Merged Evans product path fix from 2.2 branch

lib/python/App/FindHomes.py

@@ -85,41 +85,60 @@
 
 """Commonly used utility functions."""
 
-__version__='$Revision: 1.3 $'[11:-2]
+__version__='$Revision: 1.4 $'[11:-2]
 
 import os, sys, Products, string
 from Common import package_home
+path_join = os.path.join
+path_split = os.path.split
 
 try: home=os.environ['SOFTWARE_HOME']
 except:
     home=package_home(Products.__dict__)
     if not os.path.isabs(home):
-        home=os.path.join(os.getcwd(), home)
+        home=path_join(os.getcwd(), home)
         
-    home,e=os.path.split(home)
-    if os.path.split(home)[1]=='.': home=os.path.split(home)[0]
-    if os.path.split(home)[1]=='..':
-        home=os.path.split(os.path.split(home)[0])[0]
+    home,e=path_split(home)
+    if path_split(home)[1]=='.': home=path_split(home)[0]
+    if path_split(home)[1]=='..':
+        home=path_split(path_split(home)[0])[0]
 
 sys.modules['__builtin__'].SOFTWARE_HOME=SOFTWARE_HOME=home
 
 try: chome=os.environ['INSTANCE_HOME']
 except:
     chome=home
-    d,e=os.path.split(chome)
+    d,e=path_split(chome)
     if e=='python':
-        d,e=os.path.split(d)
+        d,e=path_split(d)
         if e=='lib': chome=d or os.getcwd()
     
 sys.modules['__builtin__'].INSTANCE_HOME=INSTANCE_HOME=chome
 
 # If there is a Products package in INSTANCE_HOME, add it to the
 # Products package path
-ip=os.path.join(INSTANCE_HOME, 'Products')
-
-if os.path.isdir(ip) and ip not in Products.__path__:
+ip=path_join(INSTANCE_HOME, 'Products')
+ippart = 0
+ppath = Products.__path__
+if os.path.isdir(ip) and ip not in ppath:
     disallow=string.lower(os.environ.get('DISALLOW_LOCAL_PRODUCTS',''))
     if disallow in ('no', 'off', '0', ''):
-        Products.__path__.insert(0, ip)
-    
-    
+        ppath.insert(0, ip)
+        ippart = 1
+        
+ppathpat = os.environ.get('PRODUCTS_PATH', None)
+if ppathpat is not None:
+    psep = os.pathsep
+    if string.find(ppathpat, '%(') >= 0:
+        newppath = string.split(ppathpat % {
+            'PRODUCTS_PATH': string.join(ppath, psep),
+            'SOFTWARE_PRODUCTS': string.join(ppath[ippart:], psep),
+            'INSTANCE_PRODUCTS': ip,
+            }, psep)
+    else:
+        newppath = string.split(ppathpat, psep)
+    del ppath[:]
+    for p in filter(None, newppath):
+        p = os.path.abspath(p)
+        if os.path.isdir(p) and p not in ppath:
+            ppath.append(p)