bears/go: Add GoMetaLinterBear

Add GometalinterBear which replaces some of existing bears
like errcheck, vet etc

Closes #972

.ci/deps.sh

@@ -19,6 +19,7 @@ go get -u sourcegraph.com/sqs/goreturns
 go get -u golang.org/x/tools/cmd/gotype
 go get -u github.com/kisielk/errcheck
 go get -u github.com/BurntSushi/toml/cmd/tomlv
+go get -u gopkg.in/alecthomas/gometalinter.v1
 
 # Ruby commands
 bundle install --path=vendor/bundle --binstubs=vendor/bin --jobs=8 --retry=3

bears/go/GoMetaLinterBear.py

@@ -0,0 +1,45 @@
+from coalib.bearlib.abstractions.Linter import linter
+from dependency_management.requirements.GoRequirement import GoRequirement
+
+
+@linter(executable='gometalinter.v1',
+        use_stdout=True,
+        output_format='regex',
+        output_regex=r'(.*):(?P<line>\d*):(?P<column>\d*):'
+                      '(?P<message>.*) \((?:\w*)\)')
+class GoMetaLinterBear:
+    """
+    Checks the ``go`` code using ``gometalinter``. This will run
+    some set of golang linters over each file separately.
+    """
+    LANGUAGES = {'Go'}
+    REQUIREMENTS = {GoRequirement(
+        package='gopkg.in/alecthomas/gometalinter.v1', flag='-u')}
+    AUTHORS = {'The coala developers'}
+    AUTHORS_EMAILS = {'[email protected]'}
+    LICENSE = 'AGPL-3.0'
+    CAN_DETECT = {'Formatting', 'Syntax', 'Missing import',
+                  'Unused Code', 'Smell', 'Unreachable Code', 'Security'}
+    SEE_MORE = 'https://github.com/alecthomas/gometalinter'
+
+    @staticmethod
+    def create_arguments(filename, file, config_file,
+                         gometalinter_disable: str='',
+                         gometalinter_enable: str='',
+                         gometalinter_config: str=''):
+        """
+        :param gometalinter_disable:
+            Disable a linter.
+        :param gometalinter_enable:
+            Enable a linter.
+        :param gometalinter_config:
+            Path to a custom configuration file.
+        """
+        args = ()
+        if gometalinter_disable:
+            args += ('--disable=' + gometalinter_disable,)
+        if gometalinter_enable:
+            args += ('--enable=' + gometalinter_enable,)
+        if gometalinter_config:
+            args += ('--config=' + gometalinter_config,)
+        return args

tests/go/GoMetaLinterBearTest.py

@@ -0,0 +1,40 @@
+from bears.go.GoMetaLinterBear import GoMetaLinterBear
+from coalib.testing.LocalBearTestHelper import verify_local_bear
+
+good_file_errcheck = """package main
+import "fmt"
+func main() {
+    fmt.Println("Hello, Arch!")
+}
+"""
+
+bad_file_errcheck = """package main
+import "os"
+func main() {
+f, _ := os.Open("foo")
+f.Write([]byte("Hello, world."))
+f.Close()
+}
+"""
+
+good_file_imports = """package main
+
+import "os"
+
+func main() {
+\tf, _ := os.Open("foo")
+}"""
+
+bad_file_imports = """package main
+
+
+func main() {
+\tf, _ := os.Open("foo")
+}"""
+
+
+GoMetaLinterBearTest = verify_local_bear(GoMetaLinterBear,
+                                         valid_files=(good_file_errcheck,
+                                                      bad_file_imports),
+                                         invalid_files=(bad_file_errcheck,
+                                                        good_file_imports))