Kill AbstractClass in favor of abc.ABC{,Meta}.

contrib/go/src/python/pants/contrib/go/subsystems/BUILD

@@ -17,7 +17,6 @@ python_library(
     'src/python/pants/subsystem',
     'src/python/pants/util:contextutil',
     'src/python/pants/util:memo',
-    'src/python/pants/util:meta',
     'src/python/pants/util:process_handler',
   ],
 )

contrib/go/src/python/pants/contrib/go/subsystems/fetcher.py

@@ -5,11 +5,10 @@
 from __future__ import absolute_import, division, print_function, unicode_literals
 
 import logging
-from abc import abstractmethod
+from abc import ABC, abstractmethod
 from collections import namedtuple
 
 from pants.scm.git import Git
-from pants.util.meta import AbstractClass
 
 from pants.contrib.go.subsystems.fetch_error import FetchError
 from pants.contrib.go.targets.go_remote_library import GoRemoteLibrary
@@ -18,7 +17,7 @@
 logger = logging.getLogger(__name__)
 
 
-class Fetcher(AbstractClass):
+class Fetcher(ABC):
   """Knows how to interpret remote import paths and fetch code to satisfy them."""
 
   def __init__(self, import_path):

contrib/go/tests/python/pants_test/contrib/go/targets/BUILD

@@ -6,7 +6,6 @@ python_library(
   dependencies=[
     'contrib/go/src/python/pants/contrib/go:plugin',
     'src/python/pants/build_graph',
-    'src/python/pants/util:meta',
     'tests/python/pants_test:test_base',
   ]
 )

contrib/go/tests/python/pants_test/contrib/go/targets/go_local_source_test_base.py

@@ -4,17 +4,16 @@
 
 from __future__ import absolute_import, division, print_function, unicode_literals
 
-from abc import abstractproperty
+from abc import ABC, abstractproperty
 from textwrap import dedent
 
 from pants.build_graph.address_lookup_error import AddressLookupError
-from pants.util.meta import AbstractClass
 from pants_test.test_base import TestBase
 
 from pants.contrib.go.register import build_file_aliases
 
 
-class GoLocalSourceTestBase(AbstractClass):
+class GoLocalSourceTestBase(ABC):
   # NB: We assume we're mixed into a TestBase - we can't extend that directly or else unittest tries
   # to run our test methods in the subclass (OK), and against us (not OK).
   # NB: We use aliases and BUILD files to test proper registration of anonymous targets and macros.

contrib/node/src/python/pants/contrib/node/subsystems/BUILD

@@ -9,7 +9,6 @@ python_library(
     'src/python/pants/subsystem',
     'src/python/pants/util:contextutil',
     'src/python/pants/util:memo',
-    'src/python/pants/util:meta',
     'src/python/pants/util:process_handler',
   ],
 )

contrib/node/src/python/pants/contrib/node/subsystems/resolvers/BUILD

@@ -46,6 +46,5 @@ python_library(
   dependencies=[
     'src/python/pants/base:build_environment',
     'src/python/pants/util:dirutil',
-    'src/python/pants/util:meta',
   ]
 )

contrib/node/src/python/pants/contrib/node/subsystems/resolvers/node_resolver_base.py

@@ -7,14 +7,13 @@
 import os
 import re
 import shutil
-from abc import abstractmethod
+from abc import ABC, abstractmethod
 
 from pants.base.build_environment import get_buildroot
 from pants.util.dirutil import safe_mkdir
-from pants.util.meta import AbstractClass
 
 
-class NodeResolverBase(AbstractClass):
+class NodeResolverBase(ABC):
 
   file_regex = re.compile('^file:(.*)$')
 

contrib/node/src/python/pants/contrib/node/tasks/node_paths.py

@@ -4,13 +4,13 @@
 
 from __future__ import absolute_import, division, print_function, unicode_literals
 
-from pants.util.meta import AbstractClass
+from abc import ABC
 
 
 # TODO(John Sirois): UnionProducts? That seems broken though for ranged version constraints,
 # which npm has and are widely used in the community.  For now stay dumb simple (and slow) and
 # resolve each node_module individually.
-class NodePathsBase(AbstractClass):
+class NodePathsBase(ABC):
   """Maps NpmPackage targets to their resolved NODE_PATH."""
 
   def __init__(self):

src/python/pants/backend/jvm/targets/BUILD

@@ -44,7 +44,6 @@ python_library(
     'src/python/pants/fs',
     'src/python/pants/source',
     'src/python/pants/util:memo',
-    'src/python/pants/util:meta',
     'src/python/pants/util:netrc',
     'src/python/pants/util:objects',
   ],

src/python/pants/backend/jvm/targets/credentials.py

@@ -5,16 +5,15 @@
 from __future__ import absolute_import, division, print_function, unicode_literals
 
 import functools
-from abc import abstractmethod
+from abc import ABCMeta, abstractmethod
 
 from pants.base.exceptions import TargetDefinitionException
 from pants.build_graph.target import Target
 from pants.util.memo import memoized_method
-from pants.util.meta import AbstractClass
 from pants.util.netrc import Netrc
 
 
-class Credentials(Target, AbstractClass):
+class Credentials(Target, metaclass=ABCMeta):
   """Credentials for a maven repository.
 
