Move Black into a plugin to enable turning it on and off via backend_plugins

pants.ini

@@ -46,10 +46,6 @@ pythonpath: [
 
 backend_packages: +[
     "pants.backend.docgen",
-    "internal_backend.rules_for_testing",
-    "internal_backend.repositories",
-    "internal_backend.sitegen",
-    "internal_backend.utilities",
     "pants.contrib.avro",
     "pants.contrib.awslambda.python",
     "pants.contrib.buildrefactor",
@@ -66,6 +62,10 @@ backend_packages: +[
     "pants.contrib.python.checks",
     "pants.contrib.scrooge",
     "pants.contrib.thrifty",
+    "internal_backend.rules_for_testing",
+    "internal_backend.repositories",
+    "internal_backend.sitegen",
+    "internal_backend.utilities",
   ]
 
 # The pants script in this repo consumes these files to run pants
@@ -82,8 +82,6 @@ pants_ignore: +[
     '/build-support/bin/native/src',
   ]
 
-[black]
-config: pyproject.toml
 
 [cache]
 # Caching is on globally by default, but we disable it here for development purposes.

src/python/pants/backend/python/lint/black/BUILD

@@ -0,0 +1,46 @@
+# Copyright 2019 Pants project contributors (see CONTRIBUTORS.md).
+# Licensed under the Apache License, Version 2.0 (see LICENSE).
+
+python_library(
+  dependencies=[
+    '3rdparty/python:dataclasses',
+    'src/python/pants/backend/python/subsystems',
+    'src/python/pants/backend/python/rules',
+    'src/python/pants/backend/python/targets',
+    'src/python/pants/engine:fs',
+    'src/python/pants/engine:isolated_process',
+    'src/python/pants/engine:rules',
+    'src/python/pants/engine:selectors',
+    'src/python/pants/option',
+    'src/python/pants/rules/core',
+  ],
+)
+
+python_tests(
+  name='tests',
+  sources=globs('*_test.py', exclude=[globs('*_integration_test.py')]),
+  dependencies=[
+    ':black',
+  ],
+)
+
+
+python_tests(
+  name='integration',
+  sources=globs('*_integration_test.py'),
+  dependencies=[
+    ':black',
+    'src/python/pants/backend/python/subsystems',
+    'src/python/pants/backend/python/targets',
+    'src/python/pants/engine:fs',
+    'src/python/pants/engine:rules',
+    'src/python/pants/engine:selectors',
+    'src/python/pants/engine/legacy:structs',
+    'src/python/pants/rules/core',
+    'src/python/pants/source',
+    'src/python/pants/testutil:test_base',
+    'src/python/pants/testutil/subsystem',
+  ],
+  tags = {'integration'},
+  timeout = 90,
+)

src/python/pants/backend/python/lint/black/register.py

@@ -0,0 +1,13 @@
+# Copyright 2019 Pants project contributors (see CONTRIBUTORS.md).
+# Licensed under the Apache License, Version 2.0 (see LICENSE).
+
+
+from pants.backend.python.lint.black import rules as black_rules
+from pants.backend.python.targets import formattable_python_target
+
+
+def rules():
+  return (
+    *black_rules.rules(),
+    *formattable_python_target.rules(),
+  )

src/python/pants/backend/python/rules/black.py → src/python/pants/backend/python/lint/black/rules.py

@@ -6,13 +6,13 @@
 from pathlib import Path
 from typing import Optional, Tuple
 
+from pants.backend.python.lint.black.subsystem import Black
 from pants.backend.python.rules.pex import (
   CreatePex,
   Pex,
   PexInterpreterConstraints,
   PexRequirements,
 )
-from pants.backend.python.subsystems.black import Black
 from pants.backend.python.subsystems.python_setup import PythonSetup
 from pants.backend.python.subsystems.subprocess_environment import SubprocessEncodingEnvironment
 from pants.backend.python.targets.formattable_python_target import FormattablePythonTarget

src/python/pants/backend/python/rules/black_integration_test.py → src/python/pants/backend/python/lint/black/rules_integration_test.py

@@ -3,10 +3,10 @@
 
 from typing import List, Optional, Tuple
 
-from pants.backend.python.rules.black import BlackSetup, fmt, lint, setup_black
+from pants.backend.python.lint.black.rules import BlackSetup, fmt, lint, setup_black
+from pants.backend.python.lint.black.subsystem import Black
 from pants.backend.python.rules.download_pex_bin import download_pex_bin
 from pants.backend.python.rules.pex import CreatePex, create_pex
-from pants.backend.python.subsystems.black import Black
 from pants.backend.python.subsystems.python_native_code import (
   PythonNativeCode,
   create_pex_native_build_environment,

src/python/pants/backend/python/register.py

@@ -6,15 +6,13 @@
 from pants.backend.python.python_requirement import PythonRequirement
 from pants.backend.python.python_requirements import PythonRequirements
 from pants.backend.python.rules import (
-  black,
   download_pex_bin,
   inject_init,
   pex,
   python_create_binary,
   python_test_runner,
 )
 from pants.backend.python.subsystems import python_native_code, subprocess_environment
-from pants.backend.python.targets import formattable_python_target
 from pants.backend.python.targets.python_app import PythonApp
 from pants.backend.python.targets.python_binary import PythonBinary
 from pants.backend.python.targets.python_distribution import PythonDistribution
@@ -94,9 +92,7 @@ def register_goals():
 
 def rules():
   return (
-    *black.rules(),
     *download_pex_bin.rules(),
-    *formattable_python_target.rules(),
     *inject_init.rules(),
     *pex.rules(),
     *python_test_runner.rules(),

src/python/pants/backend/python/rules/BUILD

@@ -43,20 +43,9 @@ python_tests(
   name='integration',
   sources=globs('*_integration_test.py'),
   dependencies=[
-    ':rules',
-    'src/python/pants/backend/python/subsystems',
-    'src/python/pants/backend/python/targets',
-    'src/python/pants/engine:fs',
-    'src/python/pants/engine:rules',
-    'src/python/pants/engine:selectors',
-    'src/python/pants/engine/legacy:structs',
-    'src/python/pants/rules/core',
-    'src/python/pants/source',
-    'src/python/pants/testutil:test_base',
-    'src/python/pants/testutil/subsystem',
     'src/python/pants/testutil:int-test',
     'testprojects/tests/python/pants:dummies_directory',
   ],
   tags = {'integration'},
-  timeout = 160,
+  timeout = 90,
 )