SQL Developer 4.0: 'Open Declaration' bugs

Question

There are several issues I have with this function:
1) Sometimes, when used, it would just "hang" the UI, loading the CPU for 50% for a few seconds.
2) It doesn't seem to work for functions/procedures outside packages, you have to use 'Popup describe' instead. Is that intended?
3) I don't know if it's actually related to 'Open Declaration', but Logging Page sometimes throws a pair oracle.dbtools.parser.plsql.DictionaryQuery errors, supposedly around the same time hangs occur I may be wrong on this one, but still thought it's worth reporting:
Error 1:
select null name, -1 LINE, -1 COL, null USAGE,
case when obj.object_type like 'JAVA%' then 'JAVA' else obj.object_type end TYPE,
OWNER, case when obj.object_type like 'JAVA%' then 'JAVA' else obj.object_type end OBJECT_TYPE,
obj.OBJECT_NAME
from sys.dba_objects obj where rownum <= 10 and obj.object_type != 'TABLE PARTITION' and obj.object_type != 'TABLE SUBPARTITION' and obj.object_type != 'JAVA CLASS' and object_name like :object_name and object_type = :object_type
union all
select null name, -1 LINE, -1 COL, null USAGE,
case when obj.object_type like 'JAVA%' then 'JAVA' else obj.object_type end TYPE,
OWNER, case when obj.object_type like 'JAVA%' then 'JAVA' else obj.object_type end OBJECT_TYPE,
obj.OBJECT_NAME
from sys.dba_objects obj where rownum <= 10 and obj.object_type != 'TABLE PARTITION' and obj.object_type != 'TABLE SUBPARTITION' and obj.object_type != 'JAVA CLASS' and object_name like :object_name and object_type = :object_type
union all
select * from (select text name, LINE, instr(upper(text),upper(:text)) COL, null USAGE, TYPE, OWNER, type OBJECT_TYPE, name OBJECT_NAME
from sys.all_source where rownum <= 10
and upper(text) like upper(:text1) and name not like 'BIN$%'
and (instr(text,'--')<=0 or instr(text,'--')>instr(upper(text),upper(:text2)))
and (instr(text,'/*')<=0 or instr(text,'/*')>instr(upper(text),upper(:text3)))
and type like 'PACKAGE%' and name = :name
) where col = 1 or substr(name/*text*/,col-1,1)=' '
order by type, line and owner = :owner
Error 2:
ORA-00907: missing right parenthesis
The 'and owner = :owner' part is obviously misplaced, causing the error.
P.S. A bit off-topic: SQLDev gives me quite a lot of various warnings both on logging page and in console. They don't seem to break anything, but should I report them anyway? And should I create a separate thread for each group of these, if I do?