   The ``publish.jar`` section of your ``pants.ini`` file can refer to one

src/python/pants/backend/jvm/targets/jarable.py

@@ -4,13 +4,12 @@
 
 from __future__ import absolute_import, division, print_function, unicode_literals
 
-from abc import abstractproperty
+from abc import ABC, abstractproperty
 
 from pants.java.jar.jar_dependency import JarDependency
-from pants.util.meta import AbstractClass
 
 
-class Jarable(AbstractClass):
+class Jarable(ABC):
   """A mixin that identifies a target as one that can provide a jar.
 
   :API: public

src/python/pants/backend/jvm/targets/jvm_binary.py

@@ -5,6 +5,7 @@
 from __future__ import absolute_import, division, print_function, unicode_literals
 
 import re
+from abc import ABCMeta
 from hashlib import sha1
 
 from future.utils import PY3, string_types
@@ -16,10 +17,9 @@
                                       PrimitiveField)
 from pants.base.validation import assert_list
 from pants.java.jar.exclude import Exclude
-from pants.util.meta import AbstractClass
 
 
-class JarRule(FingerprintedMixin, AbstractClass):
+class JarRule(FingerprintedMixin, metaclass=ABCMeta):
 
   def __init__(self, apply_pattern, payload=None):
     self.payload = payload or Payload()

src/python/pants/backend/jvm/tasks/BUILD

@@ -368,7 +368,6 @@ python_library(
     'src/python/pants/binaries',
     'src/python/pants/java/jar',
     'src/python/pants/util:contextutil',
-    'src/python/pants/util:meta',
   ],
 )
 
@@ -417,7 +416,6 @@ python_library(
     'src/python/pants/util:desktop',
     'src/python/pants/util:dirutil',
     'src/python/pants/util:memo',
-    'src/python/pants/util:meta',
     'src/python/pants/util:process_handler',
     'src/python/pants/util:strutil',
   ],
@@ -718,7 +716,6 @@ python_library(
     'src/python/pants/build_graph',
     'src/python/pants/option',
     'src/python/pants/util:dirutil',
-    'src/python/pants/util:meta',
     'src/python/pants/util:memo',
   ]
 )

src/python/pants/backend/jvm/tasks/coverage/engine.py

@@ -4,16 +4,15 @@
 
 from __future__ import absolute_import, division, print_function, unicode_literals
 
-from abc import abstractmethod
+from abc import ABC, abstractmethod
 
 from pants.backend.jvm.targets.annotation_processor import AnnotationProcessor
 from pants.backend.jvm.targets.java_library import JavaLibrary
 from pants.backend.jvm.targets.scala_library import ScalaLibrary
-from pants.util.meta import AbstractClass
 from pants.util.objects import datatype
 
 
-class CoverageEngine(AbstractClass):
+class CoverageEngine(ABC):
   """The interface JVM code coverage processors must support.
 
   This is a stateful interface that will be called via the following sequence:

src/python/pants/backend/jvm/tasks/jar_task.py

@@ -7,7 +7,7 @@
 import os
 import shutil
 import tempfile
-from abc import abstractmethod
+from abc import ABC, abstractmethod
 from builtins import bytes, object, open
 from contextlib import contextmanager
 
@@ -25,7 +25,6 @@
 from pants.java.util import relativize_classpath
 from pants.util.contextutil import temporary_dir
 from pants.util.dirutil import safe_mkdtemp
-from pants.util.meta import AbstractClass
 
 
 class Jar(object):
@@ -41,7 +40,7 @@ class Jar(object):
   class Error(Exception):
     """Indicates an error creating or updating a jar on disk."""
 
-  class Entry(AbstractClass):
+  class Entry(ABC):
     """An entry to be written to a jar."""
 
     def __init__(self, dest):
@@ -363,7 +362,7 @@ def open_jar(self, path, overwrite=False, compressed=True, jar_rules=None):
 
 class JarBuilderTask(JarTask):
 
-  class JarBuilder(AbstractClass):
+  class JarBuilder(ABC):
     """A utility to aid in adding the classes and resources associated with targets to a jar.
 
     :API: public

src/python/pants/backend/jvm/tasks/reports/junit_html_report.py

@@ -9,15 +9,14 @@
 import logging
 import os
 import xml.etree.ElementTree as ET
-from abc import abstractmethod
+from abc import ABC, abstractmethod
 from builtins import map, next, object, open
 from collections import defaultdict
 from functools import total_ordering
 
 from pants.base.mustache import MustacheRenderer
 from pants.util.dirutil import safe_mkdir_for, safe_walk
 from pants.util.memo import memoized_property
-from pants.util.meta import AbstractClass
 from pants.util.objects import datatype
 
 
@@ -173,7 +172,7 @@ def as_dict(self):
     return d
 
 
-class JUnitHtmlReportInterface(AbstractClass):
+class JUnitHtmlReportInterface(ABC):
   """The interface JUnit html reporters must support."""
 
