Delete unused old python pipeline classes.

3rdparty/python/BUILD

@@ -12,7 +12,6 @@ python_requirement_library(
     # TODO: this library is not currently linked from pypi, so we override the repository
     # to fetch it from antlr.org instead. If at any point it reappears on pypi, the
     # repository arg can be removed.
-    #   see also: tests/python/pants_test/backend/python/test_python_chroot.py
     python_requirement('antlr_python_runtime==3.1.3',
                        repository='http://www.antlr3.org/download/Python/')
   ]

src/python/pants/backend/codegen/thrift/python/BUILD

@@ -4,12 +4,6 @@
 python_library(
   dependencies = [
     'src/python/pants/backend/codegen/thrift/lib',
-    # Note that this is part of a gnarly dependency chain:
-    #  backend/python:thrift_builder ->
-    #  backend/codegen/thrift/python ->
-    #  backend/python/targets:python
-    # This isn't circular, but it's still bad that it crosses between backends and back again.
-    # TODO: Clean this up. thrift_builder should almost certainly be in the codegen backend.
     'src/python/pants/backend/python/targets:python',
     'src/python/pants/goal:task_registrar',
   ],

src/python/pants/backend/python/BUILD

@@ -21,15 +21,12 @@ python_library(
   name = 'all_utils',
   sources = globs('*.py', exclude=[['__init__.py', 'register.py']]),
   dependencies = [
-    ':antlr_builder',
     ':code_generator',
     ':interpreter_cache',
     ':python_artifact',
-    ':python_chroot',
     ':python_requirement',
     ':python_requirements',
     ':sdist_builder',
-    ':thrift_builder',
   ]
 )
 
@@ -41,18 +38,6 @@ page(
   ]
 )
 
-python_library(
-  name = 'antlr_builder',
-  sources = ['antlr_builder.py'],
-  dependencies = [
-    ':code_generator',
-    'src/python/pants/base:build_environment',
-    'src/python/pants/base:exceptions',
-    'src/python/pants/ivy',
-    'src/python/pants/util:dirutil',
-  ]
-)
-
 python_library(
   name = 'code_generator',
   sources = ['code_generator.py'],
@@ -96,25 +81,6 @@ python_library(
   ],
 )
 
-python_library(
-  name = 'python_chroot',
-  sources = ['python_chroot.py'],
-  dependencies = [
-    '3rdparty/python/twitter/commons:twitter.common.collections',
-    '3rdparty/python:pex',
-    ':antlr_builder',
-    ':python_requirement',
-    ':thrift_builder',
-    'src/python/pants/backend/codegen/antlr/python',
-    'src/python/pants/backend/codegen/thrift/python',
-    'src/python/pants/backend/python/targets:python',
-    'src/python/pants/base:build_environment',
-    'src/python/pants/build_graph',
-    'src/python/pants/invalidation',
-    'src/python/pants/util:dirutil'
-  ],
-)
-
 python_library(
   name = 'python_requirement',
   sources = ['python_requirement.py'],
@@ -132,23 +98,3 @@ python_library(
     '3rdparty/python:pex',
   ]
 )
-
-python_library(
-  name = 'thrift_builder',
-  sources = ['thrift_builder.py'],
-  dependencies = [
-    '3rdparty/python/twitter/commons:twitter.common.collections',
-    ':code_generator',
-      # Note that this is part of a gnarly dependency chain:
-      #  backend/python:thrift_builder ->
-      #  src/python/pants/backend/codegen/thrift/python ->
-      #  backend/python/targets:python
-      # This isn't circular, but it's still bad that it crosses between backends and back again.
-      # TODO: Clean this up. thrift_builder should almost certainly be in the codegen backend.
-    'src/python/pants/backend/codegen/thrift/python',
-    'src/python/pants/base:build_environment',
-    'src/python/pants/util:dirutil',
-    'src/python/pants/util:memo',
-    'src/python/pants/util:process_handler',
-  ]
-)