Devel_themer is a project mainly written in PHP and JAVASCRIPT, based on the GPL-2.0 license.
Try to get devel_themer to play nice with D7
DEVEL_THEMER
This is a branch of the devel themer module, it is an attempt to get the theme_developer module working in drupal7.
I am now activly developing the devel_themer module on Drupal.org this branch may be used for some experimental features but in most cases you will want the build from there, not the code from here,
please see http://drupal.org/project/devel_themer