bears/yaml: Add TravisLintBear

Closes #294

Author: yash-nisar

Diff for: Gemfile

@@ -7,3 +7,4 @@ gem "reek"
 gem "rubocop", "0.47.1"
 gem "scss_lint", require: false
 gem "sqlint"
+gem "travis", "1.8.8"

Diff for: bears/yaml/TravisLintBear.py

@@ -0,0 +1,30 @@
+from coalib.bearlib.abstractions.Linter import linter
+
+from dependency_management.requirements.GemRequirement import GemRequirement
+
+
+@linter(executable='travis',
+        output_format='regex',
+        output_regex=r'\[x\]\s+(?P<message>.+)')
+class TravisLintBear:
+    """
+    A validator for your ``.travis.yml`` that attempts to reduce common build
+    errors such as:
+
+    - invalid YAML
+    - missing language key
+    - unsupported runtime versions of Ruby, PHP, OTP, etc.
+    - deprecated features or runtime aliases
+    """
+
+    LANGUAGES = {'YAML'}
+    REQUIREMENTS = {GemRequirement('travis', '1.8.8')}
+    AUTHORS = {'The coala developers'}
+    AUTHORS_EMAILS = {'coala-devel@googlegroups.com'}
+    LICENSE = 'AGPL-3.0'
+    CAN_DETECT = {'Formatting', 'Syntax'}
+    SEE_MORE = 'https://docs.travis-ci.com/user/travis-lint'
+
+    @staticmethod
+    def create_arguments(filename, file, config_file):
+        return 'lint', filename

Diff for: tests/yaml/TravisLintBearTest.py

@@ -0,0 +1,73 @@
+import os
+from queue import Queue
+
+from coalib.results.Result import Result
+from coalib.results.RESULT_SEVERITY import RESULT_SEVERITY
+from coalib.settings.Section import Section
+from coalib.testing.LocalBearTestHelper import LocalBearTestHelper
+from coalib.testing.BearTestHelper import generate_skip_decorator
+
+from bears.yaml.TravisLintBear import TravisLintBear
+
+
+def get_testfile_path(name):
+    return os.path.join(os.path.dirname(__file__),
+                        'travislint_test_files',
+                        name)
+
+
+def load_testfile(name):
+    return open(get_testfile_path(name)).readlines()
+
+
+@generate_skip_decorator(TravisLintBear)
+class TravisLintBearTest(LocalBearTestHelper):
+
+    def setUp(self):
+        self.uut = TravisLintBear(Section('name'), Queue())
+
+    def test_good_file(self):
+        file_name = '.good_travis.yml'
+        file_contents = load_testfile(file_name)
+        self.check_results(
+            self.uut,
+            file_contents,
+            [],
+            filename=get_testfile_path(file_name))
+
+    def test_bad_file(self):
+        file_name = '.bad_travis.yml'
+        file_contents = load_testfile(file_name)
+        self.check_results(
+            self.uut,
+            file_contents,
+            [Result.from_values('TravisLintBear',
+                                message='in matrix.exclude section: '
+                                        'specified ruby, but setting is '
+                                        'not relevant for python',
+                                file=get_testfile_path(file_name),
+                                severity=RESULT_SEVERITY.NORMAL),
+             Result.from_values('TravisLintBear',
+                                message='in os section: dropping osx, does'
+                                        ' not support python',
+                                file=get_testfile_path(file_name),
+                                severity=RESULT_SEVERITY.NORMAL),
+             Result.from_values('TravisLintBear',
+                                message='specified ruby, but setting is '
+                                        'not relevant for python',
+                                file=get_testfile_path(file_name),
+                                severity=RESULT_SEVERITY.NORMAL)],
+            filename=get_testfile_path(file_name))
+
+    def test_empty_file(self):
+        file_name = '.empty_travis.yml'
+        file_contents = load_testfile(file_name)
+        self.check_results(
+            self.uut,
+            file_contents,
+            [Result.from_values('TravisLintBear',
+                                message='missing key language, defaulting '
+                                        'to ruby',
+                                file=get_testfile_path(file_name),
+                                severity=RESULT_SEVERITY.NORMAL)],
+            filename=get_testfile_path(file_name))

Diff for: tests/yaml/travislint_test_files/.bad_travis.yml

@@ -0,0 +1,28 @@
+language: python
+sudo: false
+cache: bundler
+rvm:
+  - 1.9.2
+  - 1.9.3
+  - 2.0.0
+  - 2.1.0
+  - 2.1.3
+  - jruby
+os:
+  - linux
+  - osx
+matrix:
+  exclude:
+    - rvm: 1.8.7
+      os: osx
+    - rvm: 1.9.2
+      os: osx
+    - rvm: 2.1.0
+      os: osx
+    - rvm: jruby
+      os: osx
+deploy:
+  provider: rubygems
+  api_key:
+    secure: abcdef
+  gem: travis

Diff for: tests/yaml/travislint_test_files/.empty_travis.yml

@@ -0,0 +1,28 @@
+language: ruby
+sudo: false
+cache: bundler
+rvm:
+  - 1.9.2
+  - 1.9.3
+  - 2.0.0
+  - 2.1.0
+  - 2.1.3
+  - jruby
+os:
+  - linux
+  - osx
+matrix:
+  exclude:
+    - rvm: 1.8.7
+      os: osx
+    - rvm: 1.9.2
+      os: osx
+    - rvm: 2.1.0
+      os: osx
+    - rvm: jruby
+      os: osx
+deploy:
+  provider: rubygems
+  api_key:
+    secure: abcdef
+  gem: travis