[feat] zc.recipe.egg: Support on the fly patches.

- Support on the fly patches in zc.recipe.egg by ``EGGNAME-patches``,
  ``EGGNAME-patch-options``, ``EGGNAME-patch-binary`` (or
  ``patch-binary``) and ``EGGNAME-patch-revision`` options.

- Support on the fly patches in zc.recipe.egg:custom by ``patches``,
  ``patch-options``, ``patch-binary`` and ``patch-revision`` options.
  (options ``EGGNAME-*`` are also supported as well).

src/zc/buildout/easy_install.py

@@ -81,6 +81,9 @@ is_source_encoding_line = re.compile(r'coding[:=]\s*([-\w.]+)').search
 is_win32 = sys.platform == 'win32'
 is_jython = sys.platform.startswith('java')
 
+PATCH_MARKER = 'SlapOSPatched'
+orig_versions_re = re.compile(r'[+\-]%s\d+' % PATCH_MARKER)
+
 if is_jython:
     import java.lang.System
     jython_os_name = (java.lang.System.getProperties()['os.name']).lower()
@@ -464,6 +467,11 @@ class Installer(object):
             zc.buildout.rmtree.rmtree(tmp)
 
     def _obtain(self, requirement, source=None):
+        # get the non-patched version
+        req = str(requirement)
+        if PATCH_MARKER in req:
+            requirement = pkg_resources.Requirement.parse(re.sub(orig_versions_re, '', req))
+
         # initialize out index for this project:
         index = self._index
 
@@ -676,7 +684,7 @@ class Installer(object):
 
         return requirement
 
-    def install(self, specs, working_set=None):
+    def install(self, specs, working_set=None, patch_dict=None):
 
         logger.debug('Installing %s.', repr(specs)[1:-1])
         __doing__ = _doing_list, self._requirements_and_constraints
@@ -700,6 +708,9 @@ class Installer(object):
             ws = working_set
 
         for requirement in requirements:
+            if patch_dict and requirement.project_name in patch_dict:
+                self._env.scan(
+                    self.build(str(requirement), {}, patch_dict=patch_dict))
             for dist in self._get_dist(requirement, ws):
                 self._maybe_add_setuptools(ws, dist)
 
@@ -798,7 +809,7 @@ class Installer(object):
             processed[req] = True
         return ws
 
-    def build(self, spec, build_ext):
+    def build(self, spec, build_ext, patch_dict=None):
 
         requirement = self._constrain(pkg_resources.Requirement.parse(spec))
 
@@ -849,12 +860,31 @@ class Installer(object):
                             )
                     base = os.path.dirname(setups[0])
 
+                setup_cfg_dict = {'build_ext':build_ext}
+                patch_dict = (patch_dict or {}).get(re.sub('[<>=].*', '', spec))
+                if patch_dict:
+                    setup_cfg_dict.update(
+                      {'egg_info':{'tag_build':'+%s%03d' % (PATCH_MARKER,
+                                                            patch_dict['patch_revision'])}})
+                    for i, patch in enumerate(patch_dict['patches']):
+                        url, md5sum = (patch.strip().split('#', 1) + [''])[:2]
+                        download = zc.buildout.download.Download()
+                        path, is_temp = download(url, md5sum=md5sum or None,
+                                                 path=os.path.join(tmp, 'patch.%s' % i))
+                        args = [patch_dict['patch_binary']] + patch_dict['patch_options']
+                        kwargs = {'cwd':base,
+                                  'stdin':open(path)}
+                        popen = subprocess.Popen(args, **kwargs)
+                        popen.communicate()
+                        if popen.returncode != 0:
+                            raise subprocess.CalledProcessError(
+                                popen.returncode, ' '.join(args))
                 setup_cfg = os.path.join(base, 'setup.cfg')
                 if not os.path.exists(setup_cfg):
                     f = open(setup_cfg, 'w')
                     f.close()
                 setuptools.command.setopt.edit_config(
-                    setup_cfg, dict(build_ext=build_ext))
+                    setup_cfg, setup_cfg_dict)
 
                 dists = self._call_pip_wheel(base, self._dest, dist)
 
@@ -974,6 +1004,7 @@ def install(specs, dest,
             allowed_eggs_from_site_packages=None,
             check_picked=True,
             allow_unknown_extras=False,
+            patch_dict=None,
             ):
     assert executable == sys.executable, (executable, sys.executable)
     assert include_site_packages is None
@@ -985,18 +1016,19 @@ def install(specs, dest,
                           allow_hosts=allow_hosts,
                           check_picked=check_picked,
                           allow_unknown_extras=allow_unknown_extras)
-    return installer.install(specs, working_set)
+    return installer.install(specs, working_set, patch_dict=patch_dict)
 
 
 def build(spec, dest, build_ext,
           links=(), index=None,
           executable=sys.executable,
-          path=None, newest=True, versions=None, allow_hosts=('*',)):
+          path=None, newest=True, versions=None, allow_hosts=('*',),
+          patch_dict=None):
     assert executable == sys.executable, (executable, sys.executable)
     installer = Installer(dest, links, index, executable,
                           True, path, newest,
                           versions, allow_hosts=allow_hosts)
-    return installer.build(spec, build_ext)
+    return installer.build(spec, build_ext, patch_dict=patch_dict)
 
 
 def _rm(*paths):

zc.recipe.egg_/src/zc/recipe/egg/README.rst

@@ -9,6 +9,19 @@ eggs
     requirement strings.  Each string must be given on a separate
     line.
 