   @abstractmethod

src/python/pants/backend/jvm/tasks/rewrite_base.py

@@ -6,7 +6,7 @@
 
 import os
 import shutil
-from abc import abstractmethod, abstractproperty
+from abc import ABCMeta, abstractmethod, abstractproperty
 
 from pants.backend.jvm.tasks.nailgun_task import NailgunTask
 from pants.base.build_environment import get_buildroot
@@ -15,10 +15,9 @@
 from pants.process.xargs import Xargs
 from pants.util.dirutil import fast_relpath, safe_mkdir_for_all
 from pants.util.memo import memoized_property
-from pants.util.meta import AbstractClass
 
 
-class RewriteBase(NailgunTask, AbstractClass):
+class RewriteBase(NailgunTask, metaclass=ABCMeta):
   """Abstract base class for JVM-based tools that check/rewrite sources."""
 
   @classmethod

src/python/pants/backend/native/config/BUILD

@@ -6,7 +6,6 @@ python_library(
   dependencies=[
     '3rdparty/python:future',
     'src/python/pants/engine:rules',
-    'src/python/pants/util:meta',
     'src/python/pants/util:objects',
     'src/python/pants/util:osutil',
   ],

src/python/pants/backend/native/config/environment.py

@@ -5,11 +5,10 @@
 from __future__ import absolute_import, division, print_function, unicode_literals
 
 import os
-from abc import abstractmethod, abstractproperty
+from abc import ABC, abstractmethod, abstractproperty
 
 from pants.engine.rules import rule
 from pants.util.memo import memoized_classproperty
-from pants.util.meta import AbstractClass
 from pants.util.objects import datatype, enum
 from pants.util.osutil import all_normalized_os_names, get_normalized_os_name
 from pants.util.strutil import create_path_env_var
@@ -45,7 +44,7 @@ def wrapper(cls):
 # NB: prototypal inheritance seems *deeply* linked with the idea here!
 # TODO: since we are calling these methods from other files, we should remove the leading underscore
 # and add testing!
-class _ExtensibleAlgebraic(AbstractClass):
+class _ExtensibleAlgebraic(ABC):
   """A mixin to make it more concise to coalesce datatypes with related collection fields."""
 
   @memoized_classproperty

src/python/pants/backend/native/targets/native_library.py

@@ -4,16 +4,17 @@
 
 from __future__ import absolute_import, division, print_function, unicode_literals
 
+from abc import ABCMeta
+
 from pants.backend.native.subsystems.native_build_step import ToolchainVariant
 from pants.backend.native.targets.native_artifact import NativeArtifact
 from pants.base.exceptions import TargetDefinitionException
 from pants.base.payload import Payload
 from pants.base.payload_field import PrimitiveField, PrimitivesSetField
 from pants.build_graph.target import Target
-from pants.util.meta import AbstractClass
 
 
-class NativeLibrary(Target, AbstractClass):
+class NativeLibrary(Target, metaclass=ABCMeta):
   """A class wrapping targets containing sources for C-family languages and related code."""
 
   # TODO: replace this awkward classmethod with a mixin!

src/python/pants/backend/native/tasks/native_compile.py

@@ -5,15 +5,15 @@
 from __future__ import absolute_import, division, print_function, unicode_literals
 
 import os
-from abc import abstractmethod
+from abc import ABCMeta, abstractmethod
 from collections import defaultdict
 
 from pants.backend.native.tasks.native_task import NativeTask
 from pants.base.build_environment import get_buildroot
 from pants.base.exceptions import TaskError
 from pants.base.workunit import WorkUnit, WorkUnitLabel
 from pants.util.memo import memoized_method, memoized_property
-from pants.util.meta import AbstractClass, classproperty
+from pants.util.meta import classproperty
 from pants.util.objects import datatype
 from pants.util.process_handler import subprocess
 
@@ -36,7 +36,7 @@ def file_paths(self):
     return [os.path.join(self.root_dir, fname) for fname in self.filenames]
 
 
-class NativeCompile(NativeTask, AbstractClass):
+class NativeCompile(NativeTask, metaclass=ABCMeta):
   # `NativeCompile` will use the `source_target_constraint` to determine what targets have "sources"
   # to compile, and the `dependent_target_constraint` to determine which dependent targets to
   # operate on for `strict_deps` calculation.

src/python/pants/backend/python/tasks/BUILD

@@ -32,7 +32,6 @@ python_library(
     'src/python/pants/util:dirutil',
     'src/python/pants/util:fileutil',
     'src/python/pants/util:memo',
-    'src/python/pants/util:meta',
     'src/python/pants/util:objects',
     'src/python/pants/util:process_handler',
     'src/python/pants/util:py2_compat',