Dependencies are not properly enabled by Simpletest causing errors

I've module which has dependencies to following modules in .info file:

dependencies[] = entity
dependencies[] = aat_wex_feature
dependencies[] = ctools
dependencies[] = token
dependencies[] = deeplink
dependencies[] = deeplink_workflow
dependencies[] = field_group

I assume that if I do: parent::setUp('aat_wex');, all my modules from .info files are enabled, but it doesn't happens, because I've following error during the test:

Fatal error: Call to undefined function field_group_info_groups() in aat_wex.inc on line 22

Where this function is defined in the main field_group module file.
The same with:

Fatal error: Call to undefined function ctools_include()

Only following modules are enabled:

user module installed.             
user module enabled.               
node module installed.             
node module enabled.               
filter module installed.           
filter module enabled.             
text module installed.             
text module enabled.               
field_sql_storage module installed.
field_sql_storage module enabled.  
field module installed.            
field module enabled.              
block module installed.            
block module enabled.              
color module installed.            
color module enabled.              
comment module installed.          
comment module enabled.            
contextual module installed.       
contextual module enabled.         
dashboard module installed.        
dashboard module enabled.          
help module installed.             
help module enabled.               
image module installed.            
image module enabled.              
list module installed.             
list module enabled.               
menu module installed.             
menu module enabled.               
number module installed.           
number module enabled.             
options module installed.          
options module enabled.            
path module installed.             
path module enabled.               
taxonomy module installed.         
taxonomy module enabled.           
dblog module installed.            
dblog module enabled.              
search module installed.           
search module enabled.             
shortcut module installed.         
shortcut module enabled.           
toolbar module installed.          
toolbar module enabled.            
overlay module installed.          
overlay module enabled.            
field_ui module installed.         
field_ui module enabled.           
file module installed.             
file module enabled.               
rdf module installed.              
rdf module enabled.                
date_api module installed.         
date_api module enabled.           
controls module installed.         
controls module enabled.           
deeplink module installed.         
deeplink module enabled.           
workflow module installed.         
workflow module enabled.           
deeplink_workflow module installed.
deeplink_workflow module enabled.  

before my module is enabled.
Any reason why?
Logically for me to simulate the module behavior, all dependencies should be loaded from module .info file.
If I need to enable all dependencies, where does it end? Do I have to add all contrib modules to parent::setUp() which are enabled on my site? How does it know to enable Drupal core modules?
So why some of the modules like deeplink or deeplink_workflow are enabled from .info file and the other are not?