Fix several issues in cmd_ac_complete_filepath:
* Prevent a segfault when input is empty.
* Fix a double free where acstring was managed by both auto_gchar and GArray.
* Fix a memory leak when reassigning inpcp during quote stripping.
* Restore the ability to cycle through files on repeated TAB presses by
caching the last input and skipping updates if the input is already a
known completion.
* Preserve user input style (e.g. ~, ./) in autocompletion strings to
ensure matches are correctly displayed and filtered.
Bug got introduced when "cleaning" code with new compiler flags and
sanitizers: aec8e48268.
Add unit tests so this doesn't happen again.
Before that commit we didn't use the static variable but used
autocomplete_update instead. Now we avoid redundat updates and preserve
the state across tab presses. We should look at this again later.
Fix https://github.com/profanity-im/profanity/issues/2098
Use a behavior-driven naming convention for unit tests.
Functions are now named using the pattern: [unit]__[verb]__[scenario]
The __ works as a semantic separator.
Examples:
* jid_create__returns__null_from_null()
* cmd_connect__shows__usage_when_no_server_value
Benefits:
* Easy to find all tests associated with a specific function using the
mandatory prefix.
* Test output in CI now explicitly describes the unit, the expected
outcome, and the scenario being tested.
Also disabled keyhandlers tests due to missing code in src/ui.
For example cmd_account() is located in src/command/cmd_funcs.c.
The unit test was located in tests/unittests/test_cmd_account.c.
Let's move it to a subdirectory like tests/unittests/command/test_cmd_account.c
to correpsond to the same structure.