Answer 1

Okay, I've done some testing. It's far from exhaustive, but shows that 'Open Declaration' works differently in worksheet and package pl/sql editor, and that it depends on the case of the procedure/function that is inspected!
I also found out the cause of ORA-00907 message.
The cause of hangs also became somewhat possible to determine.
Sorry I couldn't test it more, but I already wasted about 2 hours on it, because I did it on our test (much slower) database, and each hang lasted about half a minute. I also didn't test inter-package 'Open Declaration' behavior, because I still have work to do. Hopefully what I found will be enough.
Also, another note is that "hangs" didn't burn the CPU while I tested it, unlike on production database.
We don't have HR schema anymore, so I unlocked SCOTT/TIGER forgotten by everyone, which had no functions/packages/whatsoever, only 4 tables.
All tests were done under 'SCOTT' user. Here's the test suite:
Creating the necessary function, procedure and package:
create or replace function z_test_opendecl_f return number as
begin
  return 1;
end z_test_opendecl_f;
create or replace procedure z_test_opendecl_proc as
begin
  null;
end z_test_opendecl_proc;
create or replace package z_test_opendecl_pack is
  function call_z_func return number;
  procedure call_z_proc;
end z_test_opendecl_pack;
create or replace package body z_test_opendecl_pack is
  procedure call_z_proc is
  begin
  --call lowercase external proc without schema
  --popup describe works
  --open declaration throws "PL/SQL unit Z_TEST_OPENDECL_PROC does not exist" message box
  --AND (nailed it!) writes ORA-00907 message I mentioned earlier in point (3) to logging page.
  Z_TEST_OPENDECL_PROC;
  --call lowercase external proc without schema
  --same behavior as above
  z_test_opendecl_proc;
  --call mixed case external proc without schema
  --same behavior as above
  Z_Test_Opendecl_Proc;
  --call lowercase external proc with schema
  --popup describe works
  --open declaration hangs, then opens procedure
  scott.z_test_opendecl_proc;
--call mixed case external proc with schema
  --popup describe works
  --open declaration hangs, then gives messagebox
  scott.Z_Test_Opendecl_Proc;
  end call_z_proc;
  function call_z_func return number is
  vRet number;
  begin
  --Same behavior as with procedures above
  vRet := z_test_opendecl_f;
  vRet := scott.z_test_opendecl_f;
  --Calling the procedure inside the package
  --without schema, uppercase
  --popup describe opens spec
  --open declaration hangs, then opens spec
  CALL_Z_PROC;
  --without schema, uppercase
  --popup describe opens spec
  --open declaration hangs, then opens spec
  Z_TEST_OPENDECL_PACK.CALL_Z_PROC;
  --with schema, uppercase
  --popup describe opens 'SCOTT' user popup
  --open declaration hangs, then opens spec
  SCOTT.Z_TEST_OPENDECL_PACK.CALL_Z_PROC;
  --Inline SQL, 'Open Declaration' behavior:
  select Z_TEST_OPENDECL_F --gives a messagebox, whatever the case
  into vRet
  from dual d
  where z_test_opendecl_f = 1 -- messagebox
  or scott.z_test_opendecl_f = 1 --opens declaration
  or CALL_Z_FUNC = 1 -- scrolls to function declaration
  or Z_TEST_OPENDECL_PACK.CALL_Z_FUNC = 1 --hangs, opens declaration
  or SCOTT.Z_TEST_OPENDECL_PACK.CALL_Z_FUNC = 1; --does NOTHING
  end call_z_func;
end z_test_opendecl_pack;
(Comments inside package body apply to Package Body Editor).
Here are the tests for worksheet:
--Worksheet tests
declare
  vRet number;
begin
  --NO SCHEMA SPECIFIED
  --call the procedure
  --both popup describe and open declaration open the procedure page
  Z_TEST_OPENDECL_PROC;
  --call the procedure - lowercase
  --both popup describe and open declaration open the procedure page
  z_test_opendecl_proc;
  --call the procedure - mixed case
  --popup describe opens the page
  --open declaration shows "PL/SQL unit Z_Test_Opendecl_Proc does not exist" messagebox
  Z_Test_Opendecl_Proc;
  --call the function
  --both popup describe and open declaration open the function page
  vRet := Z_TEST_OPENDECL_F;
  --call the function - lowercase
  --both popup describe and open declaration open the function page
  vRet := z_test_opendecl_f;
  --call the function - mixed case
  --popup describe opens the page
  --open declaration shows "PL/SQL unit Z_TEST_opendecl_f does not exist" messagebox
  vRet := Z_TEST_opendecl_f;
  -- call the package procedure
  -- popup describe opens package spec
  -- open declaration hangs, then opens package spec
  Z_TEST_OPENDECL_PACK.CALL_Z_PROC;
  -- call the package function
  -- popup describe opens package spec
  -- open declaration hangs, then opens package spec
  vRet := Z_TEST_OPENDECL_PACK.CALL_Z_FUNC;
  -- call the package function - mixed case
  -- popup describe opens package spec
  -- open declaration hangs, then shows "PL/SQL unit CALL_z_func does not exist" messagebox
  vRet := Z_TEST_OPENDECL_PACK.CALL_z_func;
  --inline SQL
  --Shows the same behavior
  select Z_TEST_OPENDECL_F --works
  into vRet
  from dual
  where Z_TEST_OPENDECL_F = 1 -- works
  or Z_TEST_OPENDECL_PACK.CALL_Z_FUNC = 1 -- hangs, but works
  or Z_TEST_opendecl_f = 1; -- messagebox
  --WITH SCHEMA SPECIFIED
  --Usual calls mostly exhibit the same behavior, except all of them hang on "Open Declaration" now
  -- call the package function
  -- popup describe opens 'SCOTT' user popup (!?)
  -- open declaration hangs, then opens package spec
  vRet := SCOTT.Z_TEST_OPENDECL_PACK.CALL_Z_FUNC;
  --inline SQL
  --Shows the same behavior
  select SCOTT.Z_TEST_OPENDECL_F --works
  into vRet
  from dual
  where SCOTT.Z_TEST_OPENDECL_F = 1 -- works
  or SCOTT.Z_TEST_OPENDECL_PACK.CALL_Z_FUNC = 1 -- hangs, but works
  or SCOTT.Z_TEST_opendecl_f = 1; -- messagebox
end;
There was also an error on production DB I wasn't able to reproduce while testing:
while editing package body, calling 'Open Declaration' on function name inside inline SQL did nothing - neither the message box appeared nor declaration was opened, it also doesn't hang.
I can't disclose the names, but it looks like this:
select myFunction(t.id,vLocalVar) into vLocalVar2 from tablename t;
We have a lot of objects on production, maybe it times out or something, I don't know. Autocomplete also doesn't work unless I call it explicitly with ctrl+space.
An assumption regarding the hangs: we have a ton of public synonyms and a lot of java objects; the hangs are probably related to poor java object querying performance discussed in neighboring topic.