Fix #91: pgpassfile is not defined at w32 because APPDATA is not defined

Author: phdru

postgresql/clientparameters.py

@@ -147,6 +147,8 @@ def defaults(environ = os.environ):
 		if appdata:
 			pgdata = os.path.join(appdata, pg_appdata_directory)
 			pgpassfile = os.path.join(pgdata, pg_appdata_passfile)
+		else:
+			pgpassfile = None
 	else:
 		pgpassfile = os.path.join(userdir, pg_home_passfile)
 
@@ -157,7 +159,7 @@ def defaults(environ = os.environ):
 		('sslrootcrlfile', os.path.join(pgdata, 'root.crl')),
 		('pgpassfile', pgpassfile),
 	):
-		if os.path.exists(v):
+		if v and os.path.exists(v):
 			yield (k,), v
 
 def envvars(environ = os.environ, modifier = 'PG'.__add__):