Added ``--local-snapshots-ok`` flag, to allow building eggs from

projects installed using ``setup.py develop``.  (backport from trunk)

--HG--
branch : setuptools-0.6
extra : convert_revision : svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/sandbox/branches/setuptools-0.6%4053877

3 files changed, 32 insertions, 32 deletions

diff --git a/setuptools/command/develop.py b/setuptools/command/develop.py
index 4e19e07a..dfc41764 100755
--- a/setuptools/command/develop.py
+++ b/setuptools/command/develop.py
@@ -31,7 +31,7 @@ class develop(easy_install):
         self.uninstall = None
         self.egg_path = None
         easy_install.initialize_options(self)
-
+        self.setup_path = None
 
 
 
@@ -61,6 +61,7 @@ class develop(easy_install):
                 " directory to "+target
         )
 
+        
         # Make a distribution for the package's source
         self.dist = Distribution(
             target,
@@ -68,16 +69,15 @@ class develop(easy_install):
             project_name = ei.egg_name
         )
 
-
-
-
-
-
-
-
-
-
-
+        p = self.egg_base.replace(os.sep,'/')
+        if p!= os.curdir:
+            p = '../' * (p.count('/')+1)
+        self.setup_path = p
+        p = normalize_path(os.path.join(self.install_dir, self.egg_path, p))
+        if  p != normalize_path(os.curdir):
+            raise DistutilsOptionError(
+                "Can't get a consistent path to setup script from"
+                " installation directory", p, normalize_path(os.curdir))
 
 
     def install_for_development(self):
@@ -95,7 +95,7 @@ class develop(easy_install):
         log.info("Creating %s (link to %s)", self.egg_link, self.egg_base)
         if not self.dry_run:
             f = open(self.egg_link,"w")
-            f.write(self.egg_path)
+            f.write(self.egg_path + "\n" + self.setup_path)
             f.close()
         # postprocess the installed distro, fixing up .pth, installing scripts,
         # and handling requirements
@@ -106,7 +106,7 @@ class develop(easy_install):
         if os.path.exists(self.egg_link):
             log.info("Removing %s (link to %s)", self.egg_link, self.egg_base)
             contents = [line.rstrip() for line in file(self.egg_link)]
-            if contents != [self.egg_path]:
+            if contents not in ([self.egg_path], [self.egg_path, self.setup_path]):
                 log.warn("Link points to %s: uninstall aborted", contents)
                 return
             if not self.dry_run:
diff --git a/setuptools/command/easy_install.py b/setuptools/command/easy_install.py
index b8242520..c21307e3 100755
--- a/setuptools/command/easy_install.py
+++ b/setuptools/command/easy_install.py
@@ -70,18 +70,18 @@ class easy_install(Command):
         ('editable', 'e', "Install specified packages in editable form"),
         ('no-deps', 'N', "don't install dependencies"),
         ('allow-hosts=', 'H', "pattern(s) that hostnames must match"),
+        ('local-snapshots-ok', 'l', "allow building eggs from local checkouts"),
     ]
     boolean_options = [
         'zip-ok', 'multi-version', 'exclude-scripts', 'upgrade', 'always-copy',
         'delete-conflicting', 'ignore-conflicts-at-my-risk', 'editable',
-        'no-deps',
+        'no-deps', 'local-snapshots-ok',
     ]
     negative_opt = {'always-unzip': 'zip-ok'}
     create_index = PackageIndex
 
-
     def initialize_options(self):
-        self.zip_ok = None
+        self.zip_ok = self.local_snapshots_ok = None
         self.install_dir = self.script_dir = self.exclude_scripts = None
         self.index_url = None
         self.find_links = None
@@ -177,7 +177,8 @@ class easy_install(Command):
                 self.find_links = self.find_links.split()
         else:
             self.find_links = []
-
+        if self.local_snapshots_ok:
+            self.package_index.scan_egg_links(self.shadow_path+sys.path)
         self.package_index.add_find_links(self.find_links)
         self.set_undefined_options('install_lib', ('optimize','optimize'))
         if not isinstance(self.optimize,int):
@@ -202,7 +203,6 @@ class easy_install(Command):
 
         self.outputs = []
 
-
     def run(self):
         if self.verbose<>self.distribution.verbose:
             log.set_verbosity(self.verbose)
diff --git a/setuptools/package_index.py b/setuptools/package_index.py
index d3f3f561..e4d7e6b9 100755
--- a/setuptools/package_index.py
+++ b/setuptools/package_index.py
@@ -228,20 +228,20 @@ class PackageIndex(Environment):
         else:
             self.warn(msg, url)
 
-
-
-
-
-
-
-
-
-
-
-
-
-
-
+    def scan_egg_links(self, search_path):
+        for item in search_path:
+            if os.path.isdir(item):
+                for entry in os.listdir(item):
+                    if entry.endswith('.egg-link'):
+                        self.scan_egg_link(item, entry)
+
+    def scan_egg_link(self, path, entry):
+        lines = filter(None, map(str.strip, file(os.path.join(path, entry))))
+        if len(lines)==2:
+            for dist in find_distributions(os.path.join(path, lines[0])):
+                dist.location = os.path.join(path, *lines)
+                dist.precedence = SOURCE_DIST
+                self.add(dist)
 
 
     def process_index(self,url,page):