+patch-binary
+   The path to the patch executable.
+
+EGGNAME-patches
+   A new-line separated list of patchs to apply when building.
+
+EGGNAME-patch-options
+   Options to give to the patch program when applying patches.
+
+EGGNAME-patch-revision
+   An integer to specify the revision (default is the number of
+   patches).
+
 find-links
    A list of URLs, files, or directories to search for distributions.
 

zc.recipe.egg_/src/zc/recipe/egg/custom.py

@@ -15,6 +15,7 @@
 """
 import logging
 import os
+import re
 import sys
 
 import zc.buildout.easy_install
@@ -70,6 +71,30 @@ class Base:
                 except KeyError:
                     pass
 
+    def _get_patch_dict(self, options, distribution):
+        patch_dict = {}
+        global_patch_binary = options.get('patch-binary', 'patch')
+        def get_option(egg, key, default):
+            return options.get('%s-%s' % (egg, key),
+                               options.get(key, default))
+        egg = re.sub('[<>=].*', '', distribution)
+        patches = filter(lambda x:x,
+                         map(lambda x:x.strip(),
+                             get_option(egg, 'patches', '').splitlines()))
+        patches = list(patches)
+        if not patches:
+            return patch_dict
+        patch_options = get_option(egg, 'patch-options', '-p0').split()
+        patch_binary = get_option(egg, 'patch-binary', global_patch_binary)
+        patch_revision = int(get_option(egg, 'patch-revision', len(patches)))
+        patch_dict[egg] = {
+          'patches':patches,
+          'patch_options':patch_options,
+          'patch_binary':patch_binary,
+          'patch_revision':patch_revision,
+        }
+        return patch_dict
+
 
 class Custom(Base):
 
@@ -127,10 +152,11 @@ class Custom(Base):
             extra_path = os.pathsep.join(ws.entries)
             self.environment['PYTHONEXTRAPATH'] = os.environ['PYTHONEXTRAPATH'] = extra_path
 
+        patch_dict = self._get_patch_dict(options, distribution)
         return zc.buildout.easy_install.build(
             distribution, options['_d'], self.build_ext,
             self.links, self.index, sys.executable,
-            [options['_e']], newest=self.newest,
+            [options['_e']], newest=self.newest, patch_dict=patch_dict,
             )
 
 

zc.recipe.egg_/src/zc/recipe/egg/custom.rst

@@ -24,6 +24,19 @@ setup-eggs
    A new-line separated list of eggs that need to be installed
    beforehand. It is useful to meet the `setup_requires` requirement.
 
+patch-binary
+   The path to the patch executable.
+
+patches
+   A new-line separated list of patchs to apply when building.
+
+patch-options
+   Options to give to the patch program when applying patches.
+
+patch-revision
+   An integer to specify the revision (default is the number of
+   patches).
+
 define
    A comma-separated list of names of C preprocessor variables to
    define.

zc.recipe.egg_/src/zc/recipe/egg/egg.py

@@ -57,6 +57,34 @@ class Eggs(object):
         options['develop-eggs-directory'] = b_options['develop-eggs-directory']
         options['_d'] = options['develop-eggs-directory']  # backward compat.
 
+    def _get_patch_dict(self, options, distribution_list):
+        patch_dict = {}
+        global_patch_binary = options.get('patch-binary', 'patch')
+        def get_option(egg, key, default):
+            if len(distribution_list) == 1:
+                return options.get('%s-%s' % (egg, key),
+                                   options.get(key, default))
+            else:
+                return options.get('%s-%s' % (egg, key), default)
+        for distribution in distribution_list:
+            egg = re.sub('[<>=].*', '', distribution)
+            patches = filter(lambda x:x,
+                             map(lambda x:x.strip(),
+                                 get_option(egg, 'patches', '').splitlines()))
+            patches = list(patches)
+            if not patches:
+                continue
+            patch_options = get_option(egg, 'patch-options', '-p0').split()
+            patch_binary = get_option(egg, 'patch-binary', global_patch_binary)
+            patch_revision = int(get_option(egg, 'patch-revision', len(patches)))
+            patch_dict[egg] = {
+              'patches':patches,
+              'patch_options':patch_options,
+              'patch_binary':patch_binary,
+              'patch_revision':patch_revision,
+            }
+        return patch_dict
+
     def working_set(self, extra=()):
         """Separate method to just get the working set
 
@@ -134,6 +162,7 @@ class Eggs(object):
                     [develop_eggs_dir, eggs_dir]
                     )
             else:
+                patch_dict = self._get_patch_dict(self.options, distributions)
                 ws = zc.buildout.easy_install.install(
                     distributions, eggs_dir,
                     links=links,
@@ -141,7 +170,8 @@ class Eggs(object):
                     path=[develop_eggs_dir],
                     newest=newest,
                     allow_hosts=allow_hosts,
-                    allow_unknown_extras=allow_unknown_extras)
+                    allow_unknown_extras=allow_unknown_extras,
+                    patch_dict=patch_dict)
             ws = zc.buildout.easy_install.sort_working_set(
                 ws, buildout_dir, eggs_dir, develop_eggs_dir
                 )