return
+
+            max = conf['max-end']
+
+        if blank_lines > max:
+            yield LintProblem(line.line_no, 1, 'too many blank lines (%d > %d)'
+                                               % (blank_lines, max))

yamllint/rules/hyphens.py

@@ -0,0 +1,34 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import yaml
+
+from yamllint.errors import LintProblem
+
+
+ID = 'hyphens'
+TYPE = 'token'
+CONF = {'max-spaces-after': int}
+
+
+def check(conf, token, prev, next):
+    if isinstance(token, yaml.BlockEntryToken):
+        if token.end_mark.line == next.start_mark.line:
+            if (next.start_mark.pointer - token.end_mark.pointer >
+                    conf['max-spaces-after']):
+                yield LintProblem(token.start_mark.line + 1,
+                                  next.start_mark.column,
+                                  'too many spaces after hyphen')

yamllint/rules/indentation.py

@@ -0,0 +1,63 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import yaml
+
+from yamllint.errors import LintProblem
+
+
+ID = 'indentation'
+TYPE = 'token'
+CONF = {'spaces': int}
+
+
+def check(conf, token, prev, next):
+    if isinstance(token, yaml.StreamEndToken):
+        return
+
+    if (prev is None or isinstance(prev, yaml.StreamStartToken) or
+            isinstance(prev, yaml.DirectiveToken) or
+            isinstance(prev, yaml.DocumentStartToken)):
+        if token.start_mark.column != 0:
+            yield LintProblem(
+                token.end_mark.line + 1, token.start_mark.column + 1,
+                'found indentation of %d instead of %d' %
+                (token.start_mark.column, 0))
+        return
+
+    if token.start_mark.line > prev.end_mark.line:
+        buffer = prev.end_mark.buffer
+
+        start = buffer.rfind('\n', 0, prev.end_mark.pointer) + 1
+        prev_indent = 0
+
+        # YAML recognizes two white space characters: space and tab.
+        # http://yaml.org/spec/1.2/spec.html#id2775170
+        while buffer[start + prev_indent] in ' \t':
+            prev_indent += 1
+
+        # Discard any leading '- '
+        if (buffer[start + prev_indent:start + prev_indent + 2] == '- '):
+            prev_indent += 2
+            while buffer[start + prev_indent] in ' \t':
+                prev_indent += 1
+
+        if (token.start_mark.column > prev_indent and
+                token.start_mark.column != prev_indent + conf['spaces']):
+            yield LintProblem(
+                token.end_mark.line + 1, token.start_mark.column + 1,
+                'found indentation of %d instead of %d' %
+                (token.start_mark.column, prev_indent + conf['spaces']))

yamllint/rules/line_length.py

@@ -0,0 +1,29 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from yamllint.errors import LintProblem
+
+
+ID = 'line-length'
+TYPE = 'line'
+CONF = {'max': int}
+
+
+def check(conf, line):
+    if line.end - line.start > conf['max']:
+        yield LintProblem(line.line_no, conf['max'] + 1,
+                          'line too long (%d > %d characters)' %
+                          (line.end - line.start, conf['max']))

yamllint/rules/new_line_at_end_of_file.py

@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from yamllint.errors import LintProblem
+
+
+ID = 'new-line-at-end-of-file'
+TYPE = 'line'
+
+
+def check(conf, line):
+    if line.end == len(line.buffer) and line.end > line.start:
+        yield LintProblem(line.line_no, line.end - line.start + 1,
+                          'no new line character at the end of file')

yamllint/rules/new_lines.py

@@ -0,0 +1,34 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from yamllint.errors import LintProblem
+
+
+ID = 'new-lines'
+TYPE = 'line'
+CONF = {'type': str}
+
+
+def check(conf, line):
+    if line.start == 0 and len(line.buffer) > line.end:
+        if conf['type'] == 'dos':
+            if line.buffer[line.end - 1:line.end + 1] != '\r\n':
+                yield LintProblem(1, line.end - line.start + 1,
+                                  'wrong new line character: expected \\r\\n')
+        else:
+            if line.end > 0 and line.buffer[line.end - 1] == '\r':
+                yield LintProblem(1, line.end - line.start,
+                                  'wrong new line character: expected \\n')

yamllint/rules/trailing_spaces.py

@@ -0,0 +1,39 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import string
+
+from yamllint.errors import LintProblem
+
+
+ID = 'trailing-spaces'
+TYPE = 'line'
+
+
+def check(conf, line):
+    if line.end == 0:
+        return
+
+    # YAML recognizes two white space characters: space and tab.
+    # http://yaml.org/spec/1.2/spec.html#id2775170
+
+    pos = line.end
+    while line.buffer[pos - 1] in string.whitespace and pos > line.start:
+        pos -= 1
+
+    if pos != line.end and line.buffer[pos] in ' \t':
+        yield LintProblem(line.line_no, pos - line.start + 1,
+                          'trailing spaces')