PHPStanBear: Add PHPStanBear

Introduce PHPStanBear
Checks the code with ``phpstan analyze``.
Closes coala#1426

bears/php/PHPStanBear.py

@@ -0,0 +1,37 @@
+import os
+
+from coalib.bearlib.abstractions.Linter import linter
+
+
+@linter(executable='phpstan',
+        output_format='regex',
+        output_regex=r'(?P<line>\d+)  (?P<message>.*)')
+class PHPStanBear:
+    """
+    Checks the code with ``phpstan analyze``.
+    This can run it on multiple files and folders.
+    See <https://github.com/phpstan/phpstan> for more information.
+    """
+    LANGUAGES = {'PHP'}
+    AUTHORS = {'The coala developers'}
+    AUTHORS_EMAILS = {'[email protected]'}
+    LICENSE = 'AGPL-3.0'
+    CAN_DETECT = {'Syntax', 'Unused Code', 'Variable Misuse',
+                  'Undefined Element', 'Missing Import', 'Spelling'}
+
+    @staticmethod
+    def create_arguments(filename, file, config_file, phpstan_level: str='0', phpstan_config: str=''):
+        """
+        :param phpstan_config:
+            path to a custom configuration file.
+            When using a custom project config file, you have to pass the phpstan_level argument
+            (default value 0 does not apply here).
+        :param phpstan_level:
+            To set rule levels.
+            0 is the loosest and 4 is the strictest.
+            See <https://github.com/phpstan/phpstan> for more information.
+        """
+        args = ('analyse', '--level='+phpstan_level, filename)
+        if phpstan_config:
+            args += ('-c '+phpstan_config,)
+        return args

tests/php/PHPStanBearTest.py

@@ -0,0 +1,23 @@
+from bears.php.PHPStanBear import PHPStanBear
+from coalib.testing.LocalBearTestHelper import verify_local_bear
+
+
+good_file = """
+<?php
+    $a = 1;
+?>
+"""
+
+
+bad_file = """
+<?php
+    $a =
+?>
+"""
+
+
+PHPStanBearTest = verify_local_bear(
+    PHPStanBear,
+    valid_files=(good_file,),
+    invalid_files=(bad_file,),
+    tempfile_kwargs={'suffix': '.php'})