[nodejs-inherits/el6: 7/8] add some %triggerun hackery to fix busted upgrade paths

[T.C. Hollingsworth]

commit 73cf684ae221bba3ae4de5b6481d7f4e85bedf20
Author: T.C. Hollingsworth <tchollingsworth at gmail.com>
Date:   Fri Aug 16 14:38:54 2013 -0700

    add some %triggerun hackery to fix busted upgrade paths
    
    sometimes symlinks end up still pointing to their old (wrong)
    locations after upgrade (RHBZ#997978)

 nodejs-inherits.spec |   38 ++++++++++++++++++++++++++++++++++++--
 1 files changed, 36 insertions(+), 2 deletions(-)
---
diff --git a/nodejs-inherits.spec b/nodejs-inherits.spec
index b5dd6ae..9e3f185 100644
--- a/nodejs-inherits.spec
+++ b/nodejs-inherits.spec
@@ -2,7 +2,7 @@
 
 Name:       nodejs-inherits
 Version:    2.0.0
-Release:    3%{?dist}
+Release:    4%{?dist}
 Summary:    A tiny simple way to do classic inheritance in js
 License:    WTFPL
 Group:      Development/Libraries
@@ -40,13 +40,43 @@ ln -sf inherits at 2 %{buildroot}%{nodejs_sitelib}/inherits
 %clean
 rm -rf %{buildroot}
 
+# there have been reports that the symlinks are messed up when upgrading
+# from older versions, so let's make sure everything's copacetic
+%triggerun -- nodejs-inherits < 2.0.0-4
+ln -sf inherits at 2 %{nodejs_sitelib}/inherits
+%{__python} <<EOF
+import json, os
+
+for moddir in os.listdir('%{nodejs_sitelib}'):
+    if os.path.isdir(moddir):
+        md = json.load(open(os.path.join(moddir, 'package.json')))
+        
+        if 'dependencies' in md and 'inherits' in md['dependencies']:
+            if isinstance(md['dependencies'], dict) and '1' in md['dependencies']['inherits']:
+                src = os.path.join('%{nodejs_sitelib}', 'inherits at 1')
+            else:
+                src = os.path.join('%{nodejs_sitelib}', 'inherits at 2')
+                
+            dest = os.path.join('%{nodejs_sitelib}', moddir, 'node_modules/inherits')
+            
+            if not os.path.realpath(dest) == src:
+                try:
+                    os.unlink(dest)
+                except OSError:
+                    pass
+                    
+                try:
+                    os.symlink(src, dest)
+                except OSError, e:
+                    sys.stderr.write(e + '\n')
+EOF
+
 # rpm blows up if you try to replace a dir with a symlink or vice-versa
 %pretrans -p <lua>
 if posix.stat("%{nodejs_sitelib}/inherits", "type") == "directory" then
     os.rename('%{nodejs_sitelib}/inherits', '%{nodejs_sitelib}/inherits at 2')
 end
 
-
 %files
 %defattr(-,root,root,-)
 %{nodejs_sitelib}/inherits at 2
@@ -54,6 +84,10 @@ end
 %doc README.md LICENSE
 
 %changelog
+* Fri Aug 16 2013 T.C. Hollingsworth <tchollingsworth at gmail.com> - 2.0.0-4
+- add some post-install hackery to work around potential RPM bug resulting in
+  symlinks still pointing to their old locations on upgrade (RHBZ#997978)
+
 * Sat Jul 06 2013 T.C. Hollingsworth <tchollingsworth at gmail.com> - 2.0.0-3
 - only run the hack when we really need to