ruby - Rake dependency not executing but invoke works -

i've been trying run rake db:test:clone_structure, keeps failing rebuild database. looked @ task itself:

task :clone_structure => [ "db:structure:dump", "db:test:load_structure" ] 

when run trace, i've noticed db:test:load_structure isn't getting executed:

$ rake db:test:clone_structure --trace ** invoke db:test:clone_structure (first_time) ** invoke db:structure:dump (first_time) ** invoke environment (first_time) ** execute environment ** execute db:structure:dump ** invoke db:test:purge (first_time) ** invoke environment  ** execute db:test:purge ** execute db:test:clone_structure 

now, when change clone_structure task invoke load_structure...

task :clone_structure => [ "db:structure:dump", "db:test:load_structure" ]      db_namespace["test:load_structure"].invoke end 

...everything works!

$ rake db:test:prepare --trace  ** invoke db:test:clone_structure (first_time) ** invoke db:structure:dump (first_time) ** invoke environment (first_time) ** execute environment ** execute db:structure:dump ** invoke db:test:purge (first_time) ** invoke environment  ** execute db:test:purge ** execute db:test:clone_structure ** invoke db:test:load_structure (first_time) ** invoke db:test:purge  ** execute db:test:load_structure ** invoke db:structure:load (first_time) ** invoke environment  ** invoke db:load_config (first_time) ** execute db:load_config ** execute db:structure:load 

what possibly causing behavior? i'm using rails 3.2.14 , rake 10.1.0.

updated: upgraded rails 3.2.13 3.2.11 , it's still problem.

updated second: upgraded rails 3.2.14 , rake 10.1.0 , it's still problem

i there. far know rake convention be...

task :clone_structure => [ "db:structure:dump", "db:test:load_structure" ]      rake::task["clone_structure"].invoke end 

otherwise, prefer...

task :clone_structure      rake::task["db:structure:dump"].invoke   rake::task["db:test:load_structure"].invoke